Skip to main content
SpringerLink
Log in

Competition between few nucleon emission andγ-ray deexcitation for the reaction systems65Cu+87Rb and40Ar+110Pd

  • Nuclei
  • Published:
Zeitschrift für Physik A Atoms and Nuclei

Abstract

Bothγ-ray and neutron emission have been studied for the reaction systems65Cu(237MeV) +87Rb→152Dy* and40Ar(158MeV)+110Pd→150Gd*. By using a sum spectrometer in coincidence with neutron counters, Ge(Li) or Nal detectors, we have measured the totalγ-ray energy and the average totalγ-multiplicity distributions as well as the neutron spectra for various exit channels. These measurements provide strong evidence for thermal equilibrium in reactions involving a small number of emitted neutrons (i.e.87Rb(65Cu,n or 2n)) at rather high excitation energy (∼54MeV). This statistical emission of only a few neutrons is controlled by very strong y-ray competition: theγ-entry line is found not to be parallel to the yrast line. Instead the energy gap is about 8MeV for J∼27ħ and rises to at least 13MeV for J∼36ħ. There are some indications that the main part of the energy from this gap is removed by statisticalγ-ray cascades. The main features of the experimental data for both entrance channels are well reproduced by statistical model calculations with proper attention to the yrast line position and an adjustement of the dipoleγ-ray normalization coefficient. It is conceivable that the y-ray enhancement that we introduce may be related to a lack of knowledge of the absolute level densities at high energy and spin, or possibly to the presence of new or additional degrees of freedom that may enter into the competition between neutron andγ-ray emission.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Cabot, C., Gauvin, H., Le Beyec, Y., Delagrange, H., Dufour, J.P., Fleury, A., Llabador, Y., Alexander, J.M.: J. Phys. (Paris) Colloq. C10, (Suppl. au n∘12, Tome 41) C10–234 (1980)

    Google Scholar 

  2. Cabot, C., Gauvin, H., Le Beyec, Y., Delagrange, H., Dufour, J.P., Fleury, A., Llabador, Y., Alexander, J.M.: Nucl. Phys. A427, 173 (1984)

    Google Scholar 

  3. Delia Negra, S., Gauvin, H., Jungclas, H., Le Beyec, Y., Lefort, M.: Z. Phys. A —Atoms and Nuclei282, 65 (1977)

    Google Scholar 

  4. Cabot, C., Delia Negra, S., Gauvin, H., Le Beyec, Y., Lefort, M.: Proceedings of the International Conference on Nuclear Structure, Tokyo. Comm. 668 (1977)

  5. Cabot, C., Delia Negra, S., Gauvin, H., Delagrange, H., Dufour, J.P., Fleury, A.: Phys. Lett.96B, 55 (1980)

    Google Scholar 

  6. Cabot, C., Delia Negra, S., Gauvin, H., Le Beyec, Y., Lefort, M.: Annuaire de l'Inst. de Physique Nucléaire d'Orsay, p. R5 (1977)

  7. Kühn, W., Chowdhury, P., Janssens, R.V.F., Khoo, T.L., Haas, F., Kasagi, J., Ronningen, R.M.: Phys. Rev. Lett.51, 1858 (1983)

    Google Scholar 

  8. Haas, B., Duchêne, G., Beck, F.A., Gehringer, C., Merdinger, J.C., Nourredine, A., Rauch, V., Vivien, J.P., Barrette, J., Tobbeche, S., Bozek, E., Styczen, J., Keinonen, J., Dudek, J., Nazarewicz, W.: Phys. Rev. Lett.54, 398 (1985)

    Google Scholar 

  9. Nolan, P.J., Love, D.J.G., Kirwan, A., Unwin, D.J., Nelson, A.H., Twin, P.J., Garrett, J.D.: Phys. Rev. Lett.54, 2211 (1985)

    Google Scholar 

  10. Cabot, C., Gauvin, H., Sergolle, H., Aguer, P., Bastin, G., Thibaud, J.P., Patin, Y.: XXth International Winter Meeting on Nuclear Physics, Bormio, Vol.2, p. 436. Istituto di Fisica, Milano (1982)

