Isospin Observables from Fragment Energy Spectra

ORAL

Abstract

The energy spectra of light charged particles and intermediate mass fragments from $^{112}$Sn+$^{112}$Sn and $^{124}$Sn+$^{124}$Sn collisions at an incident energy of E/A=50 MeV have been measured with a large array of Silicon strip detectors. We used charged particle multiplicities detected in a near 4pi array to select data from the central collision region. We study isospin observables analogous to ratios of neutron and proton spectra, including double ratios and yield ratios of t/$^{3}$He and of asymmetries constructed from fragments with Z=3-8. Using the energy spectra, we can construct these observables as functions of kinetic energy and observe a large difference in the fragment observables if fragments contributing to sequential decays are included.

*This work has been supported by the U.S. National Science Foundation under Grants PHY 060007 and the Department of Energy under grant numbers DE-FG02-87ER-40316 (WU) and DE-FG02-88ER-40404 (IU).

Authors

  • Rachel Hodges

    • NSCL/MSU
  • T.X. Liu

    • NSCL/MSU
  • W.G. Lynch

    • National Superconducting Cyclotron Laboratory, Michigan State University, Physics and Astronomy Department
    • National Superconducting Cyclotron Laboratory and Michigan State University
    • NSCL/MSU
    • MSU / NSCL
    • NSCL / MSU
  • M.B. Tsang

    • National Superconducting Cyclotron Laboratory, Michigan State University, Physics and Astronomy Department
    • National Superconducting Cyclotron Laboratory and Michigan State University
    • NSCL/MSU
    • MSU / NSCL
    • NSCL / MSU
  • X.D. Liu

    • NSCL/MSU
  • W.P. Tan

    • NSCL/MSU
  • M.J. van Goethem

    • NSCL/MSU
  • G. Verde

    • NSCL/MSU
  • A. Wagner

    • NSCL/MSU
  • H.F. Xi

    • NSCL/MSU
  • H.S. Xu

    • NSCL/MSU
  • M. Famiano

    • WMU
  • R.T. de Souza

    • IU
  • V.E. Viola

    • IU
  • R.J. Charity

    • WU
  • L.G. Sobotka

    • WU