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Page 1: 1 The physical approach to the hot star description filearXiv:0802.1581v2 [astro-ph] 16 Feb 2008 1 The physical approach to the hot star description B.V.Vasiliev

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The physical approach tothe hot star description

B.V.Vasiliev

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2

Page 3: 1 The physical approach to the hot star description filearXiv:0802.1581v2 [astro-ph] 16 Feb 2008 1 The physical approach to the hot star description B.V.Vasiliev

Contents

1 Introducion 71.1 That is a base of astrophysics? . . . . . . . . . . . . . . . . . . . 71.2 The basic postulate of astrophysics . . . . . . . . . . . . . . . . . 81.3 The Galileo’s method . . . . . . . . . . . . . . . . . . . . . . . . 81.4 What does the measurement data express? . . . . . . . . . . . . 9

2 A hot dense plasma 112.1 The properties of a hot dense plasma . . . . . . . . . . . . . . . . 11

2.1.1 A hot plasma and Boltzman distribution . . . . . . . . . . 112.1.2 The correction for the Fermi-statistic . . . . . . . . . . . . 122.1.3 The correction for correlation of particles . . . . . . . . . 13

2.2 The energetically preferable state . . . . . . . . . . . . . . . . . . 142.2.1 The energetically preferable density . . . . . . . . . . . . 142.2.2 The energetically preferable temperature . . . . . . . . . . 142.2.3 Are accepted assumptions correct? . . . . . . . . . . . . . 15

3 The gravity induced electric polarization 173.1 Plasma cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173.2 The equilibrium of a nucleus . . . . . . . . . . . . . . . . . . . . 183.3 The equilibrium in electron gas subsystem . . . . . . . . . . . . . 19

4 The internal structure of a star 214.1 The plasma equilibrium in the star core . . . . . . . . . . . . . . 214.2 The main parameters of a star core . . . . . . . . . . . . . . . . . 224.3 The equilibrium inside the star atmosphere . . . . . . . . . . . . 224.4 The radial dependence of density and temperature . . . . . . . . 234.5 The mass of the star . . . . . . . . . . . . . . . . . . . . . . . . . 24

5 The main parameters of star 255.1 The energy of a star . . . . . . . . . . . . . . . . . . . . . . . . . 25

5.1.1 The kinetic energy of plasma . . . . . . . . . . . . . . . . 255.1.2 The potential energy of star plasma . . . . . . . . . . . . 26

5.2 The temperature of a star core . . . . . . . . . . . . . . . . . . . 265.2.1 The energy of the black radiation . . . . . . . . . . . . . . 26

3

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4 CONTENTS

5.2.2 The full energy of a star . . . . . . . . . . . . . . . . . . . 275.3 Main star parameters . . . . . . . . . . . . . . . . . . . . . . . . 27

5.3.1 The star mass . . . . . . . . . . . . . . . . . . . . . . . . . 275.3.2 Radii of stars . . . . . . . . . . . . . . . . . . . . . . . . . 285.3.3 The R⋆/R0 ratio and R0 . . . . . . . . . . . . . . . . . . . 325.3.4 The temperature of a star surface . . . . . . . . . . . . . . 325.3.5 The comparison with measuring data . . . . . . . . . . . 32

6 The thermodynamic relations 356.1 The thermodynamic relations . . . . . . . . . . . . . . . . . . . . 35

6.1.1 The cP /cV ratio . . . . . . . . . . . . . . . . . . . . . . . 366.1.2 The Poisson’s adiabat . . . . . . . . . . . . . . . . . . . . 37

6.2 The mass-radius ratio . . . . . . . . . . . . . . . . . . . . . . . . 376.3 The mass-temperature-luminosity relations . . . . . . . . . . . . 39

7 Magnetic fields of stars 437.1 Magnetic moments of stars . . . . . . . . . . . . . . . . . . . . . 437.2 Magnetic fields of stars . . . . . . . . . . . . . . . . . . . . . . . . 44

8 The apsidal rotation 498.1 The apsidal rotation . . . . . . . . . . . . . . . . . . . . . . . . . 498.2 The equilibrium form of the core . . . . . . . . . . . . . . . . . . 508.3 The angular velocity . . . . . . . . . . . . . . . . . . . . . . . . . 528.4 The comparison with observations . . . . . . . . . . . . . . . . . 52

9 The solar seismical oscillations 559.1 The spectrum of solar oscillations . . . . . . . . . . . . . . . . . . 559.2 The sound speed in plasma . . . . . . . . . . . . . . . . . . . . . 599.3 The basic elastic oscillation . . . . . . . . . . . . . . . . . . . . . 609.4 The low frequency oscillation . . . . . . . . . . . . . . . . . . . . 619.5 The spectrum of solar oscillations . . . . . . . . . . . . . . . . . . 62

10 Addendum I: The energy generation 63

11 Addendum II: A mechanism of stabilization for neutron-excessnuclei in plasma 6511.1 β-active isotopes of hydrogen and helium . . . . . . . . . . . . . 6511.2 The electron cloud of plasma cell . . . . . . . . . . . . . . . . . . 65

12 Addendum III: Other stars 6912.1 The atomic substance . . . . . . . . . . . . . . . . . . . . . . . . 69

12.1.1 Small bodies . . . . . . . . . . . . . . . . . . . . . . . . . 6912.1.2 Giants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

12.2 Plasmas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7012.2.1 Stars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7012.2.2 Planet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7012.2.3 The cold relativistic substance . . . . . . . . . . . . . . . 71

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CONTENTS 5

12.2.4 Quasars? . . . . . . . . . . . . . . . . . . . . . . . . . . . 7212.3 Some cosmology . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

13 The conclusion 77

Bibliography 80

14 Appendix 83

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6 CONTENTS

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Chapter 1

Introducion

1.1 That is a base of astrophysics?

Astrophysics1 is related to other physics branches by the using of standardphysical laws - laws of mechanics, statistical physics and thermodynamics, elec-trodynamics etc. However at an inevitable similarity of all physical branches,astrophysics has an unique peculiar ”architecture”. Its difference has historicalroots.

The modern physics begins its formation at last 16 c. - middle 17 c. mainlywith works of W.Gilbert and G.Galileo. They introduce into practice the maininstrument of the present exact science - the empirical testing of a scientifichypothesis. Before false scientific statements weren’t afraid of an empiricaltesting up to that time. A flight of fancy was far refined than an ordinaryand crude material world. The exact correspondence of a philosophical theoryto a check experiment was not necessary, it almost discredited the theory in anesoteric opinion. The discrepancy of a theory and observations was not confusingat that time. Now the empirical testing of all theoretical hypotheses gets agenerally accepted obligatory method of the exact science. As a result all basicstatements of physics are sure established and based on the solid foundation of. an agreement with measurement data.

Astrophysics applied standard physical laws to a description of the interiorof its subject matter - distant and mysterious stars, when there was nothingknown except that they exist. As a result, since then and up to these days,astrophysical models of a star interior are elaborated without any hope thatthey can be checked by comparison with measurement data.

At a consequence, the astrophysical community is thinking that a foundationof their science is not a measuring data, but it is a totality of astrophysical

1The modern astrophysics has a whole series of different branches. It has to be emphasizedthat almost all of them except the physics of hot stars exceed the bounds of this consideration;we shall use the term ”astrophysics” here and below in its initial meaning - as the physics ofstars or more tightly as the physics of hot stars.

7

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8 CHAPTER 1. INTRODUCION

knowledge, models of stars and their evolution, which gives a sure in an objectivecharacter of their adequacy. 2

However using the progress of a measuring technics, astronomers obtain dur-ing last decades of 20 c. the important measuring data. The existence of thesedata gives one possibility to reject the pre-Galilelian feature of astrophysicalscience and to establish its on the solid base of an agreement of the theory anddata measurement, as it accepted in all other branches of physics.

The comparison of these measuring data and appropriate theoretical modelswill be considered below in detail.

1.2 The basic postulate of astrophysics

The basic postulate of astrophysics - the Euler equation - was formulated in amathematical form by L.Euler in a middle of 18th century for the ”terrestrial”effects description. This equation determines the equilibrium condition of liquidsor gases in a gravitational field:

γg = −∇P. (1.1)

According to it the action of a gravity forth γg (γ is density of substance, g is thegravity acceleration) in equilibrium is balanced by a forth which is induced bythe pressure gradient in the substance. This postulate is surely established andexperimentally checked be ”terrestrial” physics. It is the base of an operatingof series of technical devices - balloons, bathyscaphes and other.

All modern models of stellar interior are obtained on the base of the Eulerequation. These models assume that pressure inside a star monotone increasesdepthward from the star surface. As a star interior substance can be consideredas an ideal gas which pressure is proportional to its temperature and density, allastrophysical models predict more or less monotonous increasing of temperatureand density of the star substance in the direction of the center of a star.

1.3 The Galileo’s method

The correctness of fundamental scientific postulate has to be confirmed byempirical testing. The basic postulate of astrophysics - the Euler equation(Eq.(1.1)) - was formulated long before the plasma theory has appeared, evenlong before the discovering of electrons and nuclei. Now we are sure that thestar interior must consist of electron-nuclear plasma. The Euler equation de-scribes behavior of liquids or gases - substances, consisting of neutral particles.One can ask oneself: must the electric interaction between plasmas particlesbe taken into account at a reformulation of the Euler equation, or does it givea small correction only, which can be neglected in most cases, and how is itaccepted by modern stellar theories?

2From memory, according to words of one of known European astrophysicist.

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1.4. WHAT DOES THE MEASUREMENT DATA EXPRESS? 9

To solve the problem of the correct choice of the postulate, one has theGalileo’s method. It consists of 3 steps:

(1) to postulate a hypothesis about the nature of the phenomenon, which isfree from logical contradictions;

(2) on the base of this postulate, using the standard mathematical procedures,to conclude laws of the phenomenon;

(3) by means of empirical method to ensure, that the nature obeys these laws(or not) in reality, and to confirm (or not) the basic hypothesis.

The use of this method gives a possibility to reject false postulates andtheories, provided there exist a necessary observation data, of course.

The modern theory of the star interior is based on the Euler equationEq.(1.1). Another possible approach is to take into account all interactionsacting in the considered system. Following this approach one takes into accountin the equilibrium equation the electric interactions too, because plasma par-ticles have electric charges. An energetic reason speaks that plasma in gravityfield must stay electroneutral and surplus free charges must be absent insideit.The gravity action on a neutral plasma may induce a displacements of itsparticles, i.e. its electric polarization, because electric dipole moments are low-est moments of the analysis of multipoles. If we take into account the electricpolarization plasma P, the equilibrium equation obtains the form:

γg+4π

3P∇P+∇P = 0, (1.2)

On the basis of this postulate and using standard procedures, the star interiorstructure can be considered (it is the main substance of this paper).

Below it will be shown that the electric force in a very hot dense plasma canfully compensate the gravity force and the equilibrium equation then obtainsthe form:

γg+4π

3P∇P = 0 (1.3)

and∇P = 0, (1.4)

which points to a radical distinction of this approach in comparison to thestandard scheme based on Eq.(1.1).

1.4 What does the the astronomic measurementdata express?

Are there actually astronomic measurement data, which can give possibility todistinguish ”correct” and ”incorrect” postulates? What must one do, if thedirect measurement of the star interior construction is impossible?

Are there astronomical measurement data which can clarity this problem?Yes. They are:

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10 CHAPTER 1. INTRODUCION

1. There is the only method which gives information about the distributionof the matter inside stars. It is the measurement of the periastron rotationof closed double stars. The results of these measurements give a qualitativeconfirmation that the matter of a star is more dense near to its center.

2. There is the measured distribution of star masses. Usually it does nothave any interpretation.

3. The astronomers detect the dependencies of radii of stars and their sur-face temperatures from their masses. Clear quantitative explanations of thesedependencies are unknown.

4. The existence of these dependencies leads to a mass-luminosity depen-dence. It is indicative that the astrophysical community does not find anyquantitative explanation to this dependence almost 100 years after as it wasdiscovered.

5. The discovering of the solar surface oscillations poses a new problem thatneeds a quantitative explanation.

6. There are measured data showing that a some stars are possessing by themagnetic fields. This date can be analyzed at taking into account of the electricpolarization inside these stars.

It seems that all measuring data are listed which can determine the correctchoice of the starting postulate. 3

It is important to underline that all above-enumerated dependencies areknown but they don’t have a quantitative (often even qualitative) explanationin frame of the standard theory based on Eq.(1.1). Usually one does not considerthe existence of these data as a possibility to check the theoretical constructions.Often they are ignored.

It will be shown below that all these dependencies obtain a quantitativeexplanation in the theory based on the postulate Eq.(1.3), which takes in toaccount the electric interaction between particles in the stellar plasma. At thatall basic measuring parameters of stars - masses, radii, temperatures - can bedescribed by definite rations of world constants, and it gives a good agreementwith measurement data.

3 From this point of view one can consider also the measurement of solar neutrino flux asone of similar phenomenon. But its result can be interpreted ambiguously because there area bad studied mechanism of their mutual conversation and it seems prematurely to use thismeasurement for a stellar models checking.

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Chapter 2

A hot dense plasma

2.1 The properties of a hot dense plasma

2.1.1 A hot plasma and Boltzman distribution

Free electrons being fermions obey the Fermi-Dirac statistic at low tempera-tures. At high temperatures, quantum distinctions in behavior of electron gasdisappear and it is possible to consider electron gas as the ideal gas which obeysthe Boltzmann statistics. At high temperatures and high densities, all sub-stances transform into electron-nuclear plasma. There are two tendencies inthis case. At temperature much higher than the Fermi temperature TF = EF

k(where EF is Fermi energy), the role of quantum effects is small. But their rolegrows with increasing of the pressure and density of an electron gas. Whenquantum distinctions are small, it is possible to describe the plasma electrongas as a the ideal one. The criterium of Boltzman’s statistics applicability

T ≫ EFk. (2.1)

hold true for a nonrelativistic electron gas with density 1025 particles in cm3 atT ≫ 106K.

