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Anomalous behavior of evaporative H/He from194Hg compound nuclei

  • Nuclei
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Zeitschrift für Physik A Atoms and Nuclei

Abstract

From measured cross sections for evaporative1H and4He, we have unfolded the separate effects of excitation energy (E) and spin (J) on the decay of194Hg. The analysis depends only on Bohr's independence hypothesis and on certain general features of the transmission coefficients for fusion. Evaporation-like emission of1H and4He increases rapidly with energy but decreases rather mildly with initial spin. Significant emission occurs even for very high spins where the calculated fission barrier is essentially zero. The equilibrium model for fission-evaporation competition is brought into question forE*≳98 MeV and J≳65 ħ.

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References

  1. Bohr, N., Wheeler, J.A.: Phys. Rev.56, 426 (1939)

    Google Scholar 

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

    Google Scholar 

  3. See for example, Vigdor, S.E., Karwoski, H.J., Jacobs, W.W., Kailas, S., Singh, P.P., Saga, F., Yip, P.: Phys. Lett. B90, 384 (1980)

    Google Scholar 

  4. Karwoski, H.J.: Ph.D. Thesis, University of Indiana Report No. 80-1 (1980) (unpublished)

  5. Bock, R.: Heavy ion collisions. Amsterdam, New York, London: North Holland Publ. Co. 1980

    Google Scholar 

  6. Swiatecki, W.J.: LBL Reports 10911 (1980) and 12642 and 12708 (1981); Prog. Part. Nucl. Phys.4, 383 (1980)

  7. Gregoire, C., Ngo, C., Remaud, B.: Phys. Lett.99 B, 17 (1981)

    Google Scholar 

  8. Randrup, J.: Nucl. Phys. A327, 990 (1979); LBL Report 12676 (1981) and others

    Google Scholar 

  9. Broglia, R.A., Pollarolo, G., Dasso, C.H., Døssing, T.: Phys. Rev. Lett.43, 1649 (1979) and other papers

    Google Scholar 

  10. Davies, K.T.R., Devi, D.R.S., Koonin, S.E., Strayer, M.R.: Report MAP 23, January 1982

  11. See for example, Agassi, D., Ko, C.M., Weidenmüller, H.A.: Ann. Phys. (NY)107, 140 (1977)

    Google Scholar 

  12. Ko, C.M., Agassi, D., Weidenmüller, H.A.: ibid.117, 237 (1979)

    Google Scholar 

  13. Rajagopalan, M., Logan, D., Ball, J.W., Kaplan, M., Delagrange, H., Rivet, M.F., Alexander, J.M., Vaz, L.C., Zisman, M.S.: Phys. Rev. C25, 2417 (1982)

    Google Scholar 

  14. D'Auria, J.M., Fluss, M.J., Herzog, G., Kowalski, L., Miller, J.M., Reedy, R.C.: Phys. Rev.174, 1409 (1968)

    Google Scholar 

  15. Reedy, R.C., Fluss, M.J., Herzog, G.F., Kowalski, L., Miller, J.M.: Phys. Rev.188, 1771 (1969)

    Google Scholar 

  16. Kowalski, L., Zebelman, A.M., Miller, J.M., Herzog, G.F., Reedy, R.C.: Phys. Rev. C1, 259 (1970)

    Google Scholar 

  17. Zebelman, A.M., Kowalski, L., Miller, J., Beg, K., Eyal, Y., Jaffe, G., Kandil, A., Logan, D.: Phys. Rev. C10, 200 (1974)

    Google Scholar 

  18. Galin, J., Gatty, B., Guerreau, D., Rousset, C., Schlotthauer-Voos, U.C., Tarrago, X.: Phys. Rev. C9, 1113, 1126 (1974)

    Google Scholar 

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

    Google Scholar 

  20. Logan, D., Delagrange, H., Rivet, M.F., Rajagopalan, M., Alexander, J.M., Kaplan, M., Zisman, M.S., Duek, E.: Phys. Rev. C22, 1080 (1980)

    Google Scholar 

  21. Rivet, M.F., Logan, D., Alexander, J.M., Duek, E., Zisman, M.S., Kaplan, M.: Phys. Rev. C25, 2430 (1982)

    Google Scholar 

  22. Kildir, M., Logan, D., Kaplan, M., Zisman, M.S., Guerreau, D., Alexander, J.M., Vaz, L.C.: Z. Phys. A (in press)

  23. Vaz, L.C., Logan, D., Alexander, J.M., Duek, E., Guerreau, D., Kowalski, L., Rivet, M.F., Zisman, M.S.: Preprint 1982

  24. Blann, M.: Phys. Rev. C21, 1770 (1980)

    Google Scholar 

  25. Norenberg, W., Riedel, C.: Z. Phys. A — Atoms and Nuclei290, 335 (1979)

    Google Scholar 

  26. McMahan, M.A., Alexander, J.M.: Phys. Rev. C21, 1261 (1980)

    Google Scholar 

  27. Bimbot, R., Gardes, D., Rivet, M.F.: Nucl. Phys. A189, 193 (1972)

    Google Scholar 

  28. Inamura, T., Ishihara, M., Fukuda, T., Shimoda, T., Hiruta, H.: Phys. Lett.68 B, 51 (1977)

    Google Scholar 

  29. Nomura, T., Utsunomiya, H., Motobayashi, T., Inamura, T., Yanokura, M.: Phys. Rev. Lett.40, 694 (1978)

    Google Scholar 

  30. Zolnowski, D.R., Yamada, H., Cala, S.E., Kahler, A.C., Sugihara, T.T.: Phys. Rev. Lett.41, 92 (1978)

    Google Scholar 

  31. Sarantites, D.G., Westerberg, L., Halbert, M.L., Dayras, R.A., Hensley, D.C., Barker, J.H.: Phys. Rev. C18, 774 (1978)

