proposition of pathways modulation probability ...€¦ · 8/5/2018 · 268 firas mohammed ali...
TRANSCRIPT
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Advanced Studies in Theoretical Physics
Vol. 12, 2018, no. 6, 267 - 280
HIKARI Ltd, www.m-hikari.com
https://doi.org/10.12988/astp.2018.8729
Proposition of Pathways Modulation Probability,
Generalized Liquid Drop Model Methods to
Determine the Qα-Value of Heavy and
Super Heavy Nuclei
Hala Akram Hadi and *FathiFiras Mohammed Ali
, IraqMosul, University , MosulCollege of Science sics Department,Phy
authorCorresponding *
Copyright © 2018 Firas Mohammed Ali Fathi and Hala Akram Hadi. This article is distributed
under the Creative Commons Attribution License, which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.
Abstract
The Q- value of alpha decay of asset of heavy and super heavy nuclei chain from
Z=78 to 120 have been analyzed systematically within the propose method of
probability of modulation pathways (ppnn, pnpn, pnnp, nnpp, npnp and nppn)
beside the generalized Liquid Drop Model. The results are reasonable agreement
with the published experimental data for alpha decay Qα- value of studied nuclei.
The first method has shown the possibility to forming of alpha particle of any
proposed pathway. Also has been shown it is not significantly affected by nuclei
with closed shell or nearby. The second method also showed acceptable results
that corresponding to the experimental values of the wide range of the studied
nuclei that decay of alpha particle emission along with nuclei that dissolve
spontaneously. For this purpose, a computer program was prepared in Mat lab
software, to reduce many of the data, along with reducing many of the time and
effort. The values of unknown masses were obtain for some nuclei in atomic mass
units through another program was prepared in Mat lab software with high
accuracy. These methods may help in synthesis and identification of new heaviest
nuclei.
Keywords: Qα-Value, Alpha decay, Super heavy nuclei
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268 Firas Mohammed Ali Fathi and Hala Akram Hadi
1. Introduction
Alpha decay was discovered in France by Henri Becquerel [1] and it was
identified as 4He emission by Ernest Rutherford [2]. Manjunatha and Sridhar
selected the most probable projectile super heavy nuclei Z=126[3]. Also
Manjunatha and Somya studied the half lives of spontaneous fission, ternary
fission and cluster decay of this predicted nuclei Z=126 and compared with that of
alpha decay using the theoretical Qα –value[4].Dong et al., [5] studied the alpha
decay half lives of super heavy nuclei in the ground state depending on
theoretically Qα –value. In experiment one usually measures the alpha Qα-values
and half-lives, while one of the major goals of theory is to predict the half lives to
serve the experimental design. As one of the crucial quantity for a quantitative
prediction of decay half-life, Qα-value strongly affect the calculation of the half-
life due to the exponential law [Geigger - Nuttal]. Therefore, it is extremely
important and necessary to obtain an accurate theoretical Qα-Value in reliable
half-life prediction during the experiments design [6]. In fact, it is a challenge to
interpret the existing decay data in literature, with theoretical model in order to
better understanding the complex nuclear structure phenomena and reaction
mechanism [7]. Several studies of research groups have been developed a nuclear
mass formula, which predicts the Qα-Value of various decays including β-decay,
proton-emission, and α-decay in the nuclide region, including the extremely have
mass region [8, 9, 10]. Dong et.al. [11], derive an expression of Qα-Value based
on the Liquid Drop Model, which can be used as an input to quantitatively predict
the half-lives of unknown nuclei. The present study is an attempt to understand
the nuclear structure of heavy and super heavy nuclei, as well as understanding
the mechanism of formation of the alpha particle and its emission. Intensive
efforts have been made to explain other aspect of the nuclear structure of another
nuclei as in [12, 13].The aim of this paper to propose the pathways modulation
probability as a new formula to determine the Qα-Value of heavy and super heavy
from Z=78 to 120 (even-even and even-odd nuclei) with high accuracy to predict
the half-lives of all nuclei understudy especially at the super heavy nuclei. For the
same purpose, another method was proposed based of the idea of modification of
Liquid Drop Model in determine the Qα-Value of the nuclei mentioned above.