At this temperatures, a plasma has energy

E =3

2kTN (2.2)

and its EOS is the ideal gas EOS:

P =NkT

V(2.3)

But even at so high temperatures, an electron-nuclear plasma can be consid-ered as ideal gas in the first approximation only. For more accurate descriptionits properties, the specificity of the plasma particle interaction must be takeninto account and two main corrections to ideal gas law must be introduced.

11

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12 CHAPTER 2. A HOT DENSE PLASMA

The first correction takes into account the quantum character of electrons,which obey the Pauli principle, and cannot occupy levels of energetic distribu-tion which are already occupied by other electrons. This correction must bepositive because it leads to an increased gas incompressibility.

Other correction takes into account the correlation of the screening actionof charged particles inside dense plasma. It is the so-called correlational cor-rection. Inside a dense plasma, the charged particles screen the fields of othercharged particles. It leads to a decreasing of the pressure of charged parti-cles. Accordingly, the correction for the correlation of charged particles mustbe negative,because it increases the compressibility of electron gas.

2.1.2 The hot plasma energy with taking into account thecorrection for the Fermi-statistic

The energy of the electron gas in the Boltzmann case (kT ≫ EF ) can be calcu-lated using the expression of the full energy of a non-relativistic Fermi-particlesystem [9]:

E =21/2V m

3/2e

π2~3

∫ ∞

0

ε3/2dε

e(ε−µe)/kT + 1, (2.4)

expanding it in a series. (me is electron mass, ε is the energy of electron andµe is its chemical potential).

In the Boltzmann case, µe < 0 and |µe/kT | ≫ 1 and the integrand ateµe/kT ≪ 1 can be expanded into a series according to powers eµe/kT−ε/kT . Ifwe introduce the notation z = ε

kT and conserve the two first terms of the series,we obtain

I ≡ (kT )5/2∫ ∞

0

z3/2dz

ez−µe/kT + 1≈

≈ (kT )5/2∫ ∞

0

z3/2(e

µekT

−z − e2(µekT

−z) + ...

)dz (2.5)

or

I

(kT )5/2≈ e

µekT Γ

(3

2+ 1

)− 1

25/2e

2µekT Γ

(3

2+ 1

)≈

≈ 3√π

4eµe/kT

(1− 1

25/2eµe/kT

). (2.6)

Thus, the full energy of the hot electron gas is

E ≈ 3V

2

(kT )5/2√2

(me

π~2

)3/2(eµe/kT − 1

25/2e2µe/kT

)(2.7)

Using the definition of a chemical potential of ideal gas (of particles withspin=1/2) [9]

µe = kT log

[Ne2V

(2π~2

mekT

)3/2](2.8)

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2.1. THE PROPERTIES OF A HOT DENSE PLASMA 13

we obtain the full energy of the hot electron gas

Ee ≈3

2kTNe

[1 +

π3/2

4

(aBe

2

kT

)3/2

ne

], (2.9)

where aB = ~2

mee2is the Bohr radius.

2.1.3 The correction for correlation of charged particlesin a hot plasma

At high temperatures, the plasma particles are uniformly distributed in space.At this limit, the energy of ion-electron interaction tends to zero. Some corre-lation in space distribution of particles arises as the positively charged particlegroups around itself preferably particles with negative charges and vice versa. Itis accepted to estimate the energy of this correlation by the method developedby Debye-Hukkel for strong electrolytes [9]. The energy of a charged particleinside plasma is equal to eϕ, where e is the charge of a particle, and ϕ is theelectric potential induced by other particles on the considered particle.

This potential inside plasma is determined by the Debye law [9]:

ϕ(r) =e

re− r

rD (2.10)

where the Debye radius is

rD =

(4πe2

kT

a

naZ2a

)−1/2

(2.11)

For small values of ratio rrD

, the potential can be expanded into a series

ϕ(r) =e

r− e

rD+ ... (2.12)

The following terms are converted into zero at r → 0. The first term of thisseries is the potential of the considered particle. The second term

E = −e3√

π

kTV

(∑

a

NaZ2a

)3/2

(2.13)

is a potential induced by other particles of plasma on the charge under consid-eration. And so the correlation energy of plasma consisting of Ne electrons and(Ne/Z) nuclei with charge Z in volume V is [9]

Ecorr = −e3√πnekT

(Z + 1)3/2

Ne (2.14)

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14 CHAPTER 2. A HOT DENSE PLASMA

2.2 The energetically preferable state of a hot

plasma

2.2.1 The energetically preferable density of a hot plasma

Finally, under consideration of both main corrections taking into account theinter-particle interaction, the full energy of plasma is given by

E ≈ 3

2kTNe

[1 +

π3/2

4

(aBe

2

kT

)3/2

ne −2π1/2

3

(Z + 1

kT

)3/2

e3n1/2e

](2.15)

The plasma into a star has a feature. A star generates the energy into itsinner region and radiates it from the surface. At the steady state of a star,its substance must be in the equilibrium state with a minimum of its energy.The radiation is not in equilibrium of course and can be considered as a starenvironment. The equilibrium state of a body in an environment is related tothe minimum of the function ([9]20):

E − ToS + PoV, (2.16)

where To and Po are the temperature and the pressure of an environment. Attaking in to account that the star radiation is going away into vacuum, the twolast items can be neglected and one can obtain the equilibrium equation of astar substance as the minimum of its full energy:

dEplasmadne

= 0. (2.17)

Now taking into account Eq.(2.15), one obtains that an equilibrium conditioncorresponds to the equilibrium density of the electron gas of a hot plasma

nequilibriume ≡ n⋆ =16

(Z + 1)3

a3B≈ 1.2 · 1024(Z + 1)3cm−3, (2.18)

It gives the electron density ≈ 3 · 1025cm−3 for the equilibrium state of the hotplasma of helium.

2.2.2 The estimation of temperature of energeticallypreferable state of a hot stellar plasma

As the steady-state value of the density of a hot non-relativistic plasma is known,we can obtain an energetically preferable temperature of a hot non-relativisticplasma.

The virial theorem [9, 18] claims that the full energy of particles E, if theyform a stable system with the Coulomb law interaction, must be equal to theirkinetic energy T with a negative sign. Neglecting small corrections at a hightemperature, one can write the full energy of a hot dense plasma as

Eplasma = U +3

2kTNe = −3

2kTNe. (2.19)

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2.2. THE ENERGETICALLY PREFERABLE STATE 15

Where U ≈ −GM2

R0is the potential energy of the system, G is the gravitational

constant, M and R0 are the mass and the radius of the star.As the plasma temperature is high enough, the energy of the black radiation

cannot be neglected. The full energy of the stellar plasma depending on theparticle energy and the black radiation energy

Etotal = −3

2kTNe +

π2

15

(kT

~c

)3

V kT (2.20)

at equilibrium state must be minimal, i.e.(∂Etotal∂T

)

N,V

= 0. (2.21)

This condition at Ne

V = n⋆ gives a possibility to estimate the temperature of thehot stellar plasma at the steady state:

T⋆ ≈ (Z + 1)~c

kaB≈ 107(Z + 1) K. (2.22)

The last obtained estimation can raise doubts. At ”terrestrial” conditions, theenergy of any substance reduces to a minimum at T → 0. It is caused by apositivity of a heat capacity of all of substances. But the steady-state energy ofstar is negative and its absolute value increases with increasing of temperature(Eq.(2.19)). It is the main property of a star as a thermodynamical object. Thiseffect is a reflection of an influence of the gravitation on a stellar substance andis characterized by a negative effective heat capacity. The own heat capacity ofa stellar substance (without gravitation) stays positive. With the increasing ofthe temperature, the role of the black radiation increases (Ebr ∼ T 4). When itsrole dominates, the star obtains a positive heat capacity. The energy minimumcorresponds to a point between these two branches.

2.2.3 Are accepted assumptions correct?

At expansion in series of the full energy of a Fermi-gas, it was supposed thatthe condition of applicability of Boltzmann-statistics (2.1) is valid. The substi-tution of obtained values of the equilibrium density n⋆ (2.18) and equilibriumtemperature T⋆ (2.22) shows that the ratio

EF (n⋆)kT⋆

≈ 3.1(Z + 1)α≪ 1. (2.23)

Where α ≈ 1137 is fine structure constant.

At appropriate substitution, the condition of expansion in series of the elec-tric potential (2.12) gives

r

rD≈ (n

1/3⋆ rD)

−1 ≈ α1/2 ≪ 1. (2.24)

Thus, obtained values of steady-state parameters of plasma are in full agreementwith assumptions which was made above.

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16 CHAPTER 2. A HOT DENSE PLASMA

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Chapter 3

The gravity induced electricpolarization in a dense hotplasma

3.1 Plasma cells

The existence of plasma at energetically favorable state with the constant den-sity n⋆ and the constant temperature T⋆ puts a question about equilibrium ofthis plasma in a gravity field. The Euler equation in commonly accepted formEq.(1.1) disclaims a possibility to reach the equilibrium in a gravity field at aconstant pressure in the substance: the gravity inevitably must induce a pres-sure gradient into gravitating matter. To solve this problem, it is necessaryto consider the equilibrium of a dense plasma in an gravity field in detail. Atzero approximation, at a very high temperature, plasma can be considered asa ”jelly”, where electrons and nuclei are ”smeared” over a volume. At a lowertemperature and a high density, when an interpartical interaction cannot beneglected, it is accepted to consider a plasma dividing in cells [12]. Nuclei areplaced at centers of these cells, the rest of their volume is filled by electron gas.Its density decreases from the center of a cell to its periphery. Of course, thisdividing is not freezed. Under action of heat processes, nuclei move. But havinga small mass, electrons have time to trace this moving and to form a permanentelectron cloud around nucleus, i.e. to form a cell. So plasma under action of agravity must be characterized by two equilibrium conditions:

- the condition of an equilibrium of the heavy nucleus inside a plasma cell;

- the condition of an equilibrium of the electron gas, or equilibrium of cells.

17

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18 CHAPTER 3. THE GRAVITY INDUCED ELECTRIC POLARIZATION

3.2 The equilibrium of a nucleus inside plasma

cell filled by an electron gas

At the absence of gravity, the negative charge of an electron cloud inside a cellexactly balances the positive charge of the nucleus at its center. Each cell isfully electroneutral. There is no direct interaction between nuclei.

The gravity acts on electrons and nuclei at the same time. Since the mass ofnuclei is large, the gravity force applied to them is much larger than the forceapplied to electrons. On the another hand, as nuclei have no direct interaction,the elastic properties of plasma are depending on the electron gas reaction. Thuser have a situation, when the force applied to nuclei must be balanced by theforce of the electron subsystem. The cell obtains an electric dipole moment ds,and the plasma obtains polarization P = ns ds, where ns is the density of thecell.

It is known [10], that the polarization of neighboring cells induces in theconsidered cell the electric field intensity

Es =4π

3P, (3.1)

and the cell obtains the energy

Es =ds Es2

. (3.2)

The gravity force applied to the nucleus is proportional to its mass Amp

(where A is a mass number of the nucleus, mp is the proton mass). The cellconsists of Z electrons, the gravity force applied to the cell electron gas is pro-portional to Zme (where me is the electron mass). The difference of these forcestends to pull apart centers of positive and negative charges and to increase thedipole moment. The electric field Es resists it. The process obtains equilibriumat the balance of the arising electric force ∇Es and the difference of gravityforces applied to the electron gas and the nucleus:

∇(2π

3

P2

ns

)+ (Amp − Zme)g = 0 (3.3)

Taking into account, that g = −∇ψ, we obtain

3

P2

ns= (Amp − Zme)ψ. (3.4)

Hence,

P2 =3GMr

2πrne

(A

Zmp −me

), (3.5)

where ψ is the potential of the gravitational field, ns =ne

Z is the density of cell(nuclei), ne is the density of the electron gas,Mr is the mass of a star containinginside a sphere with radius r.

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3.3. THE EQUILIBRIUM IN ELECTRON GAS SUBSYSTEM 19

3.3 The equilibrium in plasma electron gas sub-

system

Nonuniformly polarized matter can be represented by an electric charge distri-bution with density [10]

˜= divEs4π

=divP

3. (3.6)

The full electric charge of cells placed inside the sphere with radius r

Qr = 4π

∫ r

0

˜r2dr (3.7)

determinants the electric field intensity applied to a cell placed on a distance rfrom center of a star

E =Qrr2

(3.8)

As a result, the action of a nonuniformly polarized environment can be describedby the force ˜E. This force must be taken into account in the formulating ofequilibrium equation. It leads to the following form of the Euler equation:

γg+ ˜E+∇P = 0 (3.9)

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20 CHAPTER 3. THE GRAVITY INDUCED ELECTRIC POLARIZATION

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Chapter 4

The internal structure of astar

It was shown above that the state with the constant density is energeticallyfavorable for a plasma at a very high temperature. The plasma in the centralregion of a star can possess by this property . The calculation made below showsthat the mass of central region of a star with the constant density - the star core- is equal to 1/2 of the full star mass. Its radius is approximately equal to 1/10of radius of a star, i.e. the core with high density take approximately 1/1000part of the full volume of a star. The other half of a stellar matter is distributedover the region placed above the core. It has a relatively small density and itcould be called as a star atmosphere.

