Advertisement

Strength Functions and Intermediate Structure

  • Henry W. Newson

Abstract

About five years ago at the neutron conference in Antwerp,(1) I reviewed the status of strength functions. We were plagued by some instrumental difficulties which, however, have been cleared up mostly by the efforts of Divadeenam(2) and Bilpuch and this happy development was reported about a year later at the Washington neutron conference.(3) As a result of this improvement in reliability, we decided that a further effort on average cross sections would lead to enough new and accurate data to make a considerable improvement in the optical model interpretation of cross sections and hopefully to obtain a set of parameters which would reproduce the experimental facts accurately over most of the Periodic Table. Figure 1A shows the most optimistic interpretation of the labors involved in the theses of Pineo,(4) Divadeenam, Tabony(2) and of earlier work.(5) In this slide we have not broken up the cross section curves into their s- and p-wave components but have simply plotted the cross sections averaged from 300 to 650 keV. One sees immediately that the experimental points bring out only the strong p-wave peak at A = 90 and the two strong s-wave peaks (not well resolved) in the rare earth region. The theoretical calculations by the models of Buck and Perey(6) and of Tamura(7) are also shown.

Keywords

Total Cross Section Strength Function Intermediate Structure Average Cross Section Giant Resonance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    H. W. Newson, Nuclear Structure Study with Neutrons (Antwerp, 1966).Google Scholar
  2. 2.
    M. Divadeenam, Ph.D. Thesis (1967), Duke University (unpublished). M. Divadeenam and H. W. Newson, Bull. Am. Phys. Soc. 12, 106 (1966).Google Scholar
  3. 3.
    H. W Newson, Neutron Cross Sections and Technology Conference (Washington, 1968).Google Scholar
  4. 4.
    W. F. E. Pineo, Ph.D. Thesis (1970), Duke University (unpublished). W. F. E. Pineo, M. Divadeenam, E. G. Bilpuch, and H. W. New-son, Bull. Am. Phys. Soc. 15, 568 (1970).Google Scholar
  5. 5.
    K. K. Seth, R. H. Tabony, E. G. Bilpuch, and H. W. Newson, Physics Letters 13, 70 (1964). K. K. Seth, R. H. Tabony, E. G. Bilpuch, and H. W. Newson, Comptes Rendus du Congres International de Physique Nucleaire, 1964 (Paris). R. H. Tabony, Ph. D. Thesis (1966), Duke University (unpublished).ADSCrossRefGoogle Scholar
  6. 6.
    B. Buck and F. Perey, Phys. Rev. Letters 8, 446 (1962). The total cross sections versus A curve was generated by using the strength functions and R′ given in this reference.ADSCrossRefGoogle Scholar
  7. 7.
    T. Tamura, ORNL Report No. 4152 (Coupled Channel Computer Program JUPITOR I). RevS. of Mod. Phys. 37, 679 (1965). Computor Code JUPITOR I was used at Oak Ridge by M. Divadeenam and at Duke by W. F. E. Pineo.Google Scholar
  8. 8.
    P. H. Stelson and L. Grodzins, Nuclear Data 1,427 (1965).CrossRefGoogle Scholar
  9. 9.*
    B. Block and H. Feshbach, Ann. of Phys. 23, 49 (1963).ADSCrossRefGoogle Scholar
  10. l0.
    R. C. Block, private communications.Google Scholar
  11. 11.
    J. B. Garg, U. N. Singh, J. Rainwater, W. W. Havens, Jr. and S. Wynchank, these proceedings. U. N. Singh, J. B. Garg, J. Rainwater, S. Wynchank, M. Slago-witz, and H. Liou, these proceedings.Google Scholar
  12. 12.
    P. Moldauer, Nucl. Phys. 47, 65 (1963).CrossRefGoogle Scholar
  13. 13.
    J. A. Farrell, G. C. Kyker, Jr., E. G. Bilpuch, and H. W. Newson, Phys. Letters 17, 286 (1965).ADSCrossRefGoogle Scholar
  14. 14.
    E. G. Bilpuch, these proceedings (Section 2).Google Scholar
  15. 15.
    J. G. Malan, W. F. E. Pineo, M. Divadeenam, E. G. Bilpuch, and H. W. Newson, unpublished.Google Scholar
  16. 16.
    F. Seibel, Ph.D. Thesis (1968), Duke University (unpublished).Google Scholar
  17. 17.
    F. Seibel, E. G. Bilpuch, and H. W. Newson, Ann. of Phys. (in press).Google Scholar
  18. 18.
    M. Divadeenam and W. P. Beres, these proceedings (Section 8). W. P. Beres and M. Divadeenam, Phys. Rev. Letters 25, 596 (1970). M. Divadeenam, W. P. Beres, and H. W. Newson, Ann. of Phys. (in press). M. Divadeenam, E. G. Bilpuch, and H. W. Newson, Bull. Am. Phys. Soc. 16, 495 (1971).Google Scholar
  19. 19.
    M. Divadeenam, unpublished.Google Scholar
  20. 20.
    C.D. Bowman, E. G. Bilpuch, and H. W. Newson, Ann. of Phys. 17, 319 (1962). J. A. Farrell, E. G. Bilpuch, and H. W. Newson, Ann. of Phys. 37, 367 (1966). E. G. Bilpuch, K. K. Seth, C. D. Bowman, R. H. Tabony, R. C. Smith, and H. W. Newson, Ann. of Phys. 14, 387 (1961).ADSCrossRefGoogle Scholar
  21. 21.
    A.J. Elwyn, and J. Monahan, Nucl. Phys. A123, 33 (1969).ADSGoogle Scholar
  22. 22.
    R. B. Shwartz, R. A. Schrack, and H. T. Heaton, Bull. Am. Phys. Soc. 16, 495 (1971), and private communication.Google Scholar
  23. 23.
    W. F. E. Pineo, E. G. Bilpuch, H. W. Newson and J. G. Malan, Bull. Am. Phys. Soc. 16, 495 (1971).Google Scholar
  24. 24.
    Wisconsin measurements and BNL 325.Google Scholar

Copyright information

© Plenum Press 1972

Authors and Affiliations

  • Henry W. Newson
    • 1
  1. 1.Triangle Universities Nuclear Laboratory and Duke UniversityDurhamUSA

Personalised recommendations