    Google Scholar 

  32. Siwek-Wilczynska, K., du Marchie van Voorthuysen, E.H., Popta, J. van, Siemssen, R.H., Wilczynska, J.: Phys. Rev. Lett.42, 1599 (1979)

    Google Scholar 

  33. Delagrange, H., Logan, D., Rivet, M.F., Rajagopalan, M., Alexander, J.M., Zisman, M.S., Kaplan, M., Ball, J.W.: Phys. Rev. Lett.43, 1490 (1979)

    Google Scholar 

  34. Geoffroy, K.A., Sarantites, D.G., Halbert, M.L., Hensley, D.C., Dayras, R.A., Barker, J.H.: Phys. Rev. Lett.43, 1303 (1979)

    Google Scholar 

  35. Gonthier, P., Ho, H., Namboodiri, M.N., Adler, L., Natowitz, J.B., Simon, S., Hagel, K., Terry, R., Khodai, A.: Phys. Rev. Lett.44, 1387 (1980)

    Google Scholar 

  36. Barker, J.H., Beene, J.R., Halbert, M.L., Hensley, D.C., Jaaskelainen, M., Sarantites, D.G., Woodward, R.: Phys. Rev. Lett.45, 427 (1980)

    Google Scholar 

  37. Duek, E., Kowalski, L., Rajagopalan, M., Alexander, J.M., Logan, D., Zisman, M.S., Kaplan, M.: Z. Phys. A (in press)

  38. See for example, Britt, H.C., Erkkila, B.H., Stokes, R.H., Gutbrod, H.H., Plasil, F., Ferguson, R.L., Blann, M.: Phys. Rev. C13, 1483 (1976)

    Google Scholar 

  39. Britt, H.C., Erkkila, B.H., Goldstone, P.D., Stokes, R.H., Back, B.B., Folkmann, F., Christensen, O., Fernandez, B., Garrett, J.D., Hagemann, G.B., Herskind, B., Hillis, D.L., Plasil, F., Ferguson, R.L., Blann, M., Gutbrod, H.H.: Phys. Rev. Lett.39, 1458 (1977)

    Google Scholar 

  40. Oeschler, H., Freiesleben, H., Hildenbrand, K.D., Engelstein, P., Coffin, J.P., Heusch, B., Wagner, P.: Phys. Rev. C22, 546 (1980)

    Google Scholar 

  41. Gilat, J.: Brookhaven National Laboratory Report No. BNL 50246, (1970), (unpublished)

  42. Delagrange, H.: Centre d'Etudes Nucleaires de Bordeaux-Gradignan, Report No. CENBG 7707, (1977) (unpublished)

  43. See for example, Grover, J.R., Gilat, J.: Phys. Rev.157, 802 (1967)

    Google Scholar 

  44. Grover, J.R., Gilat, J.: Phys. Rev.157, 823 (1976)

    Google Scholar 

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

    Google Scholar 

  46. Assume that the map (Fig. 5(a) for example) is essentially unchanged for all members of the evaporative decay chain. One may crudely estimate CDF orW(J) for1H as follows: (a) locate the point on the map corresponding to initial values ofE*,l crit (e.g. from Ref. 11 CDF=0.25 for1H from194Hg* withE*=82 MeV andl erit=36) (b) Note in Fig. 4(a) that the first step emission probability for1H is ≈2% forE*=82 MeV,J=36. (c) Second step probability can be estimated, forE*≈70,J≈34, to be ≈1%. (d) The remaining steps can be similarly estimated to sum to <2%. The calculated CDF is the sum of all steps and can thus be estimated to be ≈5% compared to the measured value of 0.25 for CDF

  47. Beckerman, M., Blann, M.: Phys. Rev. Lett.38, 272 (1977); Phys. Lett.68 B, 31 (1977); Phys. Rev. C17, 1615 (1978)

    Google Scholar 

  48. See for example, Carjân, N., Delagrange, H., Fleury, A.: Phys. Rev. C19, 2267 (1979)

    Google Scholar 

  49. Tōke, J., Swiatecki, W.J.: Nucl. Phys. A372, 141 (1981)

    Google Scholar 

  50. Anderson, J.U., Jensen, A.S., Jorgensen, K., Laegsgaard, E., Nielsen, K.O., Forster, J.S., Mitchell, I.V., Ward, D., Gibson, W.M., Cuomo, J.J.: Mat. Fys. Medd. Dan. Vid. Selsk.40: 7 (1980) and IAEA-SM/241-C7 (1979 IAEA, Julich)

    Google Scholar 

  51. Ericson, T.: Adv. Phys.9, 423 (1960)

    Google Scholar 

  52. Agarwal, S., Galin, J., Gatty, B., Guerreau, D., Lefort, M., Tarrago, X., Babinet, R., Girard, J.: Z. Phys. A — Atoms and Nuclei296, 287 (1980)

    Google Scholar 

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Author notes

  1. H. Delagrange

    Present address: Le Haut Vigneau, C.E.N.-Bordeaux Gradignan, F-33170, Gradignan, France

  2. M. F. Rivet

    Present address: Institut de Physique Nucléaire, B.P. N° 1, F-91406, Orsay, France

Authors and Affiliations

  1. Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York, USA

    J. M. Alexander, H. Delagrange, M. Rajagopalan, M. F. Rivet & L. C. Vaz

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  1. J. M. Alexander
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Alexander, J.M., Delagrange, H., Rajagopalan, M. et al. Anomalous behavior of evaporative H/He from194Hg compound nuclei. Z Physik A 307, 149–158 (1982). https://doi.org/10.1007/BF01414829

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