4.1 The plasma equilibrium in the star core

In this case, the equilibrium condition (Eq.(3.3)) for steady density plasma isachieved at

P =√Gγ⋆r, (4.1)

Here the mass density is γ⋆ ≈ AZmpn⋆. The polarized state of the plasma can

be described by a state with an electric charge at the density

˜= 1

3divP =

√Gγ⋆, (4.2)

and the electric field applied to a cell is

E =g√G. (4.3)

As a result, the electric force applied to the cell will fully balance the gravityaction

γg+ ˜E = 0 (4.4)

21

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22 CHAPTER 4. THE INTERNAL STRUCTURE OF A STAR

at the zero pressure gradient∇P = 0. (4.5)

4.2 The main parameters of a star core (in order

of values)

At known density n⋆ of plasma into a core and its equilibrium temperatureT⋆, it is possible to estimate the mass M⋆ of a star core and its radius R⋆. Inaccordance with the virial theorem1, the kinetic energy of particles composingthe steady system must be approximately equal to its potential energy withopposite sign:

GM2⋆

R⋆≈ kT⋆N⋆. (4.6)

Where N⋆ =4π3 R

3⋆n⋆ is full number of particle into the star core.

With using determinations derived above (2.18) and (2.22) derived before,we obtain

M⋆ ≈MCh

(A/Z)2(4.7)

where MCh =(

~cGm2

p

)3/2mp is the Chandrasekhar mass.

The radius of the core is approximately equal

R⋆ ≈(

~c

Gm2p

)1/2aB

(Z + 1)A/Z. (4.8)

where A and Z are the mass and the charge number of atomic nuclei the plasmaconsisting of.

4.3 The equilibrium state of the plasma inside

the star atmosphere

The star core is characterized by the constant mass density, the charge density,the temperature and the pressure. At a temperature typical for a star core,the plasma can be considered as ideal gas, as interactions between its particlesare small in comparison with kT⋆. In atmosphere, near surface of a star, thetemperature is approximately by 3 ÷ 4 orders smaller. But the plasma densityis lower. Accordingly, interparticle interaction is lower too and we can continueto consider this plasma as ideal gas.

In the absence of the gravitation, the equilibrium state of ideal gas in somevolume comes with the pressure equalization, i.e. with the equalization of itstemperature T and its density n. This equilibrium state is characterized by theequalization of the chemical potential of the gas µ (Eq.(2.8)).

1Below we shell use this theorem in its more exact formulation.

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4.4. THE RADIAL DEPENDENCE OF DENSITY AND TEMPERATURE23

4.4 The radial dependence of density and tem-

perature of substance inside a star atmo-sphere

For the equilibrium system, where different parts have different temperatures,the following relation of the chemical potential of particles to its temperatureholds ([9],25):

µ

kT= const (4.9)

As thermodynamic (statistical) part of chemical potential of monoatomic idealgas is [9],45:

µT = kT ln

[n

2

(2π~2

mkT

)3/2], (4.10)

we can conclude that at the equilibrium

n ∼ T 3/2. (4.11)

In external fields the chemical potential of a gas [9]25 is equal to

µ = µT + Epotential (4.12)

where Epotential is the potential energy of particles in the external field. There-fore in addition to fulfillment of condition Eq. (4.11), in a field with Coulombpotential, the equilibrium needs a fulfillment of the condition

− GMrγ

rkTr+

P2r

2kTr= const (4.13)

(where m is the particle mass, Mr is the mass of a star inside a sphere withradius r, Pr and Tr are the polarization and the temperature on its surface. Ason the core surface, the left part of Eq.(4.13) vanishes, in the atmosphere

Mr ∼ rkTr. (4.14)

Supposing that a decreasing of temperature inside the atmosphere is a powerfunction with the exponent x, its value on a radius r can be written as

Tr = T⋆

(R⋆

r

)x(4.15)

and in accordance with (4.11), the density

nr = n⋆

(R⋆

r

)3x/2

. (4.16)

Setting the powers of r in the right and the left parts of the condition (4.14)equal, one can obtain x = 4.

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24 CHAPTER 4. THE INTERNAL STRUCTURE OF A STAR

Thus, at using power dependencies for the description of radial dependenciesof density and temperature, we obtain

nr = n⋆

(R⋆

r

)6

(4.17)

and

Tr = T⋆

(R⋆

r

)4

. (4.18)

4.5 The mass of the star atmosphere and the

full mass of a star

After integration of (4.17), we can obtain the mass of the star atmosphere

MA = 4π

∫R0

R⋆

(A/Z)mpn⋆

(R⋆

r

)6

r2dr =4π

3(A/Z)mpn⋆R⋆

3

[1−

(R⋆

R0

)3]

(4.19)

It is equal to its core mass (toR

3⋆

R30

≈ 10−3), where R0 is radius of a star.

Thus, the full mass of a star

M = MA +M⋆ ≈ 2M⋆ (4.20)

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Chapter 5

The virial theorem andmain parameters of a star

5.1 The energy of a star

The virial theorem [9, 18] is applicable to a system of particles if they have afinite moving into a volume V . If their interaction obeys to the Coulomb’s law,their potential energy Epotential, their kinetic energy Ekinetic and pressure P arein the ratio:

2Ekinetic + Epotential = 3PV. (5.1)

On the star surface, the pressure is absent and for the particle system as awhole:

2Ekinetic = −Epotential (5.2)

and the full energy of plasma particles into a star

E(plasma) = Ekinetic + Epotential = −Ekinetic. (5.3)

Let us calculate the separate items composing the full energy of a star.

5.1.1 The kinetic energy of plasma

The kinetic energy of plasma into a core:

Ekinitic⋆ =3

2kT⋆N⋆. (5.4)

The kinetic energy of atmosphere:

Ekinetica = 4π

∫ R0

R⋆

3

2kT⋆n⋆

(R⋆

r

)10

r2dr ≈ 3

7

(3

2kT⋆N⋆

)(5.5)

The total kinetic energy of plasma particles

Ekinetic = Ekinetic⋆ + Ekinetica =15

7kT⋆N⋆ (5.6)

25

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26 CHAPTER 5. THE MAIN PARAMETERS OF STAR

5.1.2 The potential energy of star plasma

Inside a star core, the gravity force is balanced by the force of electric nature.Correspondingly, the energy of electric polarization can be considered as bal-anced by the gravitational energy of plasma. As a result, the potential energyof a core can be considered as equal to zero.

In a star atmosphere, this balance is absent.The gravitational energy of an atmosphere

EGa = −4πGM⋆A

Zmpn⋆

∫ R0

R⋆

1

2

[2−

(R⋆

r

)3](

R⋆

r

)6

rdr (5.7)

or

EGa =3

2

(1

7− 1

2

)GM2

R⋆= −15

28

GM2⋆

R⋆(5.8)

The electric energy of atmosphere is

EEa = −4π

∫ R0

R⋆

1

2ϕr2dr, (5.9)

where

˜= 1

3r2dPr2

dr(5.10)

and

ϕ =4π

3Pr. (5.11)

The electric energy:

EEa = − 3

28

GM2⋆

R⋆, (5.12)

and total potential energy of atmosphere:

Epotentiala = EGa + EEa = − 9

14

GM2⋆

R⋆. (5.13)

The equilibrium in a star depends both on plasma energy and energy of radia-tion.

5.2 The temperature of a star core

5.2.1 The energy of the black radiation

The energy of black radiation inside a star core is

E⋆(br) =π2

15kT⋆

(kT⋆~c

)3

V⋆. (5.14)

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5.3. MAIN STAR PARAMETERS 27

The energy of black radiation inside a star atmosphere is

Ea(br) = 4π

∫ R0

R⋆

π2

15kT⋆

(kT⋆~c

)3(R⋆

r

)16

r2dr =3

13

π2

15kT⋆

(kT⋆~c

)3

V⋆.

(5.15)The total energy of black radiation inside a star is

E(br) = E⋆(br) + Ea(br) =16

13

π2

15kT⋆

(kT⋆~c

)3

V⋆ = 1.23π2

15kT⋆

(kT⋆~c

)3

V⋆

(5.16)

5.2.2 The full energy of a star

In accordance with (5.3), the full energy of a star

Estar = −Ekinetic + E(br) (5.17)

i.e.

Estar = −15

7kT⋆N⋆ +

16

13

π2

15kT⋆

(kT⋆~c

)3

V⋆. (5.18)

The steady state of a star is determined by a minimum of its full energy:(dEstardT⋆

)

N=const,V=const

= 0, (5.19)

it corresponds to the condition:

− 15

7N⋆ +

64π2

13 · 15

(kT⋆~c

)3

V⋆ = 0. (5.20)

Together with Eq.(2.18) it defines the equilibrium temperature of a star core:

T⋆ =

(25 · 1328π4

)1/3(~c

kaB

)(Z + 1) ≈ (Z + 1) · 2.13 · 107K (5.21)

5.3 Main star parameters

5.3.1 The star mass

The virial theorem relates kinetic energy of a system with its potential energy.In accordance with Eqs.(5.13) and (5.6)

9

14

GM2⋆

R⋆=

30

7kT⋆N⋆. (5.22)

Introducing the non-dimensional parameter

β =GM⋆

AZmp

R⋆kT⋆, (5.23)

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28 CHAPTER 5. THE MAIN PARAMETERS OF STAR

we obtain

β =20

3= 6.67, (5.24)

and at taking into account Eqs.(2.18) and (5.21), the core mass is

M⋆ =

[20

3

(25 · 1328

)1/33

4 · 3.14

]3/2MCh(AZ

)2 = 6.84MCh(AZ

)2 (5.25)

The obtained equation plays a very important role, because together withEq.(4.20), it gives a possibility to predict the total mass of a star:

M = 2M⋆ =13.68MCh(

AZ

)2 ≈ 25.34M⊙(AZ

)2 . (5.26)

The comparison of obtained prediction Eq.(5.26) with measuring data givesa method to check our theory. Although there is no way to determine chemicalcomposition of cores of far stars, some predictions can be made in this way. Atfirst, there must be no stars which masses exceed the mass of the Sun by morethan one and a half orders, because it accords to limiting mass of stars consistingfrom hydrogen with A/Z = 1. Secondly, the action of a specific mechanism (see.Sec.11) can make neutron-excess nuclei stable, but it don’t give a base to supposethat stars with A/Z > 10 (and with mass in hundred times less than hydrogenstars) can exist. Thus, the theory predicts that the whole mass spectrum mustbe placed in the interval from 0.25 up to approximately 25 solar masses. Thesepredications are verified by measurements quite exactly. The mass distributionof binary stars1 is shown in Fig.5.1 [7].

Besides, one can see the presence of separate peaks for stars with A/Z =3; 4; 5... and with A/Z = 3/2 in Fig.5.1. At that it is important to note, thataccording to Eq.(5.26) the Sun must consist from a substance with A/Z = 5.This conclusion is in a good agreement with results of consideration of solaroscillations (Chapter 9). The mass spectrum of close binary stars2 is shown inFig.5.2. It does not contain stars with high parameter A/Z, but it is importantthat both spectra - those of binary stars and those of close binary stars - comeabruptly to the end near A/Z = 1.

5.3.2 Radii of stars

Using Eq.(2.18) and Eq.(5.25), we can determine the star core radius:

R⋆ =3(6.84π)1/3

4(Z + 1)A/ZaB

(~c

Gm2p

)1/2

≈ 1.41 · 1011(Z + 1)A/Z

cm. (5.27)

1The use of these data is caused by the fact that only the measurement of parameters ofbinary star rotation gives a possibility to determine their masses with satisfactory accuracy.

2The data of these measurements were obtained in different observatories of the world. Thelast time the summary table with these data was gathered by Khaliulilin Kh.F. (SternbergAstronomical Institute) [8] in his dissertation (in Russian) which has unfortunately has a re-stricted access. With his consent and for readers convenience, we place that table in Appendixon http://astro07.narod.ru.

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5.3. MAIN STAR PARAMETERS 29

-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0log M/Mo

0

5

10

15

20

25

30

35

40

N

2 1 A/Z 6 5 4 378910

1.5

.

Figure 5.1: The mass distribution of binary stars [7]. On abscissa, the logarithmof the star mass over the Sun mass is shown. Solid lines mark masses, whichagree with selected values of A/Z from Eq.(5.26).

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30 CHAPTER 5. THE MAIN PARAMETERS OF STAR

-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0log M/Mo

0

5

10

15

20

25

30

35

40

N

2 1 A/Z 6 5 4 378910

1.5

.binary stars close binary stars

Figure 5.2: The mass distribution of close binary stars [8]. On abscissa, thelogarithm of the star mass over the Sun mass is shown. Solid lines mark masses,which agree with selected values of A/Z from Eq.(5.26). The binary star spec-trum is shown for comparison.

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5.3. MAIN STAR PARAMETERS 31

The temperature near the star surface is relatively small. It is approximatelyby 3 orders smaller than it is inside the core. Because of it at calculation ofsurface parameters, we must take into consideration effects of this order, i.e. itis necessary to take into account the gravity action on the electron gas. At thatit is convenient to consider the plasma cell as some neutral quasi-atom (like theThomas-Fermi atom). Its electron shell is formed by a cloud of free electrons.