2. Theory
2.1 Theoretical framework of the pathways modulation probability method
Each nucleon (proton and neutron) in any nucleus moves in any orbit with a
definite angular momentum comprising the vector sum of orbit and spin
components. One of the major difference in electrons distribution within atomic
orbital as well as nucleons distribution within a nucleus orbital is the existence of
two families of shells inside the nucleus. One of them belongs to the proton
distribution and the other belongs to neutron distribution. When these shells are
happened to be fully filled according to its allowed number, nuclei that belong to
these shells are considered to be fully stable. The nuclei containing 2, 8, 20, 50,
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Proposition of pathways modulation probability … 269
82, 126 neutrons or protons and the super heavy nuclei containing Z=112,114,
116, N=122,172,174 are considered to be exceptionally stable. Nuclei with both
types of completely shells filled are the most stable. Thus, the pb 82208 nucleus with
82 protons and 126 neutrons is essentially stable. Thus in the nucleus pb,82210 the
last proton (number 82) has a high binding energy of 8.37MeV (according to
Eq.2).In order to add one more proton to form Bi83211 , a certain amount of energy is
needed, while adding another proton needs an additional amount of energy to
form po84212 . The basic principle that we have adopted in present method is that
any heavy nucleus can decay with a massive alpha particles emission if the sum of
the separation energies of two protons and another two neutrons has less alpha
binding energy (28.3MeV) [14]. Another principle that has been adopted in this
method is the proposition that there are probability pathways for the formation of
the parent nucleus to separate the two neutrons and two protons from it. That is to
emit the massive alpha particles an independent entity, then the decay energy Qα-
Value can be calculate after summing the total separation energies of all protons
and neutrons (2p+2n) and subtracting it from the binding energy of alpha particles
(28.3Mev) i.e.
Qα−value = B. E(α−particle) − Stot (1)
Where B. E(α−particle) is the binding energy of alpha particle, Stot is the total separation energy of the two protons and two neutrons, Qα−value is the energy of alpha decay.
The proposed pathways can be illustrated by only six probabilities, as follow
1- p→p→n→n (Separation of proton, proton, neutron and neutron)
2- p→n→p→n (Separation of proton, neutron, proton and neutron)
3- p→n→n→p (Separation of proton, neutron, neutron and proton)
4- n→n→p→p (Separation of neutron, neutron, proton and proton)
5- n→p→n→p (Separation of neutron, proton, neutron and proton)
6- n→p→p→n (Separation of neutron, proton, proton and neutron)
For example, take the parent nucleus of U92234 that gives the experimental Qα-Value
as by (4.86MeV), the probability of forming the first pathway can be applied to calculate the separation energy of last two protons using the following equation twice [15].
Sp = [ MZ−1A−1
N − MZA
N]c2 + Mp c
2 (2)
Where MZ−1A−1
N, MZA
Nand Mp is the masses of daughter, parent nucleus and proton respectively (in amu). And using the following equation twice, to determine the separation energy of the last two neutrons.
Sn = [ MZA−1
N−1 − MZA
N]c2 + Mnc
2 (3)
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270 Firas Mohammed Ali Fathi and Hala Akram Hadi
Where MZA−1
N−1, MZA
N and Mn is the masses of the daughter, parent and neutron respectively (in amu), Sp & Sn is the separation energy of proton and neutron respectively.
The total separation energy of the last two protons is (6.6331MeV+5.2469MeV), and the total separation energy of the last two neutrons is (6.4405MeV+5.1175MeV).Finally, Eq.(1) can be used to obtain the Qα-value of the U 92
234 nucleus, which is equal to
Qα calc.−value = 28.3MeV − (6.6331 + 5.2469 + 6.4405 + 5.1175)MeV = 4.862 MeV
This result is consistent with the experimental value of Qα (4.86MeV) and by comparison it does not exceed (0.04٪).According to the first path, the decay mode of the U92
234 nucleus can be expressed as:
Up→92
234 pap→91
233 Th90232
n→ Th
n→ Th90
23090
231
The separation energy of last proton can be calculated by the parent nucleus U92234 ,
while the separation energy of the other last proton can be calculated by the pa91233
nucleus (not from the parent core) .The separation energy of the last neutron can be calculated by the Th90
232 nucleus and the separation energy of the other last neutron can be calculated by the Th90
231 nucleus, so here dose the pathway end up. This method can be applied to the rest of the pathways. Based on these data, it can be said that, if the Qα-value for the other pathways is found to be comparable with Qα-value of the first pathway, the proposed method is considered reliable in determining the Qα-values. Hence, this method can be generalized to all heavy and super heavy nuclei under study with contentment and acceptability. Each of the six pathways has a decay mode which is different from the other. There is a certain point at which the method is no longer valid, that is when the separation process of the last two protons and two neutrons are not from the parent nucleus, as it will inevitably reach a wrong result which does not fit with the experimental values. For example, when separating two protons and two neutrons out of the parent nucleus U92
234 , the separation energy is equal to
S2p + S2n = (6.6331 + 6.6331) + (6.845 + 6.845) = 26.9562MeV
By applying Eq.(1), a value of Qα (1.343MeV) will be obtained and that is far
from the experimental value (4.86MeV).It is also far from the calculated value
(4.862MeV),as mentioned earlier.