    Google Scholar 

  11. - Orsay report IPNO-DRE-82-07 (1982)

  12. Cabot, C.: Thèse de Doctorat d'Etat, Université Paris XI. IPNO-T-83-02 (1982)

  13. Thibaud, J.P., Aguer, P., Bastin, G., Nguyen, L., Perrin, N., Sergolle, H., Gizon, J., Hubert, Ph., Villard, M.M.: Z. Phys. A — Atoms and Nuclei321, 275 (1985)

    Google Scholar 

  14. Nguyen, L.: Thèse de 3ème cycle, Université de Paris XI, 1982

  15. Körner, H.J., Willis, D.L., Roulet, C.P., Aguer, P., Ellegaard, C., Fossan, D.B., Habs, D., Neiman, N., Stephens, F.S., Diamond, R.M.: Phys. Rev. Lett.43, 490 (1979)

    Google Scholar 

  16. Nguyen, L.: to be suppressed

  17. Oblozinsky, P., Simon, R.S.: Nucl. Instrum. Methods223, 52 (1984)

    Google Scholar 

  18. Hillis, D.L., Garrett, J.D., Christensen, O., Fernandez, B., Hagemann, G.B., Herskind, B., Back, B.B., Folkmann, F.: Nucl. Phys. A325, 216 (1979)

    Google Scholar 

  19. Folkmann, F., Garrett, J.D., Hagemann, G.B., Harakeh, M.N., Herskind, B., Hillis, D.L., Ogaza, S., Emling, H., Grosse, E., Schwalm, D., Simon, R.S., Tjom, P.O.: Nucl. Phys. A361, 242 (1981)

    Google Scholar 

  20. Herskind, B.: International Conference of Nuclear Behaviour at High Angular Momentum. J. Phys. (Paris) C10, (Tome 41) 106 (1980)

    Google Scholar 

  21. Van Der Werf, S.Y.: Nucl. Instrum. Methods153, 221 (1978)

    Google Scholar 

  22. Habs, D., Stephens, F.S., Diamond, R.M.: Berkeley Report 3.79/130

  23. Aguer, P., Bastin, G., Peghaire, A., Thibaud, J.P., Perrin, N., Sergolle, H., Hubert, P.: Phys. Scr.24, 140 (1981)

    Google Scholar 

  24. Andersen, O., Bauer, R., Hagemann, G.B., Haibert, M.L., Herskind, B., Neiman, M., Oeschler, H., Ryde, H.: Nucl. Phys. A295, 163 (1978)

    Google Scholar 

  25. Jaaskelainen, M.: Research report n∘ 7/1983, Department of Physics, University of Jyvaskylä (May, 1983)

  26. Sie, S.H., Diamond, R.M., Newton, J.O., Leigh, J.R.: Nucl. Phys. A352, 279 (1981)

    Google Scholar 

  27. Sie, S.H., Newton, J.O., Leigh, J.R., Diamond, R.M.: Phys. Rev. Lett.46, 405 (1981)

    Google Scholar 

  28. Liotta, R., Sorensen, R.A.: Nucl. Phys. A297, 162 (1978)

    Google Scholar 

  29. Bertin, A., Frehaut, J.: Rapport CEA-R.4895 (1978)

  30. Drosg, M.: Nucl. Sci. Eng.67, 190 (1978)

    Google Scholar 

  31. Le Couteur, K.L., Lang, D.W.: Nucl. Phys.13, 32 (1959)

    Google Scholar 

  32. Geoffroy Young, K., Sarantites, D.G., Beene, J.R., Haibert, M.L., Hensley, D.C., Dayras, R.A., Barker, S.H.: Phys. Rev. C23, 2479 (1981)

    Google Scholar 

  33. Cabot, C., Delia Negra, S., Deprun, C., Gauvin, H.: Annuaire de l'Institut de Physique Nucléaire, Orsay, p. R11 (1980)