Each such quasi-atom is retained on the star surface by its negative potentialenergy

(Egravitational + Eelectric) < 0. (5.28)

The electron cloud of the cell is placed in the volume δV = 4π3 r

3s , (where rs ≈(

Zne

)1/3) under pressure Pe. The evaporation of plasma cell releases energy

EPV = PeVs, and the balance equation takes the form:

Egravitational + Eelectric + EPV = 0. (5.29)

In cold plasma, the electron cloud of the cell has energy EPV ≈ e2ne1/3. in very

hot plasma at kT ≫ Z2e2

rs, this energy is equal to EPV = 3

2ZkT . On the starsurface these energies are approximately equal:

kT0

e2n1/3e

≈ 1

α

(R0

R⋆

)2

≈ 1. (5.30)

One can show it easily, that in this case

EPV ≈ 2Z

√3

2kT · e2ne1/3. (5.31)

And if to take into account Eqs.(4.17)-(4.18), we obtain

EPV ≈ 1.5ZkT⋆

(R⋆

R0

)3 √απ (5.32)

The energy of interaction of a nucleus with its electron cloud does not changeat evaporation of the cell and it can be neglected. Thus, for the surface

Eelectric =2πP2

3ns=

2GM⋆

R0(Amp − Zme) . (5.33)

The gravitational energy of the cell on the surface

Egravitational = −2GM⋆

R0(Amp + Zme) . (5.34)

Thus, the balance condition Eq.(5.29) on the star surface obtains the form

− 4GM⋆Zme

R0+ 1.5ZkT⋆

(R⋆

R0

)3 √απ = 0. (5.35)

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32 CHAPTER 5. THE MAIN PARAMETERS OF STAR

5.3.3 The R⋆/R0 ratio and R0

With account of Eq.(4.18) and Eqs.(5.24)-(5.23), we can write

R0

R⋆=

(√απ

AZmp

me

)1/2

≈ 4.56

√A

Z(5.36)

As the star core radius is known Eq.(5.27), we can obtain the star surface radius:

R0 ≈ 6.44 · 1011(Z + 1)(A/Z)1/2

cm (5.37)

5.3.4 The temperature of a star surface

At known Eq.(4.18) and Eq.(5.21), we can calculate the temperature of externalsurface of a star

T0 = T⋆

(R⋆

R0

)4

≈ 4.92 · 105 (Z + 1)

(A/Z)2(5.38)

5.3.5 The comparison with measuring data

The solar oscillations (see Chapter(9)) show that the Sun consists basically fromhelium-10 with Z = 2, A/Z = 5. With account of this

R0(Z = 2, A/Z = 5) = 9.59 · 1010cm, (5.39)

it differs from the measured value of the Sun radius

R⊙ = 6.96 · 1010cm. (5.40)

It can be a consequence of the estimation of the core radius from Eq.(5.27) atZ = 2, A/Z = 5 gives R⋆(Z = 2, A/Z = 5) = 9.6 · 109cm, and the ratio ofmeasured radius of the Sun to the calculated value of the core radius is equal

R⊙

R⋆(Z = 2, A/Z = 5)≈ 7.24, (5.41)

where as the calculation Eq.(5.36) gives

R0

R⋆(Z = 2, A/Z = 5)≈ 10.2 (5.42)

At the same time, the calculated value of surface temperature of the Sun(Eq.(5.38)),

T0 ≈ 5911K (5.43)

is in a good agreement with its measured value (T⊙ ≈ 5850K).The calculation shows that the mass of core of the Sun

M⋆(Z = 2, A/Z = 5) ≈ 9.68 · 1032 g (5.44)

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5.3. MAIN STAR PARAMETERS 33

i.t. almost exactly equals to one half of full mass of the Sun

M⋆(Z = 2, A/Z = 5)

M⊙

≈ 0.486 (5.45)

in full agreement with Eq.(4.20).

In addition to obtained determinations of the mass of a star Eq.(5.26), itstemperature Eq.(5.38) and its radius Eq.(5.37) give possibility to check the cal-culation, if we compare these results with measuring data. Really, dependenciesmeasured by astronomers can be described by functions:

M =Const1(A/Z)2

, (5.46)

R0 =Const2

(Z + 1)(A/Z)1/2, (5.47)

T0 =Const3(Z + 1)

(A/Z)2. (5.48)

If to combine they in the way, to exclude unknown parameter (Z + 1), one canobtain relation:

T0R0 = ConstM5/4, (5.49)

Its accuracy can by checked. For this checking, let us use the measuring dataof parameters of masses, temperatures and radii of close binary stars [8]. Theresults of these measurements are shown in Fig.(5.3), where the dependenceaccording to Eq.(5.49). It is not difficult to see that these data are well de-scribed by the calculated dependence. It speaks about successfulness of ourconsideration.

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34 CHAPTER 5. THE MAIN PARAMETERS OF STAR

-0.2 0.1 0.4 0.7 1.0 1.3 1.6-0.10

0.45

1.00

1.55

2.10

measured

TR~M1.27

theory

TR~M 5/4

log (TR/RoTo)

logM/M o

Figure 5.3: The relation between main parameters of stars (Eq.(5.49)) andcorresponding data of astronomical measurements for close binary stars [8] areshown.

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Chapter 6

The thermodynamicrelations of intrastellarplasma

6.1 The thermodynamic relation of star atmo-sphere parameters

Hot stars steadily generate energy and radiate it from their surfaces. This is non-equilibrium radiation in relation to a star. But it may be a stationary radiationfor a star in steady state. Under this condition, the star substance can be con-sidered as an equilibrium. This condition can be considered as quasi-adiabatic,because the interchange of energy between both subsystems - radiation andsubstance - is stationary and it does not result in a change of entropy of sub-stance. Therefore at consideration of state of a star atmosphere, one can baseit on equilibrium conditions of hot plasma and the ideal gas law for adiabaticcondition can be used for it in the first approximation.

It is known, that thermodynamics can help to establish correlation betweensteady-state parameters of a system. Usually, the thermodynamics considerssystems at an equilibrium state with constant temperature, constant particledensity and constant pressure over all system. The characteristic feature ofthe considered system is the existence of equilibrium at the absence of a con-stant temperature and particle density over atmosphere of a star. To solve thisproblem, one can introduce averaged pressure

P ≈ GM2

R40

, (6.1)

averaged temperature

T =

∫VTdV

V∼ T0

(R0

R⋆

)(6.2)

35

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36 CHAPTER 6. THE THERMODYNAMIC RELATIONS

and averaged particle density

n ≈ NA

R30

(6.3)

After it by means of thermodynamical methods, one can find relation betweenparameters of a star.

6.1.1 The cP/cV ratio

At a movement of particles according to the theorem of the equidistribution,the energy kT/2 falls at each degree of freedom. It gives the heat capacitycv = 3/2k.

According to the virial theorem [9, 18], the full energy of a star shouldbe equal to its kinetic energy (with opposite sign)(Eq.(5.3)), so as full energyrelated to one particle

E = −3

2kT (6.4)

In this case the heat capacity at constant volume (per particle over Boltzmanconstant k) by definition is

cV =

(dE

dT

)

V

= −3

2(6.5)

The negative heat capacity of stellar substance is not surprising. It is a knownfact and it is discussed in Landau-Lifshitz course [9]. The own heat capacityof each particle of star substance is positive. One obtains the negative heatcapacity at taking into account the gravitational interaction between particles.

By definition the heat capacity of an ideal gas particle at permanent pressure[9] is

cP =

(dW

dT

)

P

, (6.6)

where W is enthalpy of a gas.

As for the ideal gas [9]

W − E = NkT, (6.7)

and the difference between cP and cV

cP − cV = 1. (6.8)

Thus in the case considered, we have

cP = −1

2. (6.9)

Supposing that conditions are close to adiabatic ones, we can use the equationof the Poisson’s adiabat.

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6.2. THE MASS-RADIUS RATIO 37

6.1.2 The Poisson’s adiabat

The thermodynamical potential of a system consisting of N molecules of idealgas at temperature T and pressure P can be written as [9]:

Φ = const ·N +NT lnP −NcPT lnT. (6.10)

The entropy of this system

S = const ·N −NlnP +NcP lnT. (6.11)

As at adiabatic process, the entropy remains constant

−NT lnP +NcPT lnT = const, (6.12)

we can write the equation for relation of averaged pressure in a system with itsvolume (The Poisson’s adiabat) [9]:

P V eγ = const, (6.13)

where γ = cPcV

is the exponent of adiabatic constant. In considered case takinginto account of Eqs.(6.6) and (6.5), we obtain

γ =cPcV

=1

3. (6.14)

As V 1/3 ∼ R0, we have for equilibrium condition

PR0 = const. (6.15)

6.2 The mass-radius ratio

Using Eq.(6.1) from Eq.(6.15), we use the equation for dependence of masses ofstars on their radii:

M2

R30

= const (6.16)

This equation shows the existence of internal constraint of chemical parametersof equilibrium state of a star. Indeed, the substitution of obtained determina-tions Eq.(5.37) and (5.38)) into Eq.(6.16) gives:

(1 + Z) ∼ (A/Z)5/6 (6.17)

Simultaneously the observational data of masses, of radii and their temperatureswas obtained by astronomers for close binary stars [8]. The dependence of radiiof these stars over these masses is shown in Fig.6.1 on double logarithmic scale.The solid line shows the result of fitting of measurement data R0 ∼ M

0.68. It isclose to theoretical dependence R0 ∼ M

2/3 (Eq.6.16) which is shown by dottedline.

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38 CHAPTER 6. THE THERMODYNAMIC RELATIONS

-0.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 log M/M o

-0.1

0.1

0.3

0.5

0.7

0.9

1.1

1.3

1.5log R/R o

theory

R~M2/3

measured

R~M0.68

Figure 6.1: The dependence of radii of stars over the star mass [8]. Here theradius of stars is normalized to the sunny radius, the stars masses are normalizedto the mass of the Sum. The data are shown on double logarithmic scale. Thesolid line shows the result of fitting of measurement data R0 ∼ M

0.68. Thetheoretical dependence R0 ∼ M

2/3 (6.16) is shown by the dotted line.

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6.3. THE MASS-TEMPERATURE-LUMINOSITY RELATIONS 39

6.3 The mass-temperature and mass-luminosity

relations

Taking into account Eqs.(4.18), (2.22) and (4.8) one can obtain the relationbetween surface temperature and the radius of a star

T0 ∼ R7/80 , (6.18)

or accounting for (6.16)T0 ∼ M

7/12 (6.19)

The dependence of the temperature on the star surface over the star mass ofclose binary stars [8] is shown in Fig.(6.2). Here the temperatures of stars arenormalized to the sunny surface temperature (5875 C), the stars masses arenormalized to the mass of the Sum. The data are shown on double logarithmicscale. The solid line shows the result of fitting of measurement data (T0 ∼M

0.59). The theoretical dependence T0 ∼ M7/12 (Eq.6.19) is shown by dotted

line.The luminosity of a star

L0 ∼ R20T

40. (6.20)

at taking into account (Eq.6.16) and (Eq.6.19) can be expressed as

L0 ∼ M11/3 ∼ M

3.67 (6.21)

This dependence is shown in Fig.(6.3) It can be seen that all calculated inter-dependencies R(M),T(M) and L(M) show a good qualitative agreement withthe measuring data. At that it is important, that the quantitative explanationof mass-luminosity dependence discovered at the beginning of 20th century isobtained.

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40 CHAPTER 6. THE THERMODYNAMIC RELATIONS

-0.1 0.1 0.3 0.5 0.7 0.9 1.1 1.3 1.5

log M/Mo

-0.1

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

log T/To

measured

T~M0.59

theory

T~M7/12

Figure 6.2: The dependence of the temperature on the star surface over the starmass of close binary stars [8]. Here the temperatures of stars are normalized tosurface temperature of the Sun (5875 C), the stars masses are normalized to themass of Sum. The data are shown on double logarithmic scale. The solid lineshows the result of fitting of measurement data (T0 ∼ M

0.59). The theoreticaldependence T0 ∼ M

7/12 (Eq.6.19) is shown by dotted line.

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6.3. THE MASS-TEMPERATURE-LUMINOSITY RELATIONS 41

-0.1 0.1 0.3 0.5 0.7 0.9 1.1 1.3 1.5-1

0

1

2

3

4

5

6

theory

L~M11/3

measured

L~M3.74

log L/Lo

log M/Mo

Figure 6.3: The dependence of star luminosity on the star mass of close binarystars [8]. The luminosities are normalized to the luminosity of the Sun, the starsmasses are normalized to the mass of the Sum. The data are shown on doublelogarithmic scale. The solid line shows the result of fitting of measurement dataL ∼ M

3.74. The theoretical dependence L ∼ M11/3 (Eq.6.21) is shown by dotted

line.

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42 CHAPTER 6. THE THERMODYNAMIC RELATIONS

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Chapter 7

Magnetic fields andmagnetic moments of stars

7.1 Magnetic moments of celestial bodies

A thin spherical surface with radius r carrying an electric charge q at the rotationaround its axis with frequency Ω obtains the magnetic moment

m =r2

3cqΩ. (7.1)

The rotation of a ball charged at density (r) will induce the magnetic moment

µ =Ω

3c

∫ R

0

r2(r) 4πr2dr. (7.2)

Thus the positively charged core of a star induces the magnetic moment

m+ =

√GM⋆R

2⋆

5cΩ. (7.3)

A negative charge will be concentrated in the star atmosphere. The absolutevalue of atmospheric charge is equal to the positive charge of a core. As theatmospheric charge is placed near the surface of a star, its magnetic momentwill be more than the core magnetic moment. The calculation shows that asa result, the total magnetic moment of the star will have the same order ofmagnitude as the core but it will be negative:

mΣ ≈ −√G

cM⋆R

2⋆Ω. (7.4)

Simultaneously, the torque of a ball with mass M and radius R is

L ≈ M⋆R2⋆Ω. (7.5)

43

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44 CHAPTER 7. MAGNETIC FIELDS OF STARS

As a result, for celestial bodies where the force of their gravity induces theelectric polarization according to Eq.(4.2), the giromagnetic ratio will dependon world constants only:

L≈ −

√G

c. (7.6)

This relation was obtained for the first time by P.M.S.Blackett [3]. He showsthat giromagnetic ratios of the Earth, the Sun and the star 78 Vir are reallynear to

√G/c.

