Advertisement

Zeitschrift für Physik A Hadrons and Nuclei

, Volume 357, Issue 2, pp 193–205 | Cite as

Excitation energy division in 51V + 197Au collisions at and near the barrier

  • P. Klein
  • J. V. Kratz
  • M. K. Gober
  • H. P. Zimmermann
  • W. Brüchle
  • W. Reisdorf
  • M. Schädel
Article

Abstract

Mass- and charge-yield distributions for 19 < Z < 84 were determined radiochemically for the binary collision products of 51V + 197Au collisions at a bombarding energy corresponding exactly to the Bass-model barrier, E cm = B, and at E cm = B + 25 MeV. The average excitation energies as a function of Z are determined by comparing the centroids of the experimental, secondary mass distributions for given values of Z with the calculated primary centroids from minimization of the potential energy of the di-nuclear system, i.e. from the missing masses. At the barrier, in striking contrast to a thermal equilibrium, we find an extreme donor-acceptor asymmetry in the excitation-energy division reminiscent of the “sawtooth” phenomenon in low-energy nuclear fission. Here, the excitation energy sharing is apparently dominated by shape fluctuations at scission. At the slightly higher bombarding energy, E cm = B + 25 MeV, we observe a rapid change toward equipartition of the excitation energy indicating that, here, the excitation energy division due to shape fluctuations is already covered up by the dissipative exchange of nucleons. Also, the balance of integral cross sections for fusion fission, deep-inelastic scattering, and quasi fission is investigated and is shown to contain important information about the dynamical evolution of the 51V + 197Au system after having passed the entrance channel barrier.