  34. Myers, W.D., Swiatecki, W.J.: Lawrence Radiation Laboratory, UCRL-11980 (1965)

  35. Simpson, J., Riley, M.A., Cresswell, J.R., Forsyth, P.D., Howe, D., Nyako, B.M., Sharpey-Schafer, J.F., Bacelar, J., Garrett, J.D., Hagemann, G.B., Herskind, B., Holm, A.: Phys. Rev. Lett.53, 648 (1984)

    Google Scholar 

  36. Deleplanque, M.A., Byrski, T., Diamond, R.M., Hübel, H., Stephens, F.S., Herskind, B., Bauer, R.: Phys. Rev. Lett.41, 1105 (1978)

    Google Scholar 

  37. Hübel, H., Diamond, R.M., Stephens, F.S., Herskind, B., Bauer, R.: Z. Phys. A —Atoms and Nuclei297, 237 (1980)

    Google Scholar 

  38. Khoo, T.L., Smither, R.K., Haas, B., Hausser, O., Andrews, H.R., Horn, D., Ward, D.: Phys. Rev. Lett.41, 1027 (1978)

    Google Scholar 

  39. Haas, B., Andrews, H.R., Hausser, O., Morn, D., Sharpey-Schafer, J.F., Taras, P., Trautman, W., Ward, D., Khoo, T.L., Smither, R.K.: Phys. Lett.84B, 178 (1979)

    Google Scholar 

  40. Khoo, T.L.: In: Proceedings of the Nobel Symposium on Nuclei at very High spin, Orenäs, Sweden, June 1980

  41. Bohr, A., Mottelson, B.R.: Nuclear structure. Vol.2. New York: Benjamin 1975

    Google Scholar 

  42. Cohen, S., Plasil, F., Swiatecki, W.J.: Ann. Phys. (NY)82, 557 (1974)

    Google Scholar 

  43. Williams, D.C., Thomas, T.D.: Nucl. Phys. A92, 1 (1967)

    Google Scholar 

  44. Vaz, L.C., Alexander, J.M., Satchler, G.R.: Phys. Rep. C69, n∘5, 373 (1981)

    Google Scholar 

  45. Jahnke, U., Rossner, H.H., Hilscher, D., Holub, E.: Phys. Rev. Lett.48, 17 (1981)

    Google Scholar 

  46. Cabot, C., Delia Negra, S., Deprun, C., Gauvin, H.: Annuaire de l'Institut de Physique Nucléaire d'Orsay, p. R7 (1981)

  47. Cabot, C., Gauvin, H., Delagrange, H.: (to be published)

  48. Grover, J.R., Gilat, J.: Phys. Rev.157, 802, 814 (1967)

    Google Scholar 

  49. Gilbert, A., Cameron, A.G.W.: Can. J. Phys.43, 1446 (1965)

    Google Scholar 

  50. Beckerman, M., Blann, M.: Phys. Rev. Lett.38, 272 (1977)

    Google Scholar 

  51. Beckerman, M., Blann, M.: Phys. Rev. C17, 1615 (1978)

    Google Scholar 

  52. Plasil, F.: J. Phys. (Paris). Colloq. C10, (Suppl. au n∘12, Tome 41) C10 (1980)

    Google Scholar 

  53. Plasil, F., Ferguson, R.L., Hahn, R.L., Obenshain, F.E., Pleasonton, F., Young, G.R.: Phys. Rev. Lett.45, 333 (1980)

    Google Scholar 

  54. Von Oertzen, W., Fuchs, H., Gamp, A., Homeyer, H., Jahnke, U., Jacmart, J.C.: Z. Phys. A —Atoms and Nuclei298, 207 (1980)