By now the magnetic fields, masses, radii and velocities of rotation are knownfor all planets of the Solar system and for a some stars [15]. These measuringdata are shown in Fig.(7.1), which is taken from [15]. It is possible to seethat these data are in satisfactory agreement with Blackett’s ratio. At someassumption, the same parameters can be calculated for pulsars. All measuredmasses of pulsars are equal by the order of magnitude [17]. It is in satisfactoryagreement with the condition of equilibrium of relativistic matter (see ). Itgives a possibility to consider that masses and radii of pulsars are determined.According to generally accepted point of view, pulsar radiation is related withits rotation, and it gives their rotation velocity. These assumptions permit tocalculate the giromagnetic ratios for three pulsars with known magnetic fieldson their poles [2]. It is possible to see from Fig.(7.1), the giromagnetic ratios ofthese pulsars are in agreement with Blackett’s ratio.

7.2 Magnetic fields of hot stars

To make the above rough estimation for magnetic fields induced by the staratmosphere more accurate, we can take into account the distribution of electriccharges inside the star atmosphere In accordance with this distribution, theatmosphere at its rotation induces the moment

m− = −√GM⋆ΩR⋆

2

9c

∫ R0

R⋆

r2d

dr

√ξ3(2 − ξ3) dr, (7.7)

Where ξ = R⋆

r .As R⋆ ≪ R0, the magnetic moment of a core can be neglected. In this case,

the total magnetic moment of a star

m ≈ −2

√GM⋆

3c

(R

7/20

R3/2⋆

)Ω. (7.8)

and magnetic field near the pole of a star

H ≈ −2√GM⋆

9c

R1/20

R3/2⋆

Ω. (7.9)

Using of substitution of relations obtained above, one can conclude that themagnetic field on a star pole must not depend on the parameter (Z + 1) and

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7.2. MAGNETIC FIELDS OF STARS 45

30 40 50 60Log L15

25

35

45

Log

µ

Pluto

TitanMercury

Io Venus

Mars

Earth

Uranus

Neptun Saturn

Sun

JupiterPsr 4U0115+13

Psr Her X-1Psr 0531+21

78 Vir

µ/L=G

1/2 /c

Figure 7.1: The observed values of magnetic moments of celestial bodies vs.their angular momenta [15]. In ordinate, the logarithm of the magnetic moment(in Gs · cm3) is plotted; in abscissa the logarithm of the angular momentum (inerg · s) is shown. The solid line illustrates Eq.(7.6). The dash-dotted line fits ofobserved values.

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46 CHAPTER 7. MAGNETIC FIELDS OF STARS

very slightly depends on A/Z, and this dependence can be neglected. I.e. thecalculations show that this field practically is not depending on the mass, on theradius and on the temperature of a hot star and must depend on the velocityof star rotation only:

H ≈ −0.47

(me

mp

)3/4αc

G1/2β1/4Ω ≈ −8.8 · 108Ω Oe. (7.10)

The magnetic fields are measured for stars of Ap-class [13]. These stars arecharacterized by changing their brightness in time. The periods of these changesare measured too. At present there is no full understanding of causes of thesevisible changes of the luminosity. If these luminosity changes caused by someinternal reasons will occur not uniformly on a star surface, one can conclude thatthe measured period of the luminosity change can depend on star rotation. It ispossible to think that at relatively rapid rotation of a star, the period of a visiblechange of the luminosity can be determined by this rotation in general. Tocheck this suggestion, we can compare the calculated dependence (Eq.7.10) withmeasuring data [13] (see Fig. 7.2). It can be seen that if magnetic fields of hotstars are really described by the mechanism considered, there are unaccountedfactors in this model. It should be said that Eq.(7.10) does not working well incase with the Sun. The Sun surface rotates with period T ≈ 25÷30 days. At thisvelocity of rotation, the magnetic field on the Sun pole calculated accordinglyto Eq.(7.10) must be about 1 kOe. The dipole field of Sun according to expertsestimation is approximately 20 times lower. There can be several reasons forthat.

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7.2. MAGNETIC FIELDS OF STARS 47

0 1 2 3 4 5

W

0

10

20

30

40

50

60

70

80

90

100

H,kOe

10. 5, s

-1

V 901 Ori

HR 7129

33 Lib

GL Lac

Figure 7.2: The dependence of magnetic fields on poles of Ap-stars as a functionof their rotation velocity [13]. The line shows Eq.(7.10)).

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48 CHAPTER 7. MAGNETIC FIELDS OF STARS

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Chapter 8

The angular velocity of theapsidal rotation in binarystars

8.1 The apsidal rotation of close binary stars

The apsidal rotation (or periastron rotation) of close binary stars is a resultof their non-Keplerian movement which originates from the non-spherical formof stars. This non-sphericity has been produced by rotation of stars aroundtheir axes or by their mutual tidal effect. The second effect is usually smallerand can be neglected. The first and basic theory of this effect was developedby A.Clairault at the beginning of the XVIII century. Now this effect wasmeasured for approximately 50 double stars. According to Clairault’s theorythe velocity of periastron rotation must be approximately 100 times faster ifmatter is uniformly distributed inside a star. Reversely, it would be absent if allstar mass is concentrated in the star center. To reach an agreement between themeasurement data and calculations, it is necessary to assume that the density ofsubstance grows in direction to the center of a star and here it runs up to a valuewhich is hundreds times greater than mean density of a star. Just the same massconcentration of the stellar substance is supposed by all standard theories of astar interior. It has been usually considered as a proof of astrophysical models.But it can be considered as a qualitative argument. To obtain a quantitativeagreement between theory and measurements, it is necessary to fit parametersof the stellar substance distribution in each case separately.

Let us consider this problem with taking into account the gravity inducedelectric polarization of plasma in a star. As it was shown above, one half offull mass of a star is concentrated in its plasma core at a permanent density.Therefor, the effect of periastron rotation of close binary stars must be reviewedwith the account of a change of forms of these star cores.

49

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50 CHAPTER 8. THE APSIDAL ROTATION

According to [4],[14] the ratio of the angular velocity ω of rotation of pe-riastron which is produced by the rotation of a star around its axis with theangular velocity Ω is

ω

Ω=

3

2

(IA − IC)

Ma2(8.1)

where IA and IC are the moments of inertia relatively to principal axes of theellipsoid. Their difference is

IA − IC =M

5(a2 − c2), (8.2)

where a and c are the equatorial and polar radii of the star.Thus we have

ω

Ω≈ 3

10

(a2 − c2)

a2. (8.3)

8.2 The equilibrium form of the core of a rotat-

ing star

In the absence of rotation the equilibrium equation of plasma inside star core(Eq.4.4 is

γgG + ρGEG = 0 (8.4)

where γ,gG, ρG and EG are the substance density the acceleration of gravitation,gravity-induced density of charge and intensity of gravity-induced electric field(div gG = 4π G γ, div EG = 4πρG and ρG =

√Gγ).

One can suppose, that at rotation, under action of a rotational accelerationgΩ, an additional electric charge with density ρΩ and electric field EΩ can exist,and the equilibrium equation obtains the form:

(γG + γΩ)(gG + gΩ) = (ρG + ρΩ)(EG + EΩ), (8.5)

where

div (EG +EΩ) = 4π(ρG + ρΩ) (8.6)

or

div EΩ = 4πρΩ. (8.7)

We can look for a solution for electric potential in the form

ϕ = CΩ r2(3cos2θ − 1) (8.8)

or in Cartesian coordinates

ϕ = CΩ(3z2 − x2 − y2 − z2) (8.9)

where CΩ is a constant.

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8.2. THE EQUILIBRIUM FORM OF THE CORE 51

Thus

Ex = 2 CΩ x, Ey = 2 CΩ y, Ez = −4 CΩ z (8.10)

and

div EΩ = 0 (8.11)

and we obtain important equations:

ρΩ = 0; (8.12)

γgΩ = ρEΩ. (8.13)

Since centrifugal force must be contra-balanced by electric force

γ 2Ω2 x = ρ 2CΩ x (8.14)

and

CΩ =γ Ω2

ρ=

Ω2

√G

(8.15)

The potential of a positive uniform charged ball is

ϕ(r) =Q

R

(3

2− r2

2R2

)(8.16)

The negative charge on the surface of a sphere induces inside the sphere thepotential

ϕ(R) = −QR

(8.17)

where according to Eq.(8.4) Q =√GM , and M is the mass of the star.

Thus the total potential inside the considered star is

ϕΣ =

√GM

2R

(1− r2

R2

)+

Ω2

√Gr2(3cos2θ − 1) (8.18)

Since the electric potential must be equal to zero on the surface of the star,at r = a and r = c

ϕΣ = 0 (8.19)

and we obtain the equation which describes the equilibrium form of the core

of a rotating star (at a2−c2

a2 ≪ 1)

a2 − c2

a2≈ 9

Ω2

Gγ. (8.20)

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52 CHAPTER 8. THE APSIDAL ROTATION

8.3 The angular velocity of the apsidal rotation

Taking into account of Eq.(8.20) we have

ω

Ω≈ 27

20π

Ω2

Gγ(8.21)

If both stars of a close pair induce a rotation of periastron, this equation trans-forms to

ω

Ω≈ 27

20π

Ω2

G

(1

γ1+

1

γ2

), (8.22)

where γ1 and γ2 are densities of star cores.The equilibrium density of star cores is known (Eq.(2.18)):

γ =16

9π2

A

Zmp

(Z + 1)3

a3B. (8.23)

If we introduce the period of ellipsoidal rotation P = 2πΩ and the period of

the rotation of periastron U = 2πω , we obtain from Eq.(8.21)

PU

(PT

)2

≈2∑

1

ξi, (8.24)

where

T =

√243 π3

80τ0 ≈ 10τ0, (8.25)

τ0 =

√a3BG mp

≈ 7.7 · 102sec (8.26)

and

ξi =Zi

Ai(Zi + 1)3. (8.27)

8.4 The comparison of the calculated angularvelocity of the periastron rotation with ob-servations

Because the substance density (Eq.(8.23)) is depending approximately on thesecond power of the nuclear charge, the periastron movement of stars consistingof heavy elements will fall out from the observation as it is very slow. Practicallythe obtained equation (8.24) shows that it is possible to observe the periastronrotation of a star consisting of light elements only.

The value ξ = Z/[A(Z + 1)3] is equal to 1/8 for hydrogen, 0.0625 for deu-terium, 1.85 · 10−2 for helium. The resulting value of the periastron rotation of

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8.4. THE COMPARISON WITH OBSERVATIONS 53

double stars will be the sum of separate stars rotation. The possible combina-tions of a couple and their value of

∑21 ξi for stars consisting of light elements

is shown in Table 8.4.

star1 star2 ξ1 + ξ2composed of composed of

H H .25H D 0.1875H He 0.143H hn 0.125D D 0.125D He 0.0815D hn 0.0625He He 0.037He hn 0.0185

Table 8.4

The ”hn” notation in Table 8.4 indicates that the second component of thecouple consists of heavy elements or it is a dwarf.

The results of measuring of main parameters for close binary stars are gath-ered in [8]. For reader convenience, the data of these measurement is applied inthe Table in Appendix. One can compare our calculations with data of thesemeasurements. The distribution of close binary stars on value of (P/U)(P/T )2

is shown in Fig.8.1 on logarithmic scale. The lines mark the values of parame-ters

∑21 ξi for different light atoms in accordance with 8.27. It can be seen that

calculated values the periastron rotation for stars composed by light elementswhich is summarized in Table8.4 are in good agreement with separate peaks ofmeasured data. It confirms that our approach to interpretation of this effect isadequate to produce a satisfactory accuracy of estimations.

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54 CHAPTER 8. THE APSIDAL ROTATION

-3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5

-3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5

0

2

4

6

8

10

12

0

2

4

6

8

10

12

N He+

He

D+

He

H+

He

H+

D

H+

H

H ;

D+

DDHe

log[(P/U)(P/T)2]

log(ξ1+ξ2)

Figure 8.1: The distribution of close binary stars [8] on value of (P/U)(P/T )2.

Lines show parameters∑2

1 ξi for different light atoms in according with 8.27.

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Chapter 9

The solar seismicaloscillations

9.1 The spectrum of solar seismic oscillations

The measurements [6] show that the Sun surface is subjected to a seismic vi-bration. The most intensive oscillations have the period about five minutes andthe wave length about 104km or about hundredth part of the Sun radius. Theirspectrum obtained by BISON collaboration is shown in Fig.9.1.

It is supposed, that these oscillations are a superposition of a big number ofdifferent modes of resonant acoustic vibrations, and that acoustic waves prop-agate in different trajectories in the interior of the Sun and they have multiplereflection from surface. With these reflections trajectories of same waves can beclosed and as a result standing waves are forming.