2.2 Unknown masses calculation of some nuclei
When conducting calculation with respect to the separation energy of protons and
neutrons within the proposed pathways. All the values of the atomic mass (amu)
of parent and daughter nuclei with the other nuclei within any studied pathway
must be known. Of course, it was not initially possible to obtain all these value, so
an alternative way to obtain those values, using the semi-empirical formula of
particular nucleus was tracked, in the following form [16]. M(Z,A) = Zmp + Nmn − B(A,Z) c
2⁄ (4)
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Proposition of pathways modulation probability … 271
Where M(A,Z) is the mass of particular nucleus, Z is the number of protons, N is the number of neutrons, mp is the proton mass (1.007825 amu), mn is the neutron mass (1.008665 amu), B(A,Z) is the binding energy of a particular nucleus.
The B(A,Z) can be obtained, using Liquid Drop Model represent by the following formula [16].
B(A,Z) = avA − asA2 3⁄ − ac
Z2
A1 3⁄− asy
(N−Z)2
A± δ (5)
Where A is Mass number of particular nucleus
av = 15.835MeV, as = 16.8MeV, ac = 0.703MeV, asy = 24.8MeV, ap = 11.2MeV,
δ = ±apA−1 2⁄ MeV
By substituting equation(5) in equation(4), the unknown nucleus mass can be obtained as the following:
M(Z,A) = Zmp + Nmn − (avA − asA2 3⁄ − ac
Z2
A1 3⁄+ as
(N−Z)2
A± δ) c2⁄ (6)
And from substituting M(Z,A) value either in equation (2) or (3) the Qα-value (Eq.1) can be established. This was done by working out a computer program in the language of Mat lab through the formula of equation (6) with the data of equation (2) and equation (1). To be precise, a global program known as ''binding energy'' was used, which gave values very close to the values of the program that has been worked out.
2.3 Theoretical framework of the generalized liquid drop model
The local formula of binding energy for nuclei with 78 ≤ 𝑍 ≤ 120 of even-even and even-odd nuclei[17] using the Liquid Drop Model this is given by B(Z, A) = Bv + Bs + Bc + Ba + Bp
= avA − asA2 3⁄ − acZ
2A−1 3⁄ − asy (A
2− Z)
2
A−1 + apδA−1 2⁄ (7)
Where Bv , Bs , Bc are respectively the volume, surface and the coulomb energy between the protons. Note that Bs arises because nucleus has surface, where the nucleons interact with only on the average, half as many nucleon as those in the interior, and may be considered as a correction to Bv. In this formula the average pairing energy Bp is described by apδA
−1 2⁄
𝛿 = {1 for even − even nuclei0 for odd A nuclei
−1 for odd − odd nuclei
Means that the strengths of the (nn) and (pp) pairing are considered to be equal, and that the correlations between (np) and perhaps other few-body correlations (i.g., α correlation) are ignored [17].While the av, as, ac, asy, ap represent the volume,
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272 Firas Mohammed Ali Fathi and Hala Akram Hadi
surface, coulomb, symmetry and pairing constant, these have been determined by[16] to be
av = 15.835MeV, as = 16.8MeV, ac = 0.703MeV, asy = 24.8MeV, ap = 11.2MeV
The energy release of alpha decay of heavy and super heavy nuclei given by the
Liquid Drop Model is (14)
Qα = M(A, Z) − M(A − 4, Z − 2) − M(4,2) (8)
In order for α-decay to occur energy must be conserved, such that Qα value for α-decay can be determine by:
Qα = Bα + B(Z − 2, A − 4) − B(Z, A) (9) By substitution equation (7) in eq.(9) can be obtained the following equation
Qα = Bα + [av(A − 4) − avA] + [asA2 3⁄ − as(A − 4)
2 3⁄ ] + [−ac(Z − 2)2(A − 4)−1 3⁄ ] +
acZ2A−1 3⁄ + [−asy (
N−Z
2)
2(A − 4)−1 + asy (
N−Z
2)
2A−1] + [apδ(A − 4)
−1 2⁄ −
apδ(A)−1 2⁄ ] (10)
The term of B(4,2) in the binding energy of alpha particle which is equal to
28.3Mev.the volume energy(av) is only constant and the surface energy(as) can be
regarded a constant since it is varies very little in this region there for the above
formula can be simplified further, the binomial theory[18] was used. It is found
that the pairing energy (ap) contribute very little to the Qα-value and can be
