Eur. Phys. J. A 10, 381-385

Isospin dependence of the isotopic distributions from ³⁶Ar and ⁴⁰Ar fragmentation at about 60 MeV/nucleon

D.Q. Fang¹, W.Q. Shen^{1, 2}, J. Feng¹, X.Z. Cai¹, Y.G. Ma¹, H.Y. Zhang¹, P.Y. Hu¹, W.L. Zhan³, Z.Y. Guo³, G.Q. Xiao³, J.X. Li³, M. Wang³, J.F. Wang³, Z.J. Ning³, J.Q. Wang³, J.S. Wang³, Q.J. Wang³ and Z.Q. Chen<sup>3

1</sup>  Shanghai Institute of Nuclear Research, Chinese Academy of Sciences, Shanghai 201800, China
²  Ningbo University, Ningbo 315211, China
³  Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China

dqfang@mailcity.com

(Received: 15 November 2000 / Revised version: 4 April 2001 Communicated by W.F. Henning)

Abstract
Fragments produced in the reactions of 69 MeV/nucleon ³⁶Ar and 55 MeV/nucleon ⁴⁰Ar on a Be target have been measured experimentally. The isotopic distributions from fragmentation reaction for both projectiles are compared with modified statistical abrasion-ablation model calculations. A strong isospin effect exhibits in the fragment distributions produced in ³⁶Ar and ⁴⁰Ar fragmentation. Experimental evidence for the disappearance of the isospin effect in the isotopic distributions produced by projectile fragmentation is observed with the increase of the violence of nuclear reaction.

PACS
25.70.Mn - Projectile and target fragmentation.
24.10.-i - Nuclear-reaction models and methods.

© Società Italiana di Fisica, Springer-Verlag 2001