Advertisement

Physics of Atomic Nuclei

, Volume 69, Issue 8, pp 1345–1352 | Cite as

Collective excitations in the unitary correlation operator method and relativistic QRPA studies of exotic nuclei

  • N. Paar
  • P. Papakonstantinou
  • H. Hergert
  • R. Roth
Proceedings of the National Conference on Nuclear Physics “Frontiers in the Physics of Nucleus” St. Petersburg State University, Russia June 28–July 1, 2005 Exotic Nuclei and Fundamental Interactions
  • 47 Downloads

Abstract

The collective excitation phenomena in atomic nuclei are studied in two different formulations of the random-phase approximation (RPA): (i) RPA based on correlated realistic nucleon-nucleon interactions constructed within the unitary correlation operator method (UCOM) and (ii) relativistic RPA derived from effective Lagrangians with density-dependent meson-exchange interactions. The former includes the dominant interaction-induced short-range central and tensor correlations by means of unitary transformation. It is shown that UCOM-RPA correlations induced by collective nuclear vibrations recover a part of the residual long-range correlations that are not explicitly included in the UCOM Hartree-Fock ground state. Both RPA models are employed in studies of the isoscalar giant monopole resonance in closed-shell nuclei across the nuclide chart, with an emphasis on the sensitivity of its properties on the constraints for the range of the UCOM correlation functions. Within the relativistic quasiparticle RPA (RQRPA) based on the relativistic Hartree-Bogolyubov model, the occurrence of pronounced low-lying dipole excitations is predicted in nuclei towards the proton drip line. From the analysis of the transition densities and the structure of the RQRPA amplitudes, it is shown that these states correspond to the proton pygmy dipole resonance.

