# Isotopic Scaling and the Symmetry Energy in Spectator Fragmentation

Abstract : Isotopic effects in the fragmentation of excited target residues following collisions of $^{12}$C on $^{112,124}$Sn at incident energies of 300 and 600 MeV per nucleon were studied with the INDRA 4$\pi$ detector. The measured yield ratios for light particles and fragments with atomic number $Z \leq$ 5 obey the exponential law of isotopic scaling. The deduced scaling parameters decrease with increasing centrality to values as low as $\alpha = 0.25 \pm 0.02$ for the central event group at 600 MeV per nucleon. Symmetry term coefficients, deduced from these data within the statistical description of isotopic scaling, are near $\gamma =$ 25 MeV for peripheral and $\gamma <$ 10 MeV for central collisions.
Document type :
Journal articles

http://hal.in2p3.fr/in2p3-00023603
Contributor : Suzanne Robert <>
Submitted on : Thursday, February 17, 2005 - 10:52:34 AM
Last modification on : Tuesday, September 3, 2019 - 1:58:02 PM

### Citation

A. Le Fèvre, G. Auger, M. L. Begemann-Blaich, N. Bellaize, R. Bittiger, et al.. Isotopic Scaling and the Symmetry Energy in Spectator Fragmentation. Physical Review Letters, American Physical Society, 2005, 94, pp.162701(1-5). ⟨10.1103/PhysRevLett.94.162701⟩. ⟨in2p3-00023603⟩

Record views