neglected [17], and the surface energy (as term) can be regarded a constant
because it varies little in this local region especially at super heavy nuclei and can
be neglected [11].Therefore, the previously mentioned formula can be simplified
further to
Qα = aZA−4 3⁄ (3A − Z) + b (
N−Z
A)
2+ e (11)
The best fit parameter are
a = 0.9373MeV, b = −99.3027MeV , e = −27.453MeV According to this formula(11)(i.g generalized Liquid Drop Model), and when it
employed to calculate Qα-value, the results are not very good with high deviations
between theoretical and experimental Qα-values with standard deviation equal
to(0.7798).It might be feasible to deduce a more accurate formula for Qα-value
with fewer parameters based on eq.(11). And for this purpose the term of relative
neutron excess (N−Z
A) was added in Eq.(7), to obtain another form of nuclear
binding energy, and substitute this formula in Eq.(11),the following form is
produced
Qα = aZA−4 3⁄ (3A − Z) + b (
N−Z
A)
2
+ e + c [(N−2)−(Z−2)
A−4−
N−Z
A] (12)
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Proposition of pathways modulation probability … 273
Where a, b, e they are the same constant in Eq.(11)but the (c) constant was
obtained the best fit to the nuclei with 78 ≤ 𝑍 ≤ 120 to give a little deviation between the theoretical and experimental binding energy and so
c = {450 for nuclei with78 ≤ Z ≤ 90
170.65 for nuclei with 92 ≤ Z ≤ 120
The last term of Eq.(12) which was extremely important in Qα-value suitability
and its approach to experimental value. The term of relative neutron excess was
suggested by the researchers (Ali & khalil)in Ref.(19).
calc.-αQ and .exp -αQ etweenCalibration curves b 2.4
In order to overcome the long and burdensome calculations for more than 4500
times, the prepared program was used, and in order to process the data that was
obtained and to show it in simple and clear way, in addition to obtaining a
relationship between the experimental and theoretical Qα-value, the (Treat
function) was used in the Matlab software. The horizontal axis is arranged in
ascending order according to the vertical axis of matlab. The standard deviation
(σ) and the roots mean square deviation (rmsd) of the Qα-value of all nuclei (for any proposed pathway) under study and for generalized Liquid Drop Model
method are as follows [20,21]
σ = ∑ |Qαexp. −Qαcalc. | N⁄Ni=1 (13)
rmsd = √∑ (Qαexp. −Qα. calc)2 N⁄Ni=1 (14)
3. Result and Discussion
The standard deviations (σ) are equal to (0.026, 0.027, 0.028, 0.021, 0.022, 0.018) and the roots mean square deviations are equal to (0.1, 0.098, 0.098, 0.076,
0.076, 0.062 ) for ppnn ,pnpn ,pnnp ,nnpp ,npnp and nppn pathway respectively,
i.e. the very little deviation of Qα-value confirm the suggested method of
probability of modulation pathways that will be very useful for experimentalists.
Furthermore the calculation of Qα versus mass number (A) for ppnn pathway are
shown graphically in Fig.(1) which reveals a Qα-value increase as the mass
number (A) increases on the whole. It also shows that the Qα-value decrease by
increasing the mass number of isotopes of a particular element. The behavior of
Qα-value for the rest of the suggested pathways will certainly give the same
behavior because the values of the standard deviations and root mean square
deviations are close to the all pathways.
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274 Firas Mohammed Ali Fathi and Hala Akram Hadi
ass number(A) according to the mversus value-αQ he theoreticalT Figure1:proposed method (ppnn pathway).
While Fig (2) and Fig (3) illustrate the relationship between the difference of the
experimental and theoretical value of Qα with both atomic number and neutron
number respectively of the studied nuclei within the ppnn pathway.
Figure 2: The relation between Qα exp.- Qα calc. with atomic number (Z)for(ppnn) pathway
eutron number(N) for nwith calc. αQ -exp. αQ nhe relation betweeT :3 Figureppnn) pathway.)