PACS numbers

24.30.Cz 21.60.Jz 13.75.Cz 21.60.-n 21.30.-x 21.30.Fe 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    D. Vautherin and D. M. Brink, Phys. Rev. C 5, 626 (1972).CrossRefADSGoogle Scholar
  2. 2.
    J. Dechargé and D. Gogny, Phys. Rev. C 21, 1568 (1980).CrossRefADSGoogle Scholar
  3. 3.
    D. Vretenar, A. V. Afanasjev, G. A. Lalazissis, and P. Ring, Phys. Rep. 409, 101 (2005).CrossRefADSGoogle Scholar
  4. 4.
    R. B. Wiringa, V. Stoks, and R. Schiavilla, Phys. Rev. C 51, 38 (1995).CrossRefADSGoogle Scholar
  5. 5.
    R. Machleidt, Phys. Rev. C 63, 024001 (2001).Google Scholar
  6. 6.
    D. R. Entem and R. Machleidt, Phys. Lett. B 524, 93 (2002).CrossRefADSGoogle Scholar
  7. 7.
    S. C. Pieper, R. B. Wiringa, and J. Carlson, Phys. Rev. C 70, 054325 (2004).Google Scholar
  8. 8.
    P. Navrátil, J. P. Vary, and B. R. Barrett, Phys. Rev. C 62, 054311 (2000).Google Scholar
  9. 9.
    S. C. Pieper et al., Phys. Rev. C 64, 014001 (2001).Google Scholar
  10. 10.
    E. Epelbaum et al., Phys. Rev. C 66, 064001 (2002).Google Scholar
  11. 11.
    H. Feldmeier, T. Neff, R. Roth, and J. Schnack, Nucl. Phys. A 632, 61 (1998).CrossRefADSGoogle Scholar
  12. 12.
    T. Neff and H. Feldmeier, Nucl. Phys. A 713, 311(2003).zbMATHCrossRefADSGoogle Scholar
  13. 13.
    R. Roth, T. Neff, H. Hergert, and H. Feldmeier, Nucl. Phys. A 745, 3 (2004).CrossRefADSGoogle Scholar
  14. 14.
    R. Roth, H. Hergert, P. Papakonstantinou, et al., Phys. Rev. C 72, 034002 (2005).Google Scholar
  15. 15.
    S. K. Bogner, T. T. S. Kuo, and A. Schwenk, Phys. Rep. 386, 1 (2003).CrossRefADSGoogle Scholar
  16. 16.
    D. J. Rowe, Nuclear Collective Motion (Methuen, London, 1970).Google Scholar
  17. 17.
    P.-G. Reinhard and J. Friedrich, Z. Phys. A 321, 619 (1985).CrossRefGoogle Scholar
  18. 18.
    M. Matsuo, Nucl. Phys. A 696, 371 (2001).CrossRefADSMathSciNetGoogle Scholar
  19. 19.
    J. Terasaki, J. Engel, M. Bender, et al., Phys. Rev. C 71, 034310 (2005).Google Scholar
  20. 20.
    D. Sarchi, P. F. Bortignon, and G. Coló, Phys. Lett. B 601, 27 (2004).CrossRefADSGoogle Scholar
  21. 21.
    N. Paar, P. Ring, T. Nikšić, and D. Vretenar, Phys. Rev. C 67, 034312 (2003).Google Scholar
  22. 22.
    L. G. Cao and Z. Y. Ma, Phys. Rev. C 71, 034305 (2005).Google Scholar
  23. 23.
    D. Vretenar, N. Paar, P. Ring, and G. A. Lalazissis, Nucl. Phys. A 692, 496 (2001).CrossRefADSGoogle Scholar
  24. 24.
    N. Paar, D. Vretenar, and P. Ring, Phys. Rev. Lett. 94, 182501 (2005).Google Scholar
  25. 25.
    A. Leistenschneider et al., Phys. Rev. Lett. 86, 5442 (2001).CrossRefADSGoogle Scholar
  26. 26.
    L. Coraggio et al., Phys. Rev. C 68, 034320 (2003).Google Scholar
  27. 27.
    V. I. Isakov et al., Eur. Phys. J. A 14, 29 (2002).ADSGoogle Scholar
  28. 28.
    G. A. Lalazissis, J. König, and P. Ring, Phys. Rev. C 55, 540 (1997).CrossRefADSGoogle Scholar
  29. 29.
    H. Esbensen and G. F. Bertsch, Phys. Rev. C 28, 355 (1983).CrossRefADSGoogle Scholar
  30. 30.
    G. Audi and A. Wapstra, Nucl. Phys. A 595, 409 (1995).CrossRefADSGoogle Scholar
  31. 31.
    N. Ullah and D. J. Rowe, Phys. Rev. 188, 1640 (1969).CrossRefADSGoogle Scholar
  32. 32.
    T. Nikšić, D. Vretenar, P. Finelli, and P. Ring, Phys. Rev. C 66, 024306 (2002).Google Scholar
  33. 33.
    T. Nikšić, D. Vretenar, and P. Ring, Phys. Rev. C 66, 064302 (2002).Google Scholar
  34. 34.
    S. Drożdż, S. Nishizaki, J. Speth, and J. Wambach, Phys. Rep. 197, 1 (1990).CrossRefADSGoogle Scholar
  35. 35.
    D. H. Youngblood, H. L. Clark, and Y.-W. Lui, Phys. Rev. Lett. 82, 691 (1999).CrossRefADSGoogle Scholar
  36. 36.
    S. Shlomo and D. H. Youngblood, Phys. Rev. C 47, 529 (1993).CrossRefADSGoogle Scholar
  37. 37.
    M. M. Sharma and M. N. Harakeh, Phys. Rev. C 38, 2562 (1988).CrossRefADSGoogle Scholar
  38. 38.
    Y. Suzuki, K. Ikeda, and H. Sato, Prog. Theor. Phys. 83, 180 (1990).CrossRefADSGoogle Scholar
  39. 39.
    N. Paar, T. Nikšić, D. Vretenar, and P. Ring, Phys. Lett. B 606, 288 (2005).CrossRefADSGoogle Scholar
  40. 40.
    N. Paar, T. Nikšić, D. Vretenar, and P. Ring, Int. J. Mod. Phys. E 14, 1 (2005).CrossRefGoogle Scholar
  41. 41.
    N. Paar, P. Papakonstantinou, V. Yu. Ponomarev, and J. Wambach, Phys. Latt. B 624, 195 (2005).CrossRefADSGoogle Scholar
  42. 42.
    N. Paar, T. Nikšić, D. Vretenar, and P. Ring, Phys. Rev. C 69, 054303 (2004).Google Scholar

Copyright information

© Pleiades Publishing, Inc. 2006

Authors and Affiliations

  • N. Paar
    • 1
  • P. Papakonstantinou
    • 1
  • H. Hergert
    • 1
  • R. Roth
    • 1
  1. 1.Institut für KernphysikTechnische Universität DarmstadtDarmstadtGermany

Personalised recommendations