Abstract
Longitudinal momentum () distributions of projectilelike fragments produced at are investigated. distributions of fragments produced by Ar and Kr beams with a wide variety of targets (C, Al, Nb, Tb, and Au) were measured using the fragment separator at HIMAC. distributions observed for fragments with a wide range of mass losses (1–30 for Ar beam and 1–64 for Kr beam), show a slightly, but definitely asymmetric nature. The peak shift and width were obtained from the observed distributions. No significant target dependence was found in either the peak shift or width. For the practical application, the variation in momentum peak shift with fragment mass () was represented by a parabolic function. The width on the high- side () is well reproduced by the Goldhaber formula, which is obtained from the contribution of the Fermi momentum. The behavior of the reduced width, , obtained from via the Goldhaber formulation, is consistent with the mass-dependent Fermi momentum of a nucleon. The width on the low- side () is markedly larger than and exhibits a clear dependence.
11 More- Received 27 October 2017
- Revised 27 January 2018
DOI:https://doi.org/10.1103/PhysRevC.97.044604
©2018 American Physical Society