Theoretical nuclear physicsTheoretical nuclear physics

Laura Elisa Marcucci (Univ. Pisa & INFN-Pisa)Laura Elisa Marcucci (Univ. Pisa & INFN-Pisa)

The Pisa Group

Ignazio Bombaci (Univ. Pisa & INFN-Pisa)Angela Bonaccorso (INFN-Pisa)Alejandro Kievsky (INFN-Pisa)Laura Elisa Marcucci (Univ. Pisa & INFN-Pisa)Sergio Rosati (Prof. Emerito, Univ. Pisa & INFN-Pisa)Michele Viviani (INFN-Pisa)

Adelchi Fabrocini (Univ. Pisa & INFN-Pisa, 1951-2006)

● ∼ 270 isotopes on Earth ● ≥ 1000 (not stable) isotopes, with A=2 … 300

Nuclei: system of interacting particles (neutron and proton = nucleon)Nucleon: system of elementary particles (quarks) held together by gluons

Laboratories

LawrenceLivermoreNationalLaboratory

... and in Japan (J-PARC, SPring-8, KEK, RIKEN, ...)

Best laboratories ... ever!

A computer simulation, basedon theoretical predictions, of the first

three seconds of a supernovae explosion[University of Chicago Flash Center]

Nuclear astrophysics⊂

Nuclear physics

Research activities in nuclear physics and Research activities in nuclear physics and astrophysicsastrophysics

1) What governs the transition of quark and gluons into nucleons and pions ⇔ Which are the “right” degrees of freedom

⇒ What is the nature of nuclear force

2) What is the origin of simple patterns in complex nuclei

⇔ Where are the proton/neutron drip lines

3) What is the nature of neutron stars and dense hadronic matter

4) What are the nuclear reactions that drive stars and stellar explosions ... and many more “astrophysical” questions

1) & 4): A. Kievsky, L.E. Marcucci, S. Rosati, M. Viviani2) A. Bonaccorso3) I. Bombaci

Research activity 1: Research activity 1: A. Kievsky, L.E. Marcucci, S. Rosati, M. VivianiA. Kievsky, L.E. Marcucci, S. Rosati, M. Viviani

Nuclear interaction: VNN

+VNNN

● Until ∼ 15 years ago

– VNN

+ VNNN

semi-

phenomenological

– VNN

with 40 parameters fitted ∼

to A=2 data 2/datum 1∼

– VNNN

: 2-3 parameters fitted ∼to B(A=3,4)

⇒ no simple connection to QCD

● Then ... chiral effective field theory (χEFT)

and Lattice QCD

Chiral Effective Field Theory (Chiral Effective Field Theory (χEFT)χEFT)● QCD → quark and gluons (“heavy” degrees of freedom)

● Nuclear physics → nucleons and pions (“light” degrees of freedom)

● EFT → processes with E ∼ p m∼π ≪ Λ

QCD 1 GeV ∼

►“heavy” d.o.f. integrated out → contact interactions with “light” d.o.f. and low-energy constants (LECs) obtained from experiment

►perturbative theory: matrix elements ∝ O(p/ΛQCD

)ν

● χEFT → implement EFT and spontaneous breaking of QCD's chiral symmetry

Advantages: a) “right” treatment of πN interaction b) nuclear force “hierarchy” → accurate V

NN+V

NNN

Disadvantage: limited to processes occurring at low-energy E∼ 1-2 mπ

S. Weinberg, Phys. Lett. B 251, 288 (1990); Nucl. Phys. B 363, 3 (1991)V. Bernard, N. Kaiser, and U.G. Meissner, Int. J. Mod. Phys. E 4, 193 (1995)...E. Epelbaum et al., Phys. Rev. C 66, 064001 (2002)D.R. Entem and R. Machleidt, Phys. Rev. C 68, 041001 (2003)E. Epelbaum, Prog. Part. Nucl. Phys. 57, 654 (2006)E. Epelbaum, H.W. Hammer, and U.G. Meissner, Rev. Mod. Phys. 81, 1773 (2009)

REVIEW

A. Kievsky et al., J. Phys. G: Nucl. Part. Phys. 35, 063101 (2008)

AA=3,4=3,4 bound and zero-energy scattering states bound and zero-energy scattering states

AV18 AV18/UIX N3LO N3LO/N2LO Exp.