PACS

25.70.Lm 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Töke, J., Schröder, W.U.: Annu. Rev. Nucl. Part. Sci. 42, 401 (1992)CrossRefGoogle Scholar
  2. 2.
    Brosa, U., Grossmann, S., Müller, A.: Phys. Rep. 197, 167 (1990)ADSCrossRefGoogle Scholar
  3. 3.
    Randrup, J.: Nucl. Phys. A307, 319 (1978), Nucl. Phys. A327, 490 (1979); Nucl. Phys. A383, 468 (1982)ADSCrossRefGoogle Scholar
  4. 4.
    Gäggeler, H., Brüchle, W., Brügger, M., Schädel, M., Sümmerer, K., Wirth, G., Kratz, J.V., Lerch, M., Blaich, Th., Herrmann, G., Hildebrand, N., Trautmann, N., Lee, D., Moody, K.J., Gregorich, K.E., Welch, R.B., Seaborg, G.T., Hoffman, D.C., Daniels, W.R., Fowler, M.M., von Gunten, H.R.: Phys. Rev. C33, 1983 (1986)ADSGoogle Scholar
  5. 5.
    Keller, H., Bellwied, R., Lützenkirchen, K., Kratz, J.V., Brüchle, W., Gäggeler, H., Moody, K.J., Schädel, M., Wirth, G.: Z. Phys. A328, 255 (1987)ADSGoogle Scholar
  6. 6.
    Scherer, U.W., Brüchle, W., Brügger, M., Frink, C., Gäggeler, H., Herrmann, G., Kratz, J.V., Moody, K.J., Schädel, M., Sümmerer, K., Trautmann, N., Wirth, G.: Z. Phys. A335, 421 (1990)ADSGoogle Scholar
  7. 7.
    Funke, F., Kratz, J.V., Trautmann, N., Wiehl, N., Wirth, G., Brüchle, W., Fan Wo, Sümmerer, K.: Z. Phys. A340, 303 (1991)ADSGoogle Scholar
  8. 8.
    Reisdorf, W., Kratz, J.V., Bellwied, R., Brüchle, W., Keller, H., Lützenkirchen, K., Schädel, M., Sümmerer, K.: Z. Phys. A342, 411 (1992)ADSGoogle Scholar
  9. 9.
    Chatterjee, M.B., Baldwin, S.P., Huizenga, J.R., Pade, D., Quednau, B.M., Schroder, W.U., Szabo, B.M., Töke, J.: Phys. Rev. C44, R2249 (1991)ADSGoogle Scholar
  10. 10.
    Beier, G., Friese, J., Henning, W., Kienle, P., Körner, H.J., Wanger, W., Mayer, W.A., Mayer, W.: Z. Phys. A336, 217 (1990)ADSGoogle Scholar
  11. 11.
    Kratz, J.V.: Radiochim. Acta 70/71, 147 (1995)Google Scholar
  12. 12.
    Klein, P.: Doctoral thesis, Universität Mainz 1993, and GSI report 93-37Google Scholar
  13. 13.
    Gober, M.K.: Doctoral thesis, Uniersität Mainz 1992Google Scholar
  14. 14.
    Kratz, J.V., Brüchle, W., Franz, G., Schädel, M., Warnecke, I., Wirth, G., Weis, M.: Nucl. Phys. A332, 477 (1979)ADSCrossRefGoogle Scholar
  15. 15.
    Lützenkirchen, K., Kratz, J.V., Brüchle, W., Gäggeler, H., Sümmerer, K., Wirth, G.: Z. Phys. A317, 55 (1984)ADSCrossRefGoogle Scholar
  16. 16.
    Poitou, J., Lucas, R., Kratz, J. V., Brüchle, W., Gäggeler, H., Schädel, M., Wirth, G.: Phys. Lett. 88B, 69 (1979)ADSCrossRefGoogle Scholar
  17. 17.
    Kratz, J.V., Poitou, J., Brüchle, W., Gäggeler, H., Schädel, M., Wirth, G., Lucas, R.: Nucl. Phys. A357, 437 (1981)ADSCrossRefGoogle Scholar
  18. 18.
    Myers, W.D., Swiatecki, W.J.: Nucl. Phys. 81, 1 (1996)CrossRefGoogle Scholar
  19. 19.
    Dortrovsky, I., Fraenkel, Z., Friedlander, G.: Phys. Rev. 116, 683 (1959)ADSCrossRefGoogle Scholar
  20. 20.
    Hurwitz, H., Bethe, H.A.: Phys. Rev. 81, 898 (1951)ADSCrossRefGoogle Scholar
  21. 21.
    Reisdorf, W., GSI version of the code ALICE, Blann, M., Plasil, F.: Phys. Rev. Lett. 29, 303 (1972)CrossRefGoogle Scholar
  22. 22.
    Wirtz, Ch., Klein, P., Kratz, J.V., Brüchle, W., Schädel, M., Gober, M.K., Zimmermann, H.P.: Proc. 4th Int. Conf. on Nuclear and Radiochemistry, Saint Malo, France, Sept. 8–13, 1996Google Scholar
  23. 23.
    Freiesleben, H., Kratz, J.V.: Phys. Rep. 106, 1 (1984)ADSCrossRefGoogle Scholar
  24. 24.
    Sahm, C.-C., Schulte, H., Vermeulen, D., Keller, J., Clerc, H.-G.: Z. Phys. A297, 241 (1980)ADSCrossRefGoogle Scholar
  25. 25.
    Bock, R., Chu, Y.T., Dakowski, M., Gobbi, A., Grosse, E., Olmi, A., Sann, H., Schwalm, D., Lynen, U., Müller, W.F.J., Bjornholm, S., Esbensen, H., Wölfli, W., Morenzoni, E.: Nucl. Phys. A388, 334 (1982)ADSCrossRefGoogle Scholar
  26. 26.
    Töke, J., Bock, R., Dai, G.X., Gobbi, A., Gralla, S., Hildenbrand, K.D., Kuzminski, J., Müller, W.F.J., Olmi, A., Stelzer, H., Back, B.B., Bjornholm, S.: Nucl. Phys. A440, 327 (1985)ADSCrossRefGoogle Scholar
  27. 27.
    Quint, A.B., Reisdorf, W., Schmidt, K.-H., Armbruster, P., Hessberger, F.P., Hofmann, S., Keller, J., Münzenberg, G., Stelzer, H., Clerc, H.-G., Morawek, W., Sahm, C.-C.: Z. Phys. A346, 119 (1993)ADSGoogle Scholar
  28. 28.
    Hessberger, F.P., Munzenberg, G., Hoffmann, S., Reisdorf, W., Schmidt, K.-H., Schött, H.J., Armbruster, P., Hingmann, R., Thuma, B., Vermeulen, D.: Z. Phys. A321, 317 (1985)ADSCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 1997

Authors and Affiliations

  • P. Klein
    • 1
  • J. V. Kratz
    • 1
  • M. K. Gober
    • 1
  • H. P. Zimmermann
    • 1
  • W. Brüchle
    • 2
  • W. Reisdorf
    • 2
  • M. Schädel
    • 2
  1. 1.Institut für KernchemieUniversit;at MainzMainzGermany
  2. 2.Gesellschaft für SchwerionenforschungDarmstadtGermany

Personalised recommendations