Specific features of spherical body oscillations are described by the expansionin series on spherical functions. These oscillations can have a different numberof wave lengths on the radius of a sphere (n) and a different number of wavelengths on its surface which is determined by the l-th spherical harmonic. It isaccepted to describe the sunny surface oscillation spectrum as the expansion inseries [5]:

νnlm ≃ ∆ν0(n+l

2+ ǫ0)− l(l + 1)D0 +m∆νrot. (9.1)

Where the last item is describing the effect of the Sun rotation and is small.The main contribution is given by the first item which creates a large splittingin the spectrum (Fig.9.1)

ν = νn+1,l − νn,l. (9.2)

The small splitting of spectrum (Fig.9.1) depends on the difference

δνl = νn,l − νn−1,l+2 ≈ (4l + 6)D0. (9.3)

A satisfactory agreement of these estimations and measurement data can beobtained at [5]

55

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56 CHAPTER 9. THE SOLAR SEISMICAL OSCILLATIONS

Figure 9.1: (a) The power spectrum of solar oscillation obtained by means ofDoppler velocity measurement in light integrated over the solar disk. The datawere obtained from the BISON network [6]. (b) An expanded view of a part offrequency range.

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9.1. THE SPECTRUM OF SOLAR OSCILLATIONS 57

∆ν0 = 120 µHz, ǫ0 = 1.2, D0 = 1.5 µHz, ∆νrot = 1µHz. (9.4)

To obtain these values of parameters ∆ν0, ǫ0 D0 from theoretical models isnot possible. There are a lot of qualitative and quantitative assumptions used ata model construction and a direct calculation of spectral frequencies transformsinto a unresolved complicated problem.

Thus, the current interpretation of the measuring spectrum by the sphericalharmonic analysis does not make it clear. It gives no hint to an answer to thequestion: why oscillations close to hundredth harmonics are really excited andthere are no waves near fundamental harmonic?

The measured spectra have a very high resolution (see Fig.(9.1)). It meansthat an oscillating system has high quality. At this condition, the system musthave oscillation on a fundamental frequency. Some peculiar mechanism mustexist to force a system to oscillate on a high harmonic. The current explanationdoes not clarify it.

It is important, that now the solar oscillations are measured by means of twodifferent methods. The solar oscillation spectra which was obtained on program”BISON”, is shown on Fig.(9.1)). It has a very high resolution, but (accordinglyto the Liouville’s theorem) it was obtained with some loss of luminosity, and asa result not all lines are well statistically worked.

Another spectrum was obtained in the program ”SOHO/GOLF”. Con-versely, it is not characterized by high resolution, instead it gives informationabout general character of the solar oscillation spectrum (Fig.9.2)).

The existence of this spectrum requires to change the view at all problemsof solar oscillations. The theoretical explanation of this spectrum must giveanswers at least to four questions :

1.Why does the whole spectrum consist from a large number of equidistantspectral lines?

2.Why does the central frequency of this spectrum F is approximately equalto ≈ 3.23 mHz?

3. Why does this spectrum splitting f is approximately equal to 67.5 µHz?4. Why does the intensity of spectral lines decrease from the central line to

the periphery?The answers to these questions can be obtained if we take into account

electric polarization of a solar core.The description of measured spectra by means of spherical analysis does not

make clear of the physical meaning of this procedure. The reason of difficultieslies in attempt to consider the oscillations of a Sun as a whole. At existingdividing of a star into core and atmosphere, it is easy to understand that thecore oscillation must form a measured spectrum. The fundamental mode ofthis oscillation must be determined by its spherical mode when the Sun radiusoscillates without changing of the spherical form of the core. It gives a mostlow-lying mode with frequency:

Ωs ≈csR⋆, (9.5)

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58 CHAPTER 9. THE SOLAR SEISMICAL OSCILLATIONS

Figure 9.2: (a) The measured power spectrum of solar oscillation. The datawere obtained from the SOHO/GOLF measurement [16]. (b) The calculatedspectrum described by Eq.(9.26) at Z = 2 and A/Z = 5.

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9.2. THE SOUND SPEED IN PLASMA 59

where cs is sound velocity in the core.

It is not difficult to obtain the numerical estimation of this frequency by orderof magnitude. Supposing that the sound velocity in dense matter is 107cm/cand radius is close to 1

10 of external radius of a star, i.e. about 1010cm, one canobtain as a result

F =Ωs2π

≈ 10−3Hz (9.6)

It gives possibility to conclude that this estimation is in agreement with mea-sured frequencies. Let us consider this mechanism in more detail.

9.2 The sound speed in hot plasma

The pressure of high temperature plasma is a sum of the plasma pressure (idealgas pressure) and the pressure of black radiation:

P = nekT +π2

45~3c3(kT )4. (9.7)

and its entropy is

S =1

AZmp

ln(kT )3/2

ne+

4π2

45~3c3ne(kT )3, (9.8)

The sound speed cs can be expressed by Jacobian [9]:

c2s =D(P, S)

D(ρ, S)=

(D(P,S)D(ne,T )

)

(D(ρ,S)D(ne,T )

) (9.9)

or

cs =

5

3

kT

A/Zmp

[1 +

2(

4π2

45~3c3

)2(kT )6

5ne[ne +8π2

45~3c3 (kT )3]

]1/2

(9.10)

For T = T⋆ and ne = n⋆ we have:

4π2(kT⋆)3

45~3c3n⋆=≈ 0.58 . (9.11)

Finally we obtain:

cs =

5

3

T⋆

(A/Z)mp[1.085]

)1/2

≈ 5.63 107(Z + 1

A/Z

)1/2

cm/s . (9.12)

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60 CHAPTER 9. THE SOLAR SEISMICAL OSCILLATIONS

9.3 The basic elastic oscillation of a spherical

core

Star cores consist of dense high temperature plasma which is a compressiblematter. The basic mode of elastic vibrations of a spherical core is related withits radius oscillation. For the description of this type of oscillation, the potentialφ of displacement velocities vr =

∂ψ∂r can be introduced and the motion equation

can be reduced to the wave equation expressed through φ [9]:

c2s∆φ = φ, (9.13)

and a spherical derivative for periodical in time oscillations (∼ e−iΩst) is:

∆φ =1

r2∂

∂r

(r2∂φ

∂r

)= −Ω2

s

c2sφ . (9.14)

It has the finite solution for the full core volume including its center

φ =A

rsin

Ωsr

cs, (9.15)

where A is a constant. For small oscillations, when displacements on the surfaceuR are small (uR/R = vR/ΩsR → 0) we obtain the equation:

tgΩsR

cs=

ΩsR

cs(9.16)

which has the solution:ΩsR

cs≈ 4.49. (9.17)

Taking into account Eq.(9.12)), the main frequency of the core radial elasticoscillation is

Ωs = 4.49

10.85

(3/2)7π

[Gmp

r3B

]A

Z

(Z + 1

)31/2

. (9.18)

It can be seen that this frequency depends on Z and A/Z only.Some values of frequencies of radial sound oscillations F = Ωs/2π calculated

from this equation for selected A/Z at Z = 1 and Z = 2 are shown in thirdcolumn of Table (9.3).

Table(9.3).

F ,mHz F ,mHzZ A/Z (calculated star

on Eq.(9.18)) measured1 1 0.79 η Bootis 0.85

The Procion(Aα CMi) 1.041 2 1.11

β Hydri 1.082 2 2.032 3 2.48 α Cen A 2.372 4 2.872 5 3.24 The Sun 3.23

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9.4. THE LOW FREQUENCY OSCILLATION 61

The measured frequencies of surface vibrations for some stars [5] are shownin right part of this table. The data for ν Indus and ξ Hydrae also exist[5], but characteristic frequencies of these stars are below 0.3 mHz and theyhave some other mechanism of excitation, probably. One can conclude from thedata of Table 1 that the core of the Sun is basically composed by helium-10.It is not a confusing conclusion, because the plasma electron gas prevents thedecay of β-active nuclei (see Sec.11). This mechanism can probably to stabilizeneutron-excess nuclei.

9.4 The low frequency oscillation of the density

of a neutral plasma

Hot plasma has the density n⋆ at its equilibrium state. The local deviationsfrom this state induce processes of density oscillation since plasma tends toreturn to its steady-state density. If we consider small periodic oscillations ofcore radius

R = R+ uR · sin ωn⋆t, (9.19)

where a radial displacement of plasma particles is small (uR ≪ R), the oscilla-tion process of plasma density can be described by the equation

dEdR

= MR . (9.20)

Taking into accountdEdR

=dEplasmadne

dnedR

(9.21)

and3

8π3/2

Nee3a

3/20

(kT)1/2n⋆R2

= Mω2n⋆

(9.22)

From this we obtain

ω2n⋆

=3

π1/2kT

(e2

aBkT

)3/2(1 + Z)3

R2A/Zmp(9.23)

and finally

ωn⋆=

28

35π1/2

101/2α3/2

[Gmp

a3B

]A

Z

[Z + 1

]4.51/2

, (9.24)

where α = e2

~c is the fine structure constant. These low frequency oscillations ofneutral plasma density are similar to phonons in solid bodies. At that oscilla-tions with multiple frequencies kωn⋆

can exist. Their power is proportional to1/κ, as the occupancy these levels in energy spectrum must be reversely pro-portional to their energy k~ωn⋆

. As result, low frequency oscillations of plasma

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62 CHAPTER 9. THE SOLAR SEISMICAL OSCILLATIONS

density constitute set of vibrations

κ=1

1

κsin(κωn⋆

t) . (9.25)

9.5 The spectrum of solar core oscillations

The set of the low frequency oscillations with ωη can be induced by soundoscillations with Ωs. At that, displacements obtain the spectrum:

uR ∼ sin Ωst ·∑

κ=0

1

κsin κωn⋆

t· ∼ ξ sin Ωst+∑

κ=1

1

κsin (Ωs ± κωn⋆

)t, (9.26)

where ξ is a coefficient ≈ 1.This spectrum is shown in Fig.(9.2).The central frequency of experimentally measured distribution of solar os-

cillations is approximately equal to (Fig.(9.1))

F⊙ ≈ 3.23 mHz (9.27)

and the experimentally measured frequency splitting in this spectrum is approx-imately equal to

f⊙ ≈ 68 µHz. (9.28)

A good agreement of the calculated frequencies of basic modes of oscillations(from Eq.(9.18) and Eq.(8.4)) with measurement can be obtained at Z = 2 andA/Z = 5:

FZ=2;A

Z=5

=Ωs2π

= 3.24 mHz; fZ=2;A

Z=5

=ωn⋆

2π= 68.1 µHz. (9.29)

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Chapter 10

Addendum I: The energygeneration and the time oflife of the Sun

Now it is commonly accepted to think that the energy generation in stars isbasically caused by thermonuclear reactions of hydrogen-helium cycles. It seemsto be valid for heavy stars consisting of hydrogen and helium at ratio A/Z =1 ÷ 2. In this part of the star mass spectrum (Fig.5.1), sharp lines are absent(beside one related to He-3, probably). This part of spectrum is rather smeared.But this conception is in contradiction with the fact of an existence of the linedspectrum mass of stars with A/Z > 3. Reaction of this type must go witha change of relation A/Z of a nuclear fuel and ”smearing” of narrow peaksof the spectrum of star masses during milliards of years. It seems that it ispossible to make agreement of the measured lined spectrum of these stars andthermonuclear mechanism of reaction, if we suppose that a basic thermonuclearreaction is

AZX + A

ZX = 2A2ZX + γ (10.1)

i.e., for example, two nuclei of tritium join up into a helium-6 nucleus:

31H + 3

1H = 62He+ γ (10.2)

For Sun, a process of nuclear fusion of two nuclei of hydrogen 51H joining into

helium 102 He must be prevailing:

51H + 5

1H = 102 He+ γ (10.3)

The mass of nucleus hydrogen 51H is equal approximately to 5.03954 a.m.u., the

mass of helium 102 He is equal approximately to 10.0524 ... Thus, the energy

about 4 ·10−5 erg will be emitted in a single reaction. The full number of nucleiin the star core:

N⋆ =M⋆

AZmp

≈ 1056. (10.4)

63

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64 CHAPTER 10. ADDENDUM I: THE ENERGY GENERATION

Now the Sun radiates from its surface 3.86 · 1033 erg/s. Approximately 1038

reactions during one second can provide for this energy. The question emerges:how much hydrogen is there stored into the Sun now?

The answer can be obtained from the analysis of the solar oscillation frequen-cies. These measurements give two frequencies. Their theoretical dependencieson chemical parameters A/Z and Z are known from Eqs.(9.18) and (9.4). Usingthese equations, it is possible to express these two chemical parameters:

〈A/Z〉 = 2.33 · 10−4π6α3a3BGmp

(F3

f2

)2

, (10.5)

〈Z〉 = 11.14

πα

(f

F

)4/3

− 1. (10.6)

The substitution of numerical values gives

〈A/Z〉⊙ = 5.04 . (10.7)

and〈Z〉⊙ = 1.85 (10.8)

The last equation speaks that now the Sun must consist approximately from85% of 10

2 He and 15% of 51H .

Experts think that approximately for the last 5 milliard years the Sun wasshining more or less monotone without catastrophic jumps of radiation.

It is not difficult to estimate, that stockpiles of nuclear fuel 51H at a present

speed burning must be enough to the Sun for several milliard years ahead.This consideration extremely radically ”solves” the problem of the solar neu-

trino deficiency. Reactions considered above yield no neutrinos at all. In thisconnection, the question emerges: is it possible to agree the considered mech-anism based on the form of stellar mass spectrum with the measured flux ofneutrinos?

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Chapter 11

Addendum II: Amechanism of stabilizationfor neutron-excess nuclei inplasma

11.1 β-active isotopes of hydrogen and helium

The form of the star mass spectrum (Fig.(5.1)) indicates that plasma of manystars consists of neutron-excess nuclei with A/Z = 3, 4, 5 and so on. Thesenuclei are subjects of the β-decay under the ”terrestrial” conditions. Hydrogenisotopes 4

1H,51H,

61H have short time of life and emit electrons with energy more

than 20 Mev under the ”terrestrial” conditions. The decay of helium isotopes62He,

82He,

102 He produces electrons with the energy of almost the same level,

but the time of life can reach tenth part of the seconds.

