1 / 19

Erice, 16. - 24. September 2006

Erice, 16. - 24. September 2006 School on nuclear physics ‘`Radioactive Beams, Nuclear Dynamics and Nuclear Astro Physics‘. Theory of Pygmy Dipole Resonances in Exotic Nuclei. N. Tsoneva, H. Lenske. Institut für Theoretische Physik, Universität Giessen, Germany.

manchu
Télécharger la présentation

Erice, 16. - 24. September 2006

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Erice, 16. - 24. September 2006 School on nuclear physics ‘`Radioactive Beams, Nuclear Dynamics and Nuclear Astro Physics‘ Theory of Pygmy Dipole Resonances in Exotic Nuclei N. Tsoneva, H. Lenske Institut für Theoretische Physik, Universität Giessen, Germany

  2. Electric Dipole Response of the Nucleus A. Zilges et al., ISNSP, Götingen, 2001

  3. The Quasiparticle-Phonon Model V. G. Soloviev: Quasiparticles and Phonons, 1989

  4. Ground state properties of Sn isotopes F. Hofmann and H. Lenske, Phys. Rev. C 57 (1998) 2281. N. Tsoneva, H. Lenske, Ch. Stoyanov, Phys. Lett. B 586 (2004) 213.

  5. Calculation of ground state densities in Sn isotopes

  6. Calculation of ground state densities in Sn isotopes Radial distance (fm)

  7. The wave function

  8. QMP calculations of dipole excitations below the particle threshold in comparison with experimental data / S. Volz et al., Nucl. Phys. Ain press /.

  9. QRPA calculations of the total PDR strength (E*=0-8 MeV) in N=82 isotones A possible connection between the total PDR strength and the neutron skin thickness • Proton number increasing • Neutron skin decreasing S. Volz et al., Nucl. Phys. A, in press.

  10. The Dipole Response in Sn Isotopes PDR PDR PDR

  11. The transition density definition

  12. Calculations of one-phonon dipole transition densities in Sn isotopes

  13. One-phonon dipole transition densities in 100Sn

  14. QRPA calculations of the total PDR strength in Z=50 Sn nuclei A possible connection between the total PDR strength and the neutron skin thickness Exp. in Sn-116 and Sn-124: K. Govaert et al, Phys. Rev. C 57 (1998) 2229. Exp. in Sn-112, B. Ozel et al, private communications.

  15. Conclusions and outlook • The analysis of the corresponding neutron and proton transition densities in the mass region 110Sn-132Sn indicates almost pure neutron oscillations at the nuclear surface such that a PDR can be identified. • A close correlation between the total PDR strength and the size of the neutron skin is found. • The transition densities act as clear theoretical indicators characterizing the new quality of the PDR mode as a distinct and unique excitation, different from the well known GDR. • An interesting result is the observation that the neutron PDR strength in Z=50 nuclei changes gradually and smoothly with the neutron number and in 110Sn it completely vanishes. For the semimagic nuclei 100Sn,102Sn and 104Sn a proton PDR has been identified. • The calculations are compared to available data from photon scattering experiments for a number of Sn isotopes and members of the N=82 isotonic chain. A good agreement is obtained.

  16. Thank you for your attention !

  17. QRPA calculations of low-energy dipole states in N=82 nuclei S. Volz et al., Nucl. Phys. A, in press.

  18. Proton PDR states in Sn isotopes

  19. Structure and transitions probabilities of PDR states in Sn isotopes

More Related