FIZIKA B 16 (2007) 1, 49 - 58
LETTER TO THE EDITOR
SOME INDICATIONS OF LIQUID-GAS PHASE TRANSITION IN ELECTRON-INDUCED
FRAGMENTATION OF 197Au NUCLEI
G. E. MARKARYAN
Yerevan Physics Institute, 375036 Yerevan, Armenia
E-mail address: garik@mail.yerphi.am
Received 21 October 2006; Revised manuscript received 25 April 2007
Accepted 16 May 2007 Online 21 June 2007
The energy spectra and fragment yields (5<ZF<10) obtained in
1.5 - 4.5 GeV e + 197Au inclusive reactions are analysed. Based
on the observed correlation between a decrease in the fragment yields and an
increase in the fragment Coulomb energy with the fragment charge,
temperatures of the fragmenting system are derived. It is shown that
the fragment yields exhibit the feature of thermal scaling in accordance
with the Fisher's droplet model. By using this model, values for the zero
temperature surface energy coefficient, c0=11.8±0.8 MeV, the critical exponent, s
= 0.56±0.03, as well as estimation of the
critical temperature, Tc » 18 MeV are obtained. The obtained results
argue in favour of nuclear liquid-gas phase transition in these
electron-induced reactions.
PACS numbers: 25.30.-c, 25.30.Rw
UDC 539.172
Keywords: electron-induced fragmentation, fragment cross sections,
Coulomb energies, thermal scaling, Fisher's droplet model, liquid-gas phase transition
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