The very slight deviation in Fig.(2) and Fig.(3), indicate the super agreement
between experiment and theoretical value of Qα even at the stable nuclei that have a magic number in its proton (Z=108,112,114,116)or in its neutron (N=122,172,174)
0
2
4
6
8
10
12
14
170 180 190 200 210 220 230 240 250 260 270 280 290 300
Qα
Calc
.(M
eV
)
Mass number(A)
-0,8-0,7-0,6-0,5-0,4-0,3-0,2-0,1
00,10,20,30,40,50,60,7
70 80 90 100 110 120
Qα
exp
. -Qα
calc
.(M
eV
)
Atomic number(Z)
-0,8
-0,6
-0,4
-0,2
0
0,2
0,4
0,6
90 100 110 120 130 140 150 160 170 180
Qα
ex
p. -Qα
ca
l.(M
eV
)
Neutron number (N)
-
Proposition of pathways modulation probability … 275
or both, as well as at the nuclei located near the nuclei that posses magic
number(but with slightly higher deviation compared to other nuclei),which in turn
shows the extent of the possibility and the high acceptability shown by the
proposed method in estimating the Qα-value within the pathway ppnn. The
deviations between the Qα exp. and Qα calc. for the rest pathways certainly give
the same behavior due to the values of the standard deviations, moreover, the
roots mean square deviations came close to all other pathways. The Fig. (4 a, b, c,
d, e, f) shows the strong relationship between the experimental and theoretical
values of Qα produced by the application of the program which contained the
(Treat function) for all the proposed pathways. That is to form the alpha particle
moment of escape from the parent nucleus for all nuclei under study. The results
obtained through the application of the above program summarized in Table 1
which include the calibration equations containing the slope values and the
constants of calibration.
according to svalue-αhe experimental versus the theoretical QT :4Figure
ppnn, pnpn, pnnp, nnpp, npnp, nppn pathways for all nuclei under study
0 2 4 6 8 10 12 140
2
4
6
8
10
12
14
Q alpha calc.(MeV)
Q alp
ha e
xp.(M
eV)
Figure (a) ppnn
y = 0.99*x + 0.087
data 1
linear
0 2 4 6 8 10 120
2
4
6
8
10
12
Q alpha calc.(MeV)
Q alp
ha e
xp.(M
eV)
Figure (c) pnnp
y = 0.99*x + 0.084
data 1
linear
0 2 4 6 8 10 120
2
4
6
8
10
12
Q alpha calc.(MeV)
Q alp
ha e
xp.(M
eV)
Figure (e) npnp
y = 1*x + 0.039
data 1
linear
0 2 4 6 8 10 12 140
2
4
6
8
10
12
14
Q alpha calc.(MeV)
Q alp
ha e
xp.(M
eV)
Figure (b) pnpn
y = 0.99*x + 0.083
data 1
linear
0 2 4 6 8 10 120
2
4
6
8
10
12
Q alpha calc.(MeV)
Q alp
ha e
xp.(M
eV)
Figure (d) nnpp
y = 1*x + 0.042
data 1
linear
0 2 4 6 8 10 120
2
4
6
8
10
12
Q alpha calc.(MeV)
Q alp
ha e
xp.(M
eV)
Figure (f) nppn
y = 0.99*x + 0.063
data 1
linear
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276 Firas Mohammed Ali Fathi and Hala Akram Hadi
TABLE I: The calibration equation for all pathway
Fig.(4) and Table.1show that the slope values are about (0.99-1) for all pathways. This mean that there is a close consensus with accuracy between the experimental and theoretical value of Qα .Therefore, the proposed method is one of the methods that can be used to characterize the alpha particle emission, and to determine the half-life with high accuracy a long side the values of standard deviations and the roots mean deviations. That is due to the fact that there has been nearly no approach which can provide an accurate Qα-value theoretically with deviation less than 0.5MeV.Hence, predicting the half-life with good accuracy is proven to be a very difficult work, since the Qα-value of the reference nuclei will have to be extremely precise, especially for super heavy nuclei which still await independent verification by the other laboratories. This task is not easy as the new super heavy nuclei from isolated island tend to be not linked through the α-decay chains with any known nuclei, making theoretical support ever more important and necessary. In spite of the shell closed should playing a particular an important role in the heavy and super heavy system. However, that is despite of the fact that there are associated problem with the closed shell. The Fig.(5) which represent the relationship between the theoretical Qα-value versus the mass number (A) according to generalized Liquid Drop Model , where we observe that the behavior is similar to the behavior of the first method.
