Title: Comparison of the isotopic distributions measured in the fragmentation of 136Xe and 124Xe projectiles with the EPAX parameterization
1 Comparison of the isotopic distributions
measured in the fragmentation of 136Xe and 124Xe
projectiles with the EPAX parameterization
Daniela Henzlova GSI-Darmstadt,
Germany NSCL-MSU, East Lansing, Michigan
2 Overview of the measured cross sections
- more than 1100 production cross sections over 4
orders of magnitude - broad nuclear charge range Z3(5)-56(55) for
136Xe(124Xe)
- extensive database for comparison with
up-to-date parameterizations - EPAX2 - based on fragmentation reactions of
medium to heavy-mass projectiles in relativistic
heavy-ion collisions
3 Isotopic resolution of FRS
124Xe
136Xe
NZk, k4
136Xe Pb 1A GeV
Z50
Z54
- final fragments in broad range unambiguously
identified
4 Overview of the isotopic distributions
5 Comparison with EPAX lower Z
EPAX for 124XePb
EPAX for 136XePb
- underestimation of production cross sections of
lighter isotopes
6 Comparison with EPAX higher Z
EPAX for 124XePb
EPAX for 136XePb
- underestimation of cross sections of isotopes on
the less n-rich side of the isotopic
distributions in case of 136Xe projectile
- slightly worse agreement with data from more
n-rich projectile
7 Comparison with EPAX2 available data
J. Friese et al., Nucl. Phys. A 553 (1993) 753c
R. Schneider, PhD thesis, TU München (1996)
Zeit. für Phys. A 348 (1994) 241
J. Reinhold et al., Phys. Rev. C 58 (1998) 247
this work
- scarce experimental data for n-rich Xe isotope
available
8 Comparison with EPAX mean N-over-Z
- higher ltNgt/Z in the vicinity of the 136Xe
projectile
- low values of ltNgt/Z of the residues far from both
projectiles
9 Comparison with EPAX mass distributions
- mass yields for both systems considerably
underestimated
10 Summary
- strong underestimation of lighter residues
production cross sections independently of system
isospin
- underestimation of less n-rich isotopes for
residues in the vicinity of 136Xe projectile
- overall 136Xe data worse reproduced
- too strong loss of memory on initial N/Z
- underestimation of mass yields for both Xe
projectiles
present data may serve to refine the EPAX
formulation