Stars have the time of life about billions years and the linear spectrum oftheir masses is conserved. Thus we should suppose that there is some mechanismof stabilization of β-radioactive nuclei inside stars. One similar mechanism iswell known - it is neutronization [9]§106. This mechanism is characteristic fordwarfs with density of particles about 1030 per cm3. But this mechanism is notapplicable to hot stars where densities are much below than this value.

11.2 The electron cloud of plasma cell

Let us consider a possible mechanism of the action of the electron gas effecton the plasma nuclear subsystem. It is accepted to consider dense plasma tobe divided in plasma cells. These cells are filled by electron gas and they havepositively charged nuclei in their centers [12].

65

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66CHAPTER 11. ADDENDUM II: A MECHANISM OF STABILIZATION FOR NEUTRON-EXCESSNUCLEI IN PLASMA

This construction is non stable from the point of view of the classical me-chanics because the unlike charge collapse is ”thermodynamic favorable”. Toavoid a divergence in the theoretical description of this problem, one can artifi-cially cut off the integrating at some small distance characterizing the particlesinteraction. For example, nuclei can be considered as hard cores with the finiteradii.

It is more correctly, to consider this structure as a quantum-mechanicalobject and to suppose that the electron can not approach the nucleus closerthan its own de Broglie radius λe.

Far from the center of the plasma cell on its periphery, the kinetic energyof the electron is approximately equal to kT . The same level has its potentialenergy. We can neglect them for simplicity and to write:

Ekin = Epot = 0. (11.1)

These energies will be large if the electron ”approaches” the nucleus at a distanceless by the Compton radius:

r ≪ ~

mec. (11.2)

Where its momentum will be ultra-relativistic p ≫ mec. At the same time thefull energy of the electron must be conserved:

Ekin + Epot = 0. (11.3)

The potential energy of an electron moving in an electrical field of a nucleuscan be estimated on the base of the Lorentz transformation of fields [11]§24. Ifin a laboratory frame where the nucleus is placed, it creates an electric potentialϕ0, in a frame moving with velocity v in relation to the laboratory frame thepotential is equal:

ϕ =ϕ0√1− v2

c2

. (11.4)

and in the ultra-relativistic case, potential energy of an electron in the electricfield of a nucleus (the nucleus of hydrogen with Z = 1, for simplicity) can bewritten:

Epot ≃ − e2

λex. (11.5)

Where the following notation is introduced:

x ≡ p

mec. (11.6)

Near a nucleus x≫ 1. Besides, the kinetic energy of relativistic electron:

Ekin = cp = xmec2. (11.7)

The balance of energies according to Eq.(11.3) exists at

λe ≃ α~

mec. (11.8)

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11.2. THE ELECTRON CLOUD OF PLASMA CELL 67

Where

α ≡ e2

~c≈ 1

137(11.9)

is the fine structure constant.So the clot of the electron cloud gathers around the nucleus at the distance

λe and it is characterized by the energy

Epot ≃mec

2

α≈ 70Mev, (11.10)

(it is much more than the energy which is characteristic for the electron cloudon the periphery of a plasma cell, which was neglected correctly).

The this situation, the dense clot of the electron cloud gathers around thenucleus prevents its decay in the event that the outgoing β-electron has lowerenergy. Of course, this barrier can be penetrated with the tunneling of anelectron. The nuclei have more chances to decay if they emit electrons withhigher energies. Evidently, it can explain the fact of the decreasing of thenumber of stars at the increasing of the ratio A/Z from A/Z ≈ 4 in the spectrum(Fig.(5.1))) and the fact of its falling to zero at A/Z ≈ 10, where possibly theenergy of the outgoing electron approaches to the level of Eq.(11.10).

It is interesting, is it possible to study this effect under laboratory conditions?One can use gaseous tritium for it and can measure the rate of its decay at twostates. First the rate of tritium decay at atomic (molecular) state. Second, thesame rate under the effect of ionizing electric discharge. Essentially, one mustaim to use the dense gas and the power discharge in order to ionize more atomsof tritium. Taking into account the preceding consideration, such a test doesnot look as a hopeless project.

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68CHAPTER 11. ADDENDUM II: A MECHANISM OF STABILIZATION FOR NEUTRON-EXCESSNUCLEI IN PLASMA

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Chapter 12

Addendum III: Other stars,their classification and somecosmology

The Schwarzsprung-Rassel diagram is now a generally accepted base for starclassification. It seems that a classification based on the EOS of substancemay be more justified from physical point of view. It can be emphasized bypossibility to determine the number of classes of celestial bodies.

The matter can totally have seven statesThe atomic substance at low temperature exists as condensed matter (solid

or liquid). At high temperature it transforms into gas phase.The electron -nuclear plasma can exist in four states. It can be relativistic or

non-relativistic. The electron gas of non-relativistic plasma can be degenerate(cold) or non-degenerate (hot). If electron gas of plasma is relativistic, its nu-clear subsystem may be cold at low temperature. At very high temperature, theenergy of nuclear subsystem can exceed the energy of degeneration of relativisticelectrons.

In addition to that a substance can exist as neutron matter with nucleardensity in degenerate state.

At present, assumptions about existence of matter at different states, otherthan the above-named, seem unfounded. Thus, seven possible states of mattershow a possibility of classification of celestial bodies in accordance with thisdividing.

12.1 The atomic substance

12.1.1 Small bodies

Small celestial bodies - asteroids and satellites of planets - are usually consideredas bodies consisting from atomic matter.

69

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70 CHAPTER 12. ADDENDUM III: OTHER STARS

12.1.2 Giants

The transformation of atomic matter into plasma can be induced by action ofhigh pressure, high temperature or both these factors. If these factors inside abody are not high enough, atomic substance can transform into gas state. Thecharacteristic property of this celestial body is absence of electric polarizationinside it. If temperature of a body is below ionization temperature of atomicsubstance but higher than its evaporation temperature, the equilibrium equationcomes to

− dP

dr=Gγ

r2Mr ≈

P

R≈ γ

mp

kT

R. (12.1)

Thus, the radius of the body

R ≈ GMmp

kT. (12.2)

If its mass M ≈ 1033 g and temperature at its center T ≈ 105 K, its radius isR ≈ 102 R⊙. These proporties are characteristic for giants, where pressure atcenter is about P ≈ 1010 din/cm2 and it is not enough for substance ionization.

12.2 Plasmas

12.2.1 The non-relativistic non-degenerate plasma. Stars.

Characteristic properties of hot stars consisting of non-relativistic non-degenerate plasma was considered above in detail. Its EOS is ideal gas equation.

12.2.2 Non-relativistic degenerate plasma. Planets.

At cores of large planets, pressures are large enough to transform their substanceinto plasma. As temperatures are not very high here, it can be supposed, thatthis plasma can degenerate:

T << TF (12.3)

The pressure which is induced by gravitation must be balanced by pressure ofnon-relativistic degenerate electron gas

GM2

6RV≈ (3π2)2/3

5

~2

me

mpA/Z

)5/3

(12.4)

It opens a way to estimate the mass of this body:

M ≈ MCh

(~

mc

)3/2(γ

mp

)1/263/29π

4(A/Z)5/2(12.5)

At density about γ ≈ 1 g/cm3, which is characteristic for large planets, weobtain their masses

M ≈ 10−3 MCh

(A/Z)5/2≈ 4 · 1030

(A/Z)5/2g (12.6)

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12.2. PLASMAS 71

Thus, if we suppose that large planets consist of hydrogen (A/Z=1), their massesmust not be over 4·1030g. It is in agreement with the Jupiter’s mass, the biggestplanet of the Sun system.

12.2.3 The cold relativistic substance

An energy of a relativistic fermi-system with volume V can be obtained fromthe general expression [9]:

E =V c

π2~3

∫ pF

0

p2√m2c2 + p2dp. (12.7)

At integrating of this expression after subtracting of self-energy of particles, weobtain the kinetic energy of N relativistic particles:

Ekinetic = 3

8Nmc2

[x(2x2 + 1)

√x2 + 1−Arcsinh(x) − 8

3x3

x3

](12.8)

where x = pFmc and density of substance:

n =p3F

3π2~3=

x3

3π2

(mc~

)3. (12.9)

The pressure of this system is

P = −(dEkineticdV

)

S=0

=mc2

8π2

(mc~

)3 [x

(2

3x2 − 1

)√x2 + 1 +Arcsinh(x)

]

(12.10)For simplicity we can suppose that main part of mass of relativistic star isconcentrated into its core and it is uniformly distributed here. In this case wecan write the pressure balance equation:

GM2

2R= 3PV. (12.11)

It permits to estimate the full number of particles into the considered system:

N =

(~c

Gm2p

)3/2(3

)21

π3/2

[x(23x

2 − 1)√

x2 + 1 +Arcsinh(x)

x4

]3/2.

(12.12)Accordingly to the virial theorem:

Etotal = −Ekinetic (12.13)

and (12.8), the full energy of a relativistic star

Etotal ∼ − 1

x9

[x(2x2 + 1)

√x2 + 1−Arcsinh(x) − 8

3x3]·

·[x

(2

3x2 − 1

)√x2 + 1 +Arcsinh(x)

]3/2. (12.14)

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72 CHAPTER 12. ADDENDUM III: OTHER STARS

Because this expression has a minimum at x ≈ 1.35, a star consisting of rela-tivistic substance must have the equilibrium particle density:

n⋆ ≈ 8.3 · 10−2(mc

~

)3. (12.15)

The relativistic degenerate plasma. Dwarfs.

The degenerate relativistic plasma has a cold relativistic electron subsystem.Its nuclear subsystem can be non-relativistic. The star consisting of this plasmaaccordingly to Eq.(12.15) atm = me, must have an energy minimum at electrondensity n⋆ ≈ 1.4 · 1030 particle/cm3 at a star radius

R ≈ 10−2R⊙ (12.16)

It is not difficult to see that these densities and radii are characteristic for dwarfs.

The neutron matter. Pulsars.

Dwarfs may be considered as stars where a process of neutronization is justbeginning. At a nuclear density, plasma turns into neutron matter. 1

In accordance with Eq.(12.15) at m = mn, a star consisting of neutron mat-ter must have the minimal energy at neutron density n⋆ ≈ 9 ·1039 particle/cm3.As result the masses of neutron stars must be approximately equal toMCh. Themeasured mass distribution of pulsar composing binary stars [17] is shown onFig.12.1. It can be considered as a confirmation of the last conclusion.

12.2.4 The hot relativistic plasma.Quasars?

Plasma is hot if its temperature is higher than degeneration temperature ofits electron gas. The ratio of plasma temperature in the core of a star to thetemperature of degradation of its electron gas for case of non-relativistic hotstar plasma is (Eq.(2.23))

T⋆

TF (n⋆)≈ 40 (12.17)

it can be supposed that the same ratio must be characteristic for the case of arelativistic hot star. At this temperature, the radiation pressure plays a mainrole and accordingly the equation of the pressure balance takes the form:

GM2

6RV≈ π2

45

(kT⋆)4

(~c)3≈(T⋆

TF

)3

kTn (12.18)

This makes it possible to estimate the mass of a hot relativistic star

M ≈(T⋆TF

)6(~c

Gm2p

)3/2

mp ≈ 109M⊙ (12.19)

1At nuclear density neutrons and protons are indistinguishable inside pulsars as inside ahuge nucleus. It permits to suppose a possibility of gravity induced electric polarization inthis matter.

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12.2. PLASMAS 73

1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Mpulsar/Mo

0

1

2

3

4

5

6

7

8

9

10N

Figure 12.1: The mass distribution of pulsars from binary systems [17].On ab-scissa the logarithm of pulsar mass in solar mass is shown.

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74 CHAPTER 12. ADDENDUM III: OTHER STARS

6 7 8 9 10 11 12 13 14log M/Mo

0

1

2

3

4

5

6

7

8

9

10

N

Figure 12.2: The mass distribution of galaxies. [1]. On the abscissa, the loga-rithm of the galaxy mass over the Sun mass is shown.

According to the existing knowledge, among compact celestial objects onlyquasars have masses of this level. Apparently it is an agreed-upon opinionthat quasars represent some relatively short stage of evolution of galaxies. If weadhere to this hypothesis, the lack of information about quasar mass distribu-tion can be replaced by the distribution of masses of galaxies [1](Fig.12.2). Itcan be seen, that this distribution is in a qualitative agreement with suppositionthat quasars are composed from the relativistic hot plasma.

12.3 Some cosmology

Thus, it seems possible under some assumptions to find characteristic parame-ters of different classes of stars, if to proceed from EOS of atomic, plasma andneutron substances. Seven EOS can be compared with seven classes of celestialbodies. As any other EOS are unknown, it gives a reason to think that allclasses of celestial bodies are discovered. With the exception of ,probably, onebody that could have existed in the past. The neutron matter at density oforder 1040particle/cm3 (in accordance with Eq.(12.15)) is not ultra-relativisticmatter and its energy and pressure must depend on temperature.2 It seems,there is no thermodynamical prohibition to imagine this matter so hot when

2The ultra-relativistic matter with pF ≫ mc is possessed by limiting pressure which is notdepending on temperature.

