First Gogny conference, TGCC December 2015 DAM, DIF, S. Péru QRPA with the Gogny force applied to...

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First Gogny conference, TGCC December 2015 DAM, DIF, S. Péru (Q)RPA approaches describe all multipolarties and all parities, collective states and individual ones, low energy and high energy states with the same accuracy. But small amplitude approximation i.e. « harmonic » nuclei δ E/ δ q=0 δ 2 E/ δ q 2 >0 E Beyond static mean field … with 5DCH or QRPA 5 Dimension Collective Hamiltonian describes ground state and excited states within configuration mixing : quadrupole vibration and rotational degrees of freedom. Exp. SM 5DCH HFB+D1S D. Sohler et al, PRC 66, (2002) S.Péru and M. Martini, EPJA (2014) 50: 88.

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First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru QRPA with the Gogny force applied to spherical and deformed nuclei M. Dupuis, S. Goriely, S. Hilaire, F. Lechaftois, M. Martini and Sophie Pru First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Static mean field (HFB) for Ground State Properties : Masses Deformation (Single particle levels) Beyond static mean field approximation (5DCH or QRPA) for description of Excited State Properties Low-energy collective levels Giant Resonances Amedee database :S. Hilaire & M. Girod, EPJ A33 (2007) 237 Gogny Reminder First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru (Q)RPA approaches describe all multipolarties and all parities, collective states and individual ones, low energy and high energy states with the same accuracy. But small amplitude approximation i.e. harmonic nuclei E/ q=0 2 E/ q 2 >0 E Beyond static mean field with 5DCH or QRPA 5 Dimension Collective Hamiltonian describes ground state and excited states within configuration mixing : quadrupole vibration and rotational degrees of freedom. Exp. SM 5DCH HFB+D1S D. Sohler et al, PRC 66, (2002) S.Pru and M. Martini, EPJA (2014) 50: 88. First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru 5DCH : A. Obertelli, et al, Phys. Rev. C 71, (2005) HFB+QRPA versus HFB+5DCH with the same interaction N=16 isotones Sn isotopes (Z=50) S. Pru and M. Martini, EPJA (2014) 50: 88. First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru S. Pru and M. Martini, EPJA (2014) 50: 88. Ni isotopes (Z=28) Two shell (N= 28, 50) and one sub-shell (N=40) closures ! For deformed nuclei the first 2 + state is rotational 78 Ni is predicted doubly magic HFB+QRPA versus HFB+5DCH with the same interaction First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru RPA approaches describe all multipolarties and all parities, collective states and individual ones, low energy and high energy states with the same accuracy. Within the small amplitude approximation, i.e. harmonic nuclei E/q=0 2 E/q 2 >0 E S. Pru, H. Goutte, Phys. Rev. C 77, , (2008) M. Martini, S. Pru and M. Dupuis, Phys. Rev. C 83, (2011) S. Pru et al, Phys. Rev. C 83, (2011) Axially symetric deformed QRPA with Gogny force Spherical RPA with Gogny force J. Decharg and L.Sips, Nucl. Phys. A 407,1 (1983) J.P. Blaizot, J.F. Berger, J. Decharg, M. Girod, Nucl. Phys. A 591, 435 (1995) S. Pru, JF. Berger, PF. Bortignon, Eur. Phys. J. A 26, 25-32, (2005) Beyond mean field with QRPA RPA approaches are well adapted for describing giant resonances First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Approach limited to Spherical nuclei with no pairing Giant resonances in exotic nuclei: 100 Sn, 132 Sn, 78 Ni; S. Pru, J.F. Berger, and P.F. Bortignon, Eur. Phys. Jour. A 26, (2005) RPA in spherical symmetry Such study have shown the role of the consistence between mean field and RPA matrix. Dipole Monopole Quadrupole First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Axially-symmetric deformed QRPA Main features: Possibility to treat axially-symmetric deformed nuclei Pairing correlations consistently included Use of an unique nuclear force: finite range Gogny force -same interaction for all the nuclei -same interaction for ground state and excited states (self-consistency) essential features to treat consistently isotopic chains from drip line to drip line J K to calculate:for all QRPA states (K J) For example: J = 2 + In intrinsic frame We use rotational approximation and relations for 3j symbols Using time reversal symmetry, three independent calculations ( K = 0 +, 1 +, 2 + ) are needed. Restoration of rotational symmetry for deformed states First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru S. Pru and H. Goutte, Phys. Rev. C 77, (2008). IV Dipole Potential Energy Surfaces Potential Energy Surfaces K =0 - K =1 - J K K=0 K=1 First study with QRPA in axial symmetry First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Dipole response for Neon isotopes 20 Ne 22 Ne 24 Ne 26 Ne 28 Ne 18 Ne Increasing neutron number Low energy dipole resonances and shift to low energies Increasing of fragmentation 26 Ne : B(E1) = 0.49 0.16 e 2 fm 2 %STRK = 4.9 9 MeV J. Gibelin et al, PRL 101, (2008) B(E1)=0.173 e 2 fm MeV First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru M. Martini, S. Pru and M. Dupuis, Phys. Rev. C 83, (2011) Dipole response for Neon isotopes and N=16 isotones Increasing |N-Z| number : Low energy dipole resonances shift to low energies Increasing of fragmentation and collectivity PDR GDR PDR : piccola dipole resonance First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Multipolar responses for 238 U J K Heavy deformed nucleus massively parallel computation S. Pru et al, PRC 83, (2011) First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Photoneutron cross sections for Mo isotopes First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Photo-absorption cross sections for Mo isotopes First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Dipole electric and magnetic excitations for Zr isotopes E1 H. Utsunomiya et al, PRL 100, (2008) M1 E1 M1 H. Utsunomiya et al. (2008) First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Large scale calculation for photo-absorption We want to predict E1 strengths for all the nuclei. First we want to validate our approach by calculating E1 strengths for all the nuclei for which photo-absorption data exist. Because large part of data is related to odd A or odd-odd nuclei, we make the choice to calculate E1 strengths for all even-even nuclei for which data exist and for even-even nuclei in the neighbourhood of odd nuclei for which data exist. The strength of odd nuclei will be extrapolate/interpolate : for one odd A nucleus two even nuclei are needed; for one odd-odd nucleus four even-even nuclei are needed. Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Global trend : D1S versus D1M A few 100 keV overestimation of the D1S centroid energies with respect to D1M ones leads to a 0,2 shift of the EWSR (in TRK units). Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Impact of the deformation Small deformation Large deformation Oblate nuclei Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Comparison with experimental data One Lorentzian in RIPLTwo Lorentzians in RIPL Low energy parthigh energy part Systematic overestimation of the centroid energies : 2MeV D1M RIPL Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru To take into account complex configurations as well as coupling with phonons, the deformed QRPA strength S E1 (w) is folded with a Lorentzian function L(E,w) of width Semi-empirical broadening of the GDR Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Semi-empirical broadening of the GDR Paper to be submitted Model 0 Model 1 Model 2 RIPL First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Semi-empirical broadening of the GDR Model 0 Model 1 Model 2 RIPL Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Low energy dipole excitations Comparison of the QRPA low-energy E1 strength functions with experimental compilation for nuclei from 33 S up to 239 U at energies ranging from 4 to 8 MeV. Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru - ray strength functions predictions for exotic nuclei Paper to be submitted e.g. Sn isotopes First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru - ray strength functions predictions for exotic nuclei e.g. Sn isotopes Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru summary Fully self-consistent QRPA using the finite range Gogny force has been applied to spherical and axially-symmetric-deformed nuclei. 5DCH and QRPA approaches can complete each other a new hope: vibrational mass parameters through QRPA see F. LECHAFTOIS talk (collaboration with I. Deloncle CSNSM) IsoScalar-IsoVector mixing for low-lying dipole states in Ne isotopes and N=16 isotones. Self-consistent QRPA approach has been applied to the deformed nuclei up to 238 U. QRPA results successfully used in reaction models ; Systematic calculations are on the way Extension to odd A or odd-odd nuclei is in progress (collaboration with I. Deloncle CSNSM) First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru QRPA Formalism Particle-hole excitations: RPA 2 quasi-particles excitations: QRPA 2 p1/2 2 p3/2 1 f7/2 1 d3/2 2 s1/2 Fermi 1 d5/2 1 p1/2 1 p3/2 1 s1/2 26 Ne Neutrons HF levels Same interaction (Gogny) in HFB and QRPA p-h p-p Hartree-Fock Bogoliubov: , u, v QRPA: , X, Y Ground state properties Excited states properties h-h First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Axially-symmetric deformed QRPA Main features: Possibility to treat axially-symmetric deformed nuclei J K Use of an unique nuclear force: finite range Gogny force -same interaction for all the nuclei -same interaction for ground state and excited states (self-consistency) essential features to treat consistently isotopic chains from drip line to drip line Pairing correlations consistently included central density dependent spin-orbit finite range Gogny force (D1M, D1S) First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Spurious states treatment First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru (n, x n) cross section on 238 U Problem of underestimation of n emission cross section at high energy QRPA provides enough collective contribution M. Dupuis, S.Pru, E. Bauge and T. Kawano, 13th International Conference on Nuclear Reaction Mechanisms, Varenna 2012 CERN-Proceedings , p 95 Beyond the nuclear structure First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Size of the basis and 2 qp-energy cut-off impacts K = 0 - K = 1 - Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Dipole excitations and photoabsorption results Interpolation for odd nuclei Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Nuclear Masses Comparison with experimental data (2149 nuclei: Audi, Wapstra & Thibault 2003) r.m.s = MeV S. Goriely, S. Hilaire, M. Girod, S. Pru, PRL 102, (2009) Gogny D1M First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru 2qp energy Cut-off Energy shifts of the two main peaks of the B(E1) distribution predicted with D1M as a function of the atomic mass for 30 MeV cut-off and 60 MeV cut-off with respect to no cut-off (or very large one). Predictions. The full squares indicate calculations for which Nsh values are compatible with Table II. First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru We calculate E1 strength for all the nuclei for which photoabsorpion data exist. QRPA strength S E1 (w) is folded with a Lorentzian function with an energy shift deduced from GDR centroid. Dipole excitations and photoabsorption results [mb] 28 Si Exp. QRPA 60 Ni 70 Ge 74 Ge 76 Ge 80 Se 90 Zr 94 Zr 94 Mo 98 Mo 116 Sn 120 Sn 124 Te 128 Te 138 Ba 142 Ce 144 Nd 148 Nd 144 Sm 150 Sm 158 Gd 174 Yb 206 Pb 232 Th First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru Semi-empirical broadening of the GDR N Paper to be submitted First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru predicted neutron-capture cross section Impact on the predicted neutron-capture cross section of astrophysical interest First Gogny conference, TGCC December 2015 DAM, DIF, S. Pru spurious state IS GMR GQR IV GDR Monopole Dipole Quadrupole Octupole IV GMR High energy collective states: giant resonances Giant resonances are related to nuclear matter properties