B(3H) [MeV] 7.624 8.479 7.854 8.474 8.482

B(3He) [MeV] 6.925 7.750 7.128 7.733 7.718

B(4He) [MeV] 24.21 28.46 25.38 28.36 28.30

2and

[fm] 1.248 0.590 1.100 0.675 0.645(10)

4and

[fm] 6.346 6.343 6.342 6.342 6.35(2)

1an

3H

[fm] 4.29 4.10 4.20 3.99 4.98(29)4.45(10)

3an

3H

[fm] 3.73 3.61 3.67 3.54 3.13(11)3.32(2)

Accurate techniques to solve the few-body nuclear problem

Few-nucleon @ Pisa: only available method to study A=3,4 scattering states at low-energies ( keV ∼ astrophysical interest)

VNN

VNN

+ VNNN

VNN

VNN

+ VNNN

p-3He elastic scattering

M. Viviani et al., arXiv:1004.1306

M. Viviani et al., Phys. Rev. C 61, 064001 (2000)L.E. Marcucci et al., Phys. Rev. C 72, 014001 (2005) E.G. Adelberger et al., arXiv:1004.2318, Rev. Mod. Phys. in press

Application to reactions of astrophysical interest: Application to reactions of astrophysical interest: pp+d+d→→   33HeHe++γγ

- pp chain- Big Bang Nucleosynthesis(one of the largest uncertaintyfor the calculated 7Li abundance)

p+p→ d+e++νe

p+3He→ 4He +e++νe 

n+d→ 3H+γ

μ ­+d→ n+n+νμ

Reactions of astrophysical intereststudied over the years:

T.S. Park et al., Phys. Rev. C 67, 055206 (2003)

L. Girlanda et al., Phys. Rev. Lett. 105, 232502 (2010)

μ ­+3He→ 3H+ν

μ

L.E. Marcucci et al., Phys. Rev. C 83, 014002 (2011)

Research activity 2: A. BonaccorsoResearch activity 2: A. Bonaccorso

Sn

6He 0.9 MeV 806 msec8B 0.14 MeV 770 msec11Be 0.5 MeV 13.81 sec11Li 0.22 MeV 8.5 msec17F 0.6 MeV 64.5 sec19C 0.5 MeV 49 msec

Light nuclei weakly bound, p Halo, n Halo, Borromeian nuclei

T1/2

I. Tanihata, Prog. Part. Nucl. Phys. 35, 505 (1995)

● anomalous large radii● large diffuseness● inversion of shells● long tail of the wave functions

Fundamental research to define the drip lines

A. Di Pietro et al., Phys. Rev. Lett. 105, 022701 (2010)

11Be

10 Be

9 Be LNS - Catania

ISOLDE - CERN

dσ/dΩ elastic reduced by ~ 50% for 11Be Possible explanation: breakup channel → neutron-halo

asi = diffuseness. For “normal” systems: a

si ~ 0.65 fm

Predicted by A. Bonaccorso and F. Carstoiu, Nucl. Phys. A 706, 322 (2002): asi =3.2 fm

99BeBe--1010Be-Be-1111BeBe

Borromean and unbound nucleiBorromean and unbound nucleiFirst evidence of a p1/2 g.s. for 13Be

G. Blanchon, PhD Thesis, Univ. of Pisa 2008,

http://www.infn.it/thesis

H. Simon et al., Nucl. Phys. A 791, 267 (2007) - GSI data

G. Blanchon et al., Nucl. Phys. A 784, 49 (2007) - theory

recently confirmed by Y. Kondo et al., Phys. Lett. B 690, 245 (2010)

Studies to determine Vn-core

⇒ predict structure of other nuclei

G. Blanchon et al., Phys. Rev. C 82, 034313 (2010)

14Be+12C → n + 12 Be + X

1010Li-Li-1111LiLi

Spectrum of 10Li from 11Li fragmentation 11Li+12C → n + 9 Li + X

G. Blanchon et al., Nucl. Phys. A 791, 363 (2007)

G. Blanchon et al., Nucl. Phys. A 739, 259 (2004)

H.B. Jeppensen et al., Phys. Lett. B 642, 449 (2006)

s

p

d

10Li ground state is a virtual s-state (see cold atoms)

s

p

9 Li(2 H, p)

Research activity 3: I. Bombaci Research activity 3: I. Bombaci

Neutron Stars

M = (1 - 2) MSUN

R ~ 10 kmρ

c = (4 - 8) ρ

0

R/Rg ~ - 2 4

MSUN

= 1.989 x 1033 g (mass of the Sun)

ρ 0= 2.8 x 1014 g/cm3 (nucl. saturation dens.)

Rg ≡ 2GM/c2

(Schwarzschild radius)

Space-time in strong Space-time in strong gravity (GR)gravity (GR)

Structural Structural properties properties of Neutron of Neutron

StarsStars

““measured” measured” properties of properties of Neutron StarsNeutron Stars

Dense hadronic matter EOSDense hadronic matter EOS

Quantum many-body Quantum many-body syst. under strong syst. under strong

interactionsinteractions

Emission models (PSR mechanism, NS atmosphere). ISM composition. Distance.

