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Nuclear theoretical physics in IFIN-HH. Departments: Department of Theoretical Physics (DTP) Department of Nuclear Physics (DNP). 1. Marilena Avrigeanu ( DNP ) 2. Vlad Avrigeanu ( DNP ) 3. Virgil Baran (DTP) 4. Iosif Bulboaca (DTP) 5. Florin Carstoiu (DTP) 6. Doru Delion (DTP)
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Nuclear theoretical physicsin IFIN-HH Departments: Department of Theoretical Physics (DTP) Department of Nuclear Physics (DNP)
1. Marilena Avrigeanu (DNP) 2. Vlad Avrigeanu (DNP) 3. Virgil Baran (DTP) 4. Iosif Bulboaca (DTP) 5. Florin Carstoiu (DTP) 6. Doru Delion (DTP) 7. Radu Gherghescu (DTP) 8. Nicolae Grama (DTP) 9. Serban Misicu (DTP) 10. Mihai Mirea (DTP) 11. Alexandra Petrovici (DNP) 12. Dorin Poenaru (DTP) 13. Adriana Raduta (DNP) 14. Alexandru Raduta (DTP) 15. Apolodor Raduta (DTP) 16. Cristian Raduta (DTP) 17. Margarit Rizea (DTP) 18. Nicolae Sandulescu (DTP) 19. Ion Silisteanu (DTP) 20. Sabin Stoica (DTP) 21. Ioan Ursu (DTP) 22. Nicolae Zamfir (DNP) Researchers:
Papers (2003-2007): Phys. Rev. C 88 Phys. Rev. Lett. 4 Nucl. Phys. A 35 J. Phys. G 11 Eur. Phys. J. A 13 Eurphys. Lett. 2 Phys. Lett. B 7 Phys. Rep. 2 Int. J. Mod. Phys. E 8 Prog. Part. Nucl. Phys. 1 TOTAL 171
International cooperations: Universities: Wien (Austria) Gent, Leuven (Belgium) Jyvaskyla (Finland) Bordeaux, Nice, Strasbourg (France) Berlin, Frankfurt/Main, Heidelberg, Julich, Koln, Tuebingen (Germany), Catania, Napoli, Padova, Pisa (Italy) Delaware, Iowa, Michigan, Texas A&M, Yale (USA) Institutes: The Niels Bohr Institute, Copenhagen (Denmark) Laboratoire de Physique Corpusculaire, Caen (France) Institut de Physique Nucleaire, Orsay (France) Institut de Recherches Subatomiques, Strasbourg (France) Max-Planck Institut, Heidelberg (Germany) Institut fur Kernphysik, Julich (Germany) Institute of Nuclear Research, Debrecen (Hungary) Joint Institute of Nuclear Research, Dubna (Russia) Instituto de Estructura de la Materia, Madrid (Spain) Royal Institute of Technology, Stockholm (Sweden) Argonne National Laboratory (USA) Lawrence Livermore National Laboratory (USA) Oak Ridge National Laboratory (USA)
Nuclear structure: Hallo nuclei Nuclei close to drip lines Superheavy nuclei Multi-phonon states Giant resonances Nuclear processes: Exotic decays Binary and ternary fission Shape coexistence Phase transitions Nuclear fragmentation Phenomena: Astrophysics: Neutron stars Neutrino physics Nuclear reactions
General theoretical frameworkis the optimal approach: find an effective Hamiltonian Ĥ& the model space ψ to solve the evolution equation iħ∂tψ=Ĥψ in order to minimize the distance between expectation values of observables Ôk and experimental data Ok ∑k|<ψ|Ôk|ψ>-Ok|2=min
Phenomenological (collective coordinates): Double Folding Approach Coupled Channels Method Coherent State Model Interacting Boson Model Statistical Method Glauber Model Microscopic (nucleonic coordinates): Large Scale Shell Model Two Center Shell Model Projected HFB (VAMPIR) Finite temperature HFB Coupling with continuum Extensions of RPA Methods:
Nuclear potentials for deuteron scattering Semi-microscopic OMP (solid), global parameter of Lohr-Haeberly (dashed), Daehnick et al. (dot-dashed). For higher energies: Paris effective NN interaction M3Y (solid), BDM3Y (dashed), DDM3Y (dot-dashed) (M. Avrigeanu,, W. von Oertzen, A. Obreja, F.L. Roman, and V. Avrigeanu, Int. Conf. on Nuclear Data for Science and Technology, April 22-27, 2007, Nice,France)
Nuclear potentials for alpha scattering α-scattering distributions of Baye et al., M3Y-Reid (solid), and M3Y-Paris (dashed) effective NN interactions, in comparison with experimental data. M. Avrigeanu, W.von Oertzen, A.J.M. Plompen and V. Avrigeanu, Nucl. Phys. A723, (2003) 104.
Proton rich emittersReduced half-lives (without centrifugal barrier)versus the Coulomb parameter D.S.Delion, R.J.Liotta, R.Wyss, Phys.Lett. 96, 072501 (2006)
Correlation between the mean field deformationand reduced width (without Coulomb+centrifugal barriers)
Shell Model calculations 1) No Core Shell Model Calculations (NCSM) 2) Shell Model Calculations (SM) with modern NN interactions NCSM- first calculations for the A=48 mass nuclei (Ca, Sc, Ti) Limited goals: - study of different correlations and effective interactions in this region • preparation for future larger scale NCSM calculations J.P. Vary,…, A. G. Negoita,S. Stoica, et al., Eur. Phys. J. A 25, 475 (2005). J.P. Vary, S. Stoica, S. Popescu, P. Navratil, Phys. Rev. C2007 (in press) J.P. Vary, A. Negoita, S. Stoica, Phys. Rev. C (submitted)
Projected HFB before variationwithin VAMPIR approaches -Coexistence phenomena in the A=70 region -Nuclear structure near N=Z line (pn pairing) -Isospin breaking in superallowed Fermi β-decay -Effective interaction for A=60-90 nuclei A.Petrovici, et. al., Nucl. Phys. A728, 396 (2003), A747, 44 (2005), A770, 107 (2006); J. Phys. G32, 583 (2006); Eur. Phys. J. A28, 19 (2006).
