Modern Theory of Nuclear Structure, Exotic Excitations and Neutrino-Nucleus Reactions N. Paar Physics Department Faculty of Science University of Zagreb Croatia Croatiawww.phy.hr/~npaar Modern Theory of Nuclear Structure, Exotic Excitations and Neutrino-Nucleus Reactions Modern Theory of Exotic Nuclear Structure: Excitations, Weak Interaction Rates and Beyond NuPECC Meeting, Zagreb,

BEYOND THE MEAN FIELD Transitions between spherical and axially deformed shapes RMF+GCM DESCRIPTION OF NUCLEAR QUANTUM PHASE TRANSITIONS

COLLECTIVE EXCITATIONS IN NUCLEI: GIANT RESONANCES IVGDR ISGMR Self-consistent description of excitations : relativistic quasiparticle random phase approximation (RQRPA)

EXOTIC MODES OF EXCITATION IN NUCLEI REVIEW: Paar, Vretenar, Khan, Colò, Rep. Prog. Phys. 70, 691 (2007). exotic nuclei are characterized by weak binding of outermost nucleons, diffuse neutron densities, formation of the neutron skin and halo effect on multipole response new exotic modes of excitation Among the low-lying states, a single state has more distributed structure composed of many transitions from weakly bound neutron orbitals PYGMY DIPOLE RESONANCE (PDR)

PYGMY DIPOLE RESONANCES AND NEUTRON SKIN Adrich et al., PRL 95, (2005). Klimkiewicz, Paar, et al. PRC 76, (R) (2007) Result ( averaged 130,132 Sn) : a 4 = 32.0 ± 1.8 MeV

LAND Sn isotopes A.Krasznahorkay et al. PRL 82(1999)3216 PYGMY DIPOLE RESONANCES AND NEUTRON SKIN R n – R p : 130 Sn: 0.23 ± 0.04 fm 132 Sn: 0.24 ± 0.04 fm

EXOTIC MODES TOWARDS THE PROTON DRIP-LINE PROTON PYGMY DIPOLE RESONANCE Proton PDR is composed from transitions of weakly bound protons including those which are bound only due to the Coulomb barrier Centroid energy and B(E1) for low-lying states Paar, Vretenar, Ring, Phys. Rev. Lett. 94, (2005)

NEUTRINO-NUCLEUS REACTIONS ZXNZXN Z+1 X N-1 E RQRPA amplitudes RHB occupation probabilities Reduced matrix elements for the neutrino- nucleus cross section: Possible extrapolations towards exotic nuclei relevant for astrophysics without any adjustments of interaction parameters

RHB+RQRPA DISTRIBUTION OF CROSS SECTIONS OVER MULTIPOLARITIES The knowledge on spin-dipole excitations and higher multipolarities is essential for reliable description of neutrino nucleus cross sections! Paar, Vretenar, Marketin, Ring Phys. Rev. C 77, (2008)

e - NUCLEUS CROSS SECTIONS AVERAGED OVER NEUTRINO FLUX e FLUX Experimental flux of neutrinos obtained from + decay at rest

(ν μ,μ - ) ( cm 2 ) RPA(Volpe et al.)19.23 QRPA(Volpe et al.)20.29 CRPA(Kolbe et al.)18.18 PN-RQRPA10.97 EXP.(LSND)12 ± 0.3 ± 1.8 MUON NEUTRINO CAPTURE, EXOTIC ATOMS, … Self-consistent description of muon atom: FLUX

Supernova neutrino flux: Cross section averaged over Supernova neutrino flux CROSS SECTIONS FOR SUPERNOVA NEUTRINOS T[MeV]

Unified description of the structure of stable and nuclei far from stability, and reliable extrapolations toward the drip lines CONCLUDING REMARKS When extended to take into account the most important correlations, it describes deformations and shape-coexistence phenomena associated with shell evolution Insight into dynamics of exotic modes of excitation, neutrino- nucleus reactions, weak interaction rates of relevance for nuclear astrophysics

T. Nikšić, T. Marketin, D. Vretenar, Zhipan-Li University of Zagreb, Croatia G. A. Lalazissis Aristotle Universtity of Thessaloniki, Greece P. Ring Technische Universitaet Muenchen, Germany G.Colò Università degli Studi and INFN, Milano, Italy E. Khan IN 2 P 3 -CNRS/Université Paris-Sud, Orsay, France