Multifragmentation and the Phase Transition: A Systematic Study of the MF of 1A GeV Au, La, and Kr

Abstract

A systematic analysis of the multifragmentation (MF) in fully reconstructed events from 1A GeV Au, La and Kr collisions with C has been performed. This data is used to provide a definitive test of the variable volume version of the statistical multifragmentation model (SMM). A single set of SMM parameters directly determined by the data and the semi-empiricalmass formula are used after the adjustable inverse level density parameter, ${\epsilon }_o$ is determined by the fragment distributions. The results from SMM for second stage multiplicity, size of the biggest fragment and the intermediate mass fragments are in excellent agreement with the data. Multifragmentation thresholds have been obtained for all three systems using SMM prior to secondary decay. The data indicate that both thermal excitation energy $E_{th}^{\ast }$ and the isotope ratio temperature $T_{He-DT}$ decrease with increase in system size at the critical point. The breakup temperature obtained from SMM also shows the same trend as seen in the data. The SMM model is used to study the nature of the MF phase transition. The caloric curve for Kr exhibits back-bending (finite latent heat) while the caloric curves for Au and La are consistent with a continuous phase transition (nearly zero latent heat) and the values of the critical exponents $\tau$, $\beta$ and $\gamma$, both from data and SMM, are close to those for a 'liquid-gas' system for Au and La. We conclude that the larger Coulomb expansion energy in Au and La reduces the latent heat required for MF and changes the nature of the phase transition. Thus the Coulomb energy plays a major role in nuclear MF.

43 pages, 25 figures

References in corpus (3)

• Caloric curves and critical behavior in nuclei
• Event-by-Event Analysis of Proton-Induced Nuclear Multifragmentation: Determination of Phase Transition Universality-Class in System with Extreme Finite-Size Constraints
• Baryon Number Fluctuation and the Quark-Gluon Plasma

Cited by in corpus (18)

• Nuclear multifragmentation and phase transition for hot nuclei
• Role of isospin in the nuclear liquid-gas phase transition
• Isospin and symmetry energy effects on nuclear fragment production in liquid-gas type phase transition region
• Critical Temperature for the Nuclear Liquid-Gas Phase Transition
• Cnstructing the phase diagram of finite neutral nuclear matter
• The critical temperature of nuclear matter and fragment distributions in multifragmentation of finite nuclei
• Statistical description of nuclear break-up
• Liquid-Gas Phase Transition of Supernova Matter and Its Relation to Nucleosynthesis
• Temperature determined by isobaric yield ratio in heavy-ion collisions
• Fluctuations of fragment observables
• Nuclear multifragmentation time-scale and fluctuations of largest fragment size
• Speed of sound and liquid-gas phase transition in nuclear matter
• Improved Thermometer from Intermediate Mass Fragments in Heavy-Ion Collisions with Isobaric Yield Ratio Difference
• Possible links between the liquid-gas and deconfinement-hadronization phase transitions
• Probing nuclear liquid-gas phase transition with isospin correlations
• Baryon number fluctuations induced by hadronic interactions at low temperature and large chemical potential
• Mass distributions for nuclear disintegration from fission to evaporation
• Critical Opalescence: An Optical Signature for a QCD Critical Point