Double beta (ββ) decay andneutrino mass two-neutrino ββ decay mode: (A, Z) -> (A, Z + 2) + 2 e- + 2 neutrinoless ββdecay mode: (A, Z) -> (A, Z + 2) + 2 e- -decay experiments are the only that have the potential to determine whether is a Majorana or a Dirac particle. Nuclear structure methods Quasi-Particle RPA ≡ QRPA→ higher QRPA Nuclear Shell Model
Higher-QRPA A.A.Raduta, A. Faessler, S. Stoica, Nucl. Phys. A534, 149 (1991). S. Stoica, H.V. Klapdor-Kleingrothaus, Nucl. Phys. A694, 269 (2001) S. Stoica, Iad. Fiz., 2004, 67, №9, 1–8 S. Stoica, Mod. Phys. Lett. 19, 165 (2004)
Exotic nuclei near the drip linesOne nucleon removal reactions using Glauber approachF. Carstoiu, et al, Phys. Rev. C74, 014605 (2006)
Pairing correlations in Nuclei Close to Drip Lines Treatment of continuum in BCS, HFB and QRPA models • Resonant states • giant halos • Collective modes giant pairing vibration N.Sandulescu, L.S.Geng, H. Toki, PRC68(2003) E. Khan, N. Sandulescu, Nguyen Van Giai, Phys. Rev. C66 (2002)
Dynamical single particle effects on fission cross-sectionresonant structure M. Mirea, L. Tassan-Got, C. Stephan, C.O. Bacri, R.C. Bobulescu, Europhys. Lett. 73, 705 (2006)
Superheavy nuclei -A new method to obtain superheavy nuclei by using high-spin two quasi-paricle isomeric states D.S. Delion, R. Wyss, R.J. Liotta, Phys.Rev. C76, 044301 (2007) -A semi-empirical relationship for α-decay half-lives of nuclei, taking into account the shell effects D. N. Poenaru, I. H. Plonski, W. Greiner, Phys. Rev. C74, 014312 (2006) D. N. Poenaru, R. A. Gherghescu, N. Carjan, Europhys. Lett. 77, 62001 (2007) -A new method to obtain the saddle-point shapes of superheavy nuclei by solving an integro-differential equation D. N. Poenaru, R. A. Gherghescu, W. Greiner, Nucl. Phys. A 747,182-205 (2005) D. N. Poenaru, R. A. Gherghescu, W. Greiner, Eur. Phys. J. A 24,355-359(2005)
Quantum phase transitionsin mesoscopic systems Casten triangle for the IBA Hamiltonian: H=ε[(1-ξ)nd- ξ/(4N)Q.Q
New order parameters for phase transitions F. Iachello, N.V. Zamfir, Phys.Rev.Lett. 92, 212501 (2004) ν1=<01|nd|01>/N; ν2=[<02|nd|02>-<01|nd|01>]/N
Nuclear fragmentation:liquid-gas phase transition? The rotation of the order parameter under Coulomb interaction F. Gulminelli, Ph. Chomaz, Al. H. Raduta, Ad. R. Raduta, Phys. Rev. Lett. 91, 202701 (2003)
Nuclei beyond drip line: inner crust of neutron stars nuclei + unbound neutrons What are the effects of nuclear superfluidity on cooling time of neutron stars ? Microscopic treatment Enuc= ESkyrme+ Epair [ r,k] • HFB at finite temperature • QRPA: collective states N. Sandulescu, PRC70 , 025801 (2004) E.Khan, N.Sandulescu, N. Van Giai, PRC71, 042801(R) (2005)
Efficient procedures to solve mathematical equations in nuclear physics -High order methods for solving the radial and time-dependent Schrodinger equation V. Ledoux, M. Rizea, L. Ixaru, G. Vanden Berghe, M. Van Daele, Comp. Phys. Comm. 175(6), 424-439 (2006) -Improved numerical boundary conditions for Schrodinger-type equations M. Rizea in Lectures Series on Computer and Computational Sciences, Vol.7, Brill Academic Publishers, Netherlands, 464-468 (2006) -Solution of the two-dimensional Schrodinger equation by functionally fitted finite difference formulae V. Ledoux, L. Ixaru, M. Rizea, M. Van Daele, G. Vanden Berghe, Comp. Phys. Comm. 175(9), 612-619 (2006) Applications: -Proton emission from spherical and deformed nuclei N. Carjan, M. Rizea, D. Strottman, Comp. Phys. Comm. 173, 41-60 (2005) -Scission neutron emission during nuclear fission N. Carjan, M. Rizea, Int. Nucl. Phys. Conference, INPC 2007, Tokyo, Japan, June 3-8, 2007
Research directions -Improve effective nuclear potentials by using: hallo nuclei data fit of scattering data no core shell model and projected HFB calculations -Investigate the proton/neutron rich and superheavy nuclei -Search for shellstability islands -Improve the knowledge on fission -Investigate the equation of state by using fragmentation -Obtain a consistent picture of neutrinos by: improving matrix elements of ββ-decay determining the dominant mechanism of 0νββ-decay combining neutrino oscillations and cosmologic data -Increase the efficiency of numerical algorithms