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12.3. SOME COSMOLOGY 75

the black radiation pressure will dominate inside it. An estimation shows thatit can be possible if mass of this body is near to 1050g or even to 1055g. As itis accepted to think that full mass of the Universe is about 1053g, it can be as-sumed that on an early stage of development of Universe, there was some bodywith a mass about 1053g composed by the neutron matter at nuclear densitywith the radiation at temperature above 1012K. After some time, with tem-perature decreased it has lost its stability and decayed into quasars with massup to 1012MCh, consisting of a relativistic plasma with hot nuclear componentat T > 1010K. After next cooling at loosing of stability they was decaying ongalaxies of hot stars with mass about M ≈ MCh and core temperature aboutT ≈ 107K, composed by non-relativistic hot plasma. A next cooling must leadshot stars to decaying on dwarfs, pulsars, planets or may be on small bodies.The substances of these bodies (in their cores) consists of degenerate plasma(degenerate electron subsystem and cold nuclear subsystem) or cold neutronmatter, it makes them stable in expanding and cooling Universe.3

3The temperature of plasma inside these bodies can be really quite high as electron gasinto dwarfs, for example, will be degenerate even at temperature T ≈ 109K.

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76 CHAPTER 12. ADDENDUM III: OTHER STARS

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Chapter 13

The conclusion

Evidently, the main conclusion from the above consideration consists in state-ment of the fact that now there are quite enough measuring data to place thetheoretical astrophysics on a reliable foundation. All above measuring data areknown for a relatively long time. The traditional system of view based on theEuler equation in the form (1.1) could not give a possibility to explain and evento consider. with due proper attention, to these data. Taking into account thegravity induced electric polarization of plasma and a change starting postulategives a possibility to obtain results for explanation of measuring data consideredabove.

Basically these results are the following.

Using the standard method of plasma description leads to the conclusionthat at conditions characteristic for the central stellar region, the plasma hasthe minimum energy at constant density n⋆ (Eq.(2.18)) and at the constanttemperature T⋆ (Eq.(5.21)).

This plasma forms the core of a star, where the pressure is constant andgravity action is balanced by the force of the gravity induced by the electricpolarization. The virial theorem gives a possibility to calculate the stellar coremass M⋆ (Eq.(5.25)) and its radius R⋆ (5.27). At that the stellar core volumeis approximately equal to 1/1000 part of full volume of a star.

The remaining mass of a star located over the core has a density approxi-mately thousand times smaller and it is convenient to name it a star atmosphere.At using thermodynamical arguments, it is possible to obtain the radial depen-dence of plasma density inside the atmosphere na ≈ r−6 (Eq.(4.17)) and theradial dependence of its temperature Ta ≈ r−4 (Eq.(4.18)).

It gives a possibility to conclude that the mass of the stellar atmosphereMa (Eq.(4.19)) is almost exactly equal to the stellar core mass.Thus, the full

77

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78 CHAPTER 13. THE CONCLUSION

stellar mass can be calculated. It depends on the ratio of the mass and thecharge of nuclei composing the plasma. This claim is in a good agreement withthe measuring data of the mass distribution of both - binary stars and closebinary stars (Fig.(5.1)-(5.2)) 1. At that it is important that the upper limit ofmasses of both - binary stars and close binary stars - is in accordance with thecalculated value of the mass of the hydrogen star (Eq.(5.26)). The obtainedformula explains the origin of sharp peaks of stellar mass distribution - theyevidence that the substance of these stars have a certain value of the ratio A/Z.In particular the solar plasma according to (Eq.(5.26)) consists of nuclei withA/Z = 5.

Knowing temperature and substance density on the core and knowning theirradial dependencies, it is possible to estimate the surface temperature T0 (5.38)and the radius of a star R0 (5.37). It turns out that these measured parametersmust be related to the star mass with the ratio T0R0 ∼ M

5/4 (5.49). It is in agood agreement with measuring data (Fig.(5.3)).

Using another thermodynamical relation - the Poisson’s adiabat - gives away to determine the relation between radii of stars and their masses R3

0 ∼ M2

(Eq.(6.16)), and between their surface temperatures and masses T0 ∼ M5/7

(Eq.(6.19)). It gives the quantitative explanation of the mass-luminosity depen-dence (Fig.(6.3)).

According to another familiar Blackett’s dependence, the giromagnetic ratiosof celestial bodies are approximately equal to

√G/c. It has a simple explanation

too. When there is the gravity induced electric polarization of a substance of acelestial body, its rotation must induce a magnetic field (Fig.(7.1)). It is impor-tant that all (composed by eN-plasma) celestial bodies - planets, stars, pulsars- obey the Blackett’s dependence. It confirms a consideration that the gravityinduced electric polarization must be characterizing for all kind of plasma. Thecalculation of magnetic fields of hot stars shows that they must be proportionalto rotation velocity of stars (7.10). Magnetic fields of Ap-stars are measured,and they can be compared with periods of changing of luminosity of these stars.It is possible that this mechanism is characteristic for stars with rapid rotation(Fig.(7.2)), but obviously there are other unaccounted factors.

Taking into account the gravity induced electric polarization and comingfrom the Clairault’s theory, we can describe the periastron rotation of binarystars as effect descended from non-spherical forms of star cores. It gives thequantitative explanation of this effect, which is in a good agreement with mea-suring data (Fig.(8.1)).

The solar oscillations can be considered as elastic vibrations of the solarcore. It permits to obtain two basic frequencies of this oscillation: the basic

1The measurement of parameters of these stars has a satisfactory accuracy only.

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79

frequency of sound radial oscillation of the core and the frequency of splittingdepending on oscillations of substance density near its equilibrium value. Itshows a good agreement with the measuring data and demonstrates that theSun consists generally of helium-10 (Fig.(9.2)).

A calculation can be carried out in reverse direction. Two measured fre-quencies of solar oscillations allow to calculate the chemical composition of solarsubstance. It must be composed by 85% of helium-10 and by 15% of hydrogen-5. It shows that the process of quiet burning of the Sum will be continue for afew milliards years ahead.

The plasma can exists in four possible states. The non-relativistic electrongas of plasma can be degenerate and non-degenerate. Plasma with relativis-tic electron gas can have a cold and a hot nuclear subsystem. Together withthe atomic substance and neutron substance, it gives seven possible states. Itsuggests a way of a possible classification of celestial bodies. The advantage ofthis method of classification is in the possibility to estimate theoretically mainparameters characterizing the celestial bodies of each class. And these predictedparameters are in agreement with astronomical observations. It can be supposedhypothetically that cosmologic transitions between these classes go in directionof their temperature being lowered. But these suppositions have no formal baseat all.

Discussing formulas obtained, which describe star properties, one can notea important moment: these considerations permit to look at this problem fromdifferent points of view. On the one hand, the series of conclusions follows fromexistence of spectrum of star mass (Fig.(5.1)) and from known chemical compo-sition dependence. On the another hand, the calculation of natural frequenciesof the solar core gives a different approach to a problem of chemical compositiondetermination. It is important that for the Sun, both these approaches lead tothe same conclusion independently and unambiguously. It gives a confidence inreliability of obtained results.

In fact, the calculation of magnetic fields of hot stars only does not givea satisfactory explanation of existing measuring data. At that it is unlikelythat the reason of discrepancy is in the use of dubious suggestions - the dipolemagnetic field of the Sun is not explained too. But it is important, that the allremaining measuring data (all known of today) confirm both - the new postulateand formulas based on it. At that, the main stellar parameters - masses, radiiand temperatures - are expressed through combinations of world constants andat that they show a good accordance with observation data. It is important thatquite a satisfactory quantitative agreement of obtained results and measuringdata can be achieved by simple and clear physical methods without use of anyfitting parameter. It gives a special charm and attractiveness to star physics.

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80 Bibliography

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Bibliography

[1] Allen C.W. - Astrophysical quantities, 1955,University of London, TheAthlone Press.

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82 BIBLIOGRAPHY

Astrophysical Observatory of Russian Academy of Sciences, September 24-27, 1999), eds: Yu. V. Glagolevskij and I.I. Romanyuk, Moscow, 2000, pp.18-50.

[14] Russel H.N.: Monthly Notices of the RAS 88, 642, (1928)

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[16] Solar Physics, 175/2, (http://sohowww.nascom.nasa.gov/gallery/Helioseismology)

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Chapter 14

Appendix

The Table of main parameters of close binary stars (cited onKh.F.Khaliullin’s dissertation, Sternberg Astronomical Institute. In Russian)

83

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84 CHAPTER 14. APPENDIX

N Name of star U P M1/M⊙ M2/M⊙ R1/R⊙ R2/R⊙ T1 T2 Referencesperiod of period of mass of mass of radius of radius of temperature temperatureapsidal elipsodal component 1, component 2, 1 component 2 component of of

rotation, rotation, in in in in 1 component, 2 component,years days the Sun mass the Sun mass the Sun radius the Sun radius K K

1 BW Aqr 5140 6.720 1.48 1.38 1.803 2.075 6100 6000 1,22 V 889 Aql 23200 11.121 2.40 2.20 2.028 1.826 9900 9400 3,43 V 539 Ara 150 3.169 6.24 5.31 4.512 3.425 17800 17000 5,12,24,674 AS Cam 2250 3.431 3.31 2.51 2.580 1.912 11500 10000 7,135 EM Car 42 3.414 22.80 21.40 9.350 8.348 33100 32400 86 GL Car 25 2.422 13.50 13.00 4.998 4.726 28800 28800 97 QX Car 361 4.478 9.27 8.48 4.292 4.054 23400 22400 10,11,128 AR Cas 922 6.066 6.70 1.90 4.591 1.808 18200 8700 14,159 IT Cas 404 3.897 1.40 1.40 1.616 1.644 6450 6400 84,85

10 OX Cas 40 2.489 7.20 6.30 4.690 4.543 23800 23000 16,1711 PV Cas 91 1.750 2.79 2.79 2.264 2.264 11200 11200 18,1912 KT Cen 260 4.130 5.30 5.00 4.028 3.745 16200 15800 20,2113 V 346 Cen 321 6.322 11.80 8.40 8.263 4.190 23700 22400 20,2214 CW Cep 45 2.729 11.60 11.10 5.392 4.954 26300 25700 23,2415 EK Cep 4300 4.428 2.02 1.12 1.574 1.332 10000 6400 25,26,27,616 α Cr B 46000 17.360 2.58 0.92 3.314 0.955 9100 5400 28,2917 Y Cyg 48 2.997 17.50 17.30 6.022 5.680 33100 32400 23,3018 Y 380 Cyg 1550 12.426 14.30 8.00 17.080 4.300 20700 21600 3119 V 453 Cyg 71 3.890 14.50 11.30 8.607 5.410 26600 26000 17,32,3320 V 477 Cyg 351 2.347 1.79 1.35 1.567 1.269 8550 6500 34,3521 V 478 Cyg 26 2.881 16.30 16.60 7.422 7.422 29800 29800 36,3722 V 541 Cyg 40000 15.338 2.69 2.60 2.013 1.900 10900 10800 38,3923 V 1143 Cyg 10300 7.641 1.39 1.35 1.440 1.226 6500 6400 40,41,4224 V 1765 Cyg 1932 13.374 23.50 11.70 19.960 6.522 25700 25100 2825 DI Her 29000 10.550 5.15 4.52 2.478 2.689 17000 15100 44,45,46,4726 HS Her 92 1.637 4.25 1.49 2.709 1.485 15300 7700 48,4927 CO Lac 44 1.542 3.13 2.75 2.533 2.128 11400 10900 50,51,5228 GG Lup 101 1.850 4.12 2.51 2.644 1.917 14400 10500 1729 RU Mon 348 3.585 3.60 3.33 2.554 2.291 12900 12600 54,5530 GN Nor 500 5.703 2.50 2.50 4.591 4.591 7800 7800 56,5731 U Oph 21 1.677 5.02 4.52 3.311 3.110 16400 15200 53,58,3732 V 451 Oph 170 2.197 2.77 2.35 2.538 1.862 10900 9800 59,6033 β Ori 228 5.732 19.80 7.50 14.160 8.072 26600 17800 61,62,6334 FT Ori 481 3.150 2.50 2.30 1.890 1.799 10600 9500 6435 AG Per 76 2.029 5.36 4.90 2.995 2.606 17000 17000 23,2436 IQ Per 119 1.744 3.51 1.73 2.445 1.503 13300 8100 65,6637 ζ Phe 44 1.670 3.93 2.55 2.851 1.852 14100 10500 11,6738 KX Pup 170 2.147 2.50 1.80 2.333 1.593 10200 8100 2139 NO Pup 37 1.257 2.88 1.50 2.028 1.419 11400 7000 11,6940 VV Pyx 3200 4.596 2.10 2.10 2.167 2.167 8700 8700 70,7141 YY Sgr 297 2.628 2.36 2.29 2.196 1.992 9300 9300 7242 V 523 Sgr 203 2.324 2.10 1.90 2.682 1.839 8300 8300 7343 V 526 Sgr 156 1.919 2.11 1.66 1.900 1.597 7600 7600 7444 V 1647 Sgr 592 3.283 2.19 1.97 1.832 1.669 8900 8900 7545 V 2283 Sgr 570 3.471 3.00 2.22 1.957 1.656 9800 9800 76,7746 V 760 Sco 40 1.731 4.98 4.62 3.015 2.642 15800 15800 7847 AO Vel 50 1.585 3.20 2.90 2.623 2.954 10700 10700 7948 EO Vel 1600 5.330 3.21 2.77 3.145 3.284 10100 10100 21,6349 α Vir 140 4.015 10.80 6.80 8.097 4.394 19000 19000 80,81,6850 DR Vul 36 2.251 13.20 12.10 4.814 4.369 28000 28000 82,83

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