    Google Scholar 

  55. Leigh, J.R., Hinde, D.J., Newton, J.O., Galster, W., Sie, S.H.: Phys. Rev. Lett.48, 527 (1982)

    Google Scholar 

  56. Delagrange, H.: Ann. Phys. (Paris)3, 193 (1982)

    Google Scholar 

  57. Blann, M., Komoto, T.T.: Phys. Rev. C26, 2, 472 (1982)

    Google Scholar 

  58. Grangé, P., Jin-Qing, L., Weidenmüller, H.A.: Phys. Rev. C27, 2063 (1983)

    Google Scholar 

  59. Newton, J.O., Herskind, B., Diamond, R.M., Dines, E.L., Draper, J.E., Lindenberger, K.H., Schuck, C., Shih, S., Stephens, F.S.: Phys. Rev. Lett.46, 1383 (1981)

    Google Scholar 

  60. Lynn, J.E.: Theory of neutron resonance reactions, p. 321. Oxford: Clarendon 1968

    Google Scholar 

  61. Gaardhoje, J.J.: XXth International Winter Meeting on Nuclear Physics, Bormio. Vol.1, p. 107. Istituto di Fisica, Milano (1982)

    Google Scholar 

  62. Barrette, J., Sandorfi, A.M.: Comm. Nucl. Part. Phys.12 (n∘2), 57 (1983)

    Google Scholar 

  63. Garrett, J.D.: Private communication

  64. Cormier, T.M., Cormier, P.M., Herman, M., Nicolis, N.G., Stwertka, P.M.: Phys. Rev. Lett.51, 542 (1983)

    Google Scholar 

  65. Landowne, S., Dasso, C.H.: Phys. Lett.138B, 32 (1984)

    Google Scholar 

  66. Gilat, J.: Brookhaven National Laboratory report BNL50246 (1970) unpublished

  67. Delagrange, H., Fleury, A., Alexander, J.M.: Phys. Rev. C16, 706 (1977)

    Google Scholar 

  68. Blatt, J.M., Weisskopf, V.F.: Theoretical nuclear physics. New York: John Wiley 1962

    Google Scholar 

  69. Goldberg, M.D., Mughabghab, S.F., Purohit, S.N., Magurno, B.A., May, V.M.: BNL report325, 2th Edn. (1966)

  70. Gilat, J., Fleury, A., Delagrange, H., Alexander, J.M.: Phys. Rev. C16, 694 (1977)

    Google Scholar 

  71. Bollinger, L.M., Thomas, G.E.: Phys. Rev. C2, 1951 (1970)

    Google Scholar 

  72. Perey, C.M., Perey, F.G.: At. Data Nucl. Data Tables17, 1–101 (1976)

    Google Scholar 

  73. Satchler, G.R.: Nucl. Phys.70, 177 (1965)

    Google Scholar 

Download references

Author information

Author notes

  1. H. Delagrange

    Present address: G.A.N.I.L., B.P. 5027, F-14021, Caen Cedex, France

Authors and Affiliations

  1. Institut de Physique Nucléaire, Orsay, France

    C. Cabot, H. Gauvin & H. Sergolle

  2. C.S.N.S.M., Orsay, France

    P. Aguer, G. Bastin & J. P. Thibaud

  3. C.E.N.B.G., Gradignan, France

    H. Delagrange

  4. Centre d'Etudes Nucléaires de Bruyères le Châtel, Bruyères le Châtel, France

    Y. Patin

Authors
  1. C. Cabot
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. H. Gauvin
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. H. Sergolle
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. P. Aguer
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. G. Bastin
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. J. P. Thibaud
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. H. Delagrange
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Y. Patin
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

We are grateful to the ALICE staff for providing excellent beams, and to the authors of Ref. 5 as well as Dr. C. Roulet for their help in some measurements. We are indebted to Prof. J.D. Garrett for making available the modified version of the GROGI-2 code used in Copenhagen. We also wish to thank Dr. J. Barrette and Prof. J.M. Alexander for stimulating discussions and critical reading of the manuscript.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Cabot, C., Gauvin, H., Sergolle, H. et al. Competition between few nucleon emission andγ-ray deexcitation for the reaction systems65Cu+87Rb and40Ar+110Pd. Z Physik A 322, 393–414 (1985). https://doi.org/10.1007/BF01412074

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01412074

PACS

Search

Navigation