Observational dataObservational data

Nucleonic Stars

Hyperon Stars

Hybrid Stars

Strange Stars

Hadronic Stars

Quark Stars

The core of the most massive Neutron Stars is one of the best candidates in the Universe where a deconfined phase of hadronic matter (quark matter) can be found

The core of the most massive Neutron Stars is one of the best candidates in the Universe where a deconfined phase of hadronic matter (quark matter) can be found

Bombaci and Drago, INFN notizie 13, 15 (2003)

Microscopic EOS for hyperonic matter Microscopic EOS for hyperonic matter

and hyperonic star structureand hyperonic star structure

I. Vidaña et al., Astron. & Astrophys. 399, 687 (2003)

I. Bombaci, Eur. Phys. J. A 31, 810 (2007)

EOS for hybrid star structureEOS for hybrid star structure

Quark matter nucleation in Neutron Stars and in proto-Neutron Stars

1) Mcr , critical mass of HS

2) Two families of compact stars

3) Stellar conversion

HSQS

Econv ∼ 1053 erg

possible energy source

for some GRBs

Z. Berezhiani et al., Astrophys. Jour. 586, 1250 (2003)

I. Bombaci et al., Astrophys. Jour. 614, 314 (2004)

G. Lugones and I. Bombaci, Phys. Rev. D 72, 065021 (2005)

I. Bombaci et al., Astron. & Astrophys. 462, 1017 (2007)

I. Bombaci et al., Phys. Rev. D 77, 083002 (2008)

I. Bombaci et al., Phys. Lett. B 680, 448 (2009)

I. Bombaci et al., Astron. & Astrophys. 528, A71 (2011)

Hadronic Stars above a threshold value of their gravitational mass are metastable to the conversion to Quark Stars (QS)

Where are we going: research activity 1Where are we going: research activity 1

➢ NNN force from χEFT at the same χ-order as NN force➢ Solve old-standing “puzzles” in few-body systems L. Girlanda et al., arXiv:1102.4799, submitted to Phys. Rev. C

➢ Use χEFT for nuclear electro-weak current operators: consistent study of fundamental reactions S. Pastore et al., Phys. Rev. C 80, 034004 (2009) L. Girlanda et al., Phys. Rev. Lett. 105, 232502 (2010) L.E. Marcucci et al., Phys. Rev. C 83, 014002 (2011)

➢ Ab initio calculations of A≥4 nuclear systems Few techniques for A>4 nuclear systems (NCSM, GFMC/VMC, AFDMC);

none for scattering states

Hyperspherical Harmonics methods (Pisa) can be pushed to study these systemsHyperspherical Harmonics methods (Pisa) can be pushed to study these systems

M. Gattobigio et al., Phys. Rev. C 83, 024001 (2011)

➢ Studies of Parity Violating (PV) strong interaction (W/Z exchange between q in N & q in π): large experimental and theoretical activity

R. Schiavilla et al., Phys. Rev. C 78, 014002 (2008)M. Viviani et al., Phys. Rev. C 82, 044001 (2010)

➢ Detailed study of reactions of astrophysical interest

L.E. Marcucci et al., Nucl. Phys. A 777, 111 (2006)

Big Bang Nucleosynthesis (BBN)

abundances of primordial light nuclei(d,3He, 4He, 7Li)

Cosmic Microwave Background

Where are we going: research activity 2Where are we going: research activity 2Until 2009: EURISOL Design Study

possibility to influencethe different research-lines

Where are we going: research activity 3Where are we going: research activity 3

A massive NS: PSR J1614–2230 M = (1.97 ± 0.04) MSUN

Demorest et al., Nature 467, 1081 (2010)

Microscopic EOS for hyperonic matter: “very soft” EOS

non compatible with PSR J1614–2230

Need for extra pressure at high density

Need for improved VNY

and VYY

and

three-body forces (VNNY

VNYY

VYYY

)

A preliminary study:

I. Vidaña et al., Eurphys. Lett. 94, 11002 (2011)

Large experimentalactivity (GSI, J-PARC)

Summarizing ...Summarizing ...

● Recent activity (2008-2011)

– 37 publications on peer-reviewed journals (19 on journals with IF > 3)

– 45 contributions to international conferences (34 invited)

● Following arXiv:1103.3216 (WoS, PY=2008, SA= Nucl. Phys., TS=theory)

All papers

Top-10 % papers