Figure (5) The theoretical Qα-value versus Mass number(A) according to
generalized Liquid Drop Model
Calibration equation Pathways
Y=0.99*X+0.087 ppnn
Y=0.99*X+0.083 pnpn
Y=0.99*X+0.084 pnnp
Y=1*X+0.042 nnpp
Y=1*X+0.039 npnp
Y=0.99*X+0.063 nppn
2468
101214
160 180 200 220 240 260 280 300
Qα
Calc
.(M
eV
)
Mass Number(A)
-
Proposition of pathways modulation probability … 277
While Fig.(6)and Fig.(7) represent the relationship between the difference of the
experimental and theoretical Qα-value once with the number of protons (Z) and
once with the number of neutrons (N).
Figure (6) The relation between Qα exp.-Qα Calc.with atomic number(Z) according to generalized Liquid Drop Model
Figure (7) The relation between Qα exp.- Qα Calc. with neutron number(N)
according to generalized Liquid Drop Model
The deviation in Fig. (6,7) .Indicate the acceptable agreement with experimental and theoretical value of Qα-even at the stable nuclei that have magic number but less accurately then the method suggest by pathways. As we can infer it through the values of standard deviation (𝜎 = 0.32) and the root mean square deviation (rmsd=0.411) for generalized Liquid Drop Model. Also we can say, the precision is improved by a factor(59%), when comparing between the standard deviation of the formula (11) with standard deviation of the formula (12)which contain a term of relative neutron excess. Since the Qα-values can be calculate with acceptable accurately, one can expect that the experimental single-and two nucleon separation energies, and that the values of unknown nuclei in this region can be predicted reliably. The experimental Qα-values of the newly synthesized nucleus 298120 is (12.62MeV) is taken from Fig (5). The Qα-values is deduced from the kinetic energy of α-particle(Eα) by using the standard relation [22].
Qα = [Ap
Ap−4] Eα + (0.63Zp
7 5⁄ − 80.0Zp2 5⁄ ) ∗ 10−6MeV
-2
-1
0
1
2
90 100 110 120 130 140 150 160 170 180 190
Qα
exp
. -
Qα
Calc
.(M
eV
)
Neutron Number(N)
-2
-1
0
1
2
70 80 90 100 110 120 130
Qα
exp
. -
Qα
Calc
.(M
eV
)
Atomic Number(Z)
-
278 Firas Mohammed Ali Fathi and Hala Akram Hadi Where Zp and Ap are the proton and mass number of the α-emitter, respectively,
from the measured α kinetic energy Eα=12.367Mev [23], we obtain its
Qα=12.587,which is very close to the experimental value and our result from
improved formula is 12.9MeV.also close to the experimental Qα-values.
4. Conclusion
The result of the present calculations of Qα-value are in excellent a agreement
with experimental data with very little deviation. Qα-value predictions are made
from many unknown nuclei from the region of Z=78 to 120 (even-even and even-
odd).This region is typically unstable with respect to α-decay. The proposed
method demonstrated its high accuracy in determining the Qα-values of all types
of nuclei studied for their high correlation with experimental data. This method
has shown the possibility to forming of alpha particle of any proposed pathway,
because the total sum of the separation energies are equal to any proposed
pathway. In this work, theoretical approach is in very close agreement as to the
position of closed shell. The simple program that was prepared, to reduce much of
the data due to the difficulty of showing them in tables, along with reducing much
of the time and effort we can conclude by proposing a generalized Liquid Drop
Model Method that there is acceptable consensus between the theoretical and
experimental values of Qα but with less accuracy as in the first method. We also
find that Qα-value dependence becomes increasingly weaker as the atomic number
increases on the whole, which implies that the uncertainty of the Qα-value is
smaller for heavier nuclei; thus, it is exactly what we expect to predict the α-decay
half life of super heavy nuclei (SHN).And the isotopes finally, the Qα-values
besides the half life perhaps insufficient to obtain more information about the
nuclear structure and other properties of SHN(such as rotational band, isomeric
states, and various deformations). In brief, by studying the decay channels, it is
possible to inter-relate most nuclear species on the energy time content basis and
to determine the regions greater stability which may help in synthesis and
identification of new heaviest nuclei.
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Proposition of pathways modulation probability … 279
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Received: July 21, 2018; Published: September 18, 2018
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