Signals for a Transition from Surface to Bulk Emission in Thermal Multifragmentation

Abstract

Excitation-energy-gated two-fragment correlation functions have been studied between 2 to 9A MeV of excitation energy for equilibrium-like sources formed in ${\pi }^{-}$ and p + ${}^{197}$Au reactions at beam momenta of 8,9.2 and 10.2 GeV/c. Comparison of the data to an N-body Coulomb-trajectory code shows a decrease of one order of magnitude in the fragment emission time in the excitation energy interval 2-5A MeV, followed by a nearly constant breakup time at higher excitation energy. The observed decrease in emission time is shown to be strongly correlated with the increase of the fragment emission probability, and the onset of thermally-induced radial expansion. This result is interpreted as evidence consistent with a transition from surface-dominated to bulk emission expected for spinodal decomposition.

11 pages including 3 postscript figures (1 color)

References in corpus (2)

• Thermal excitation of heavy nuclei with 5-15 GeV/c antiproton, proton and pion beams
• Is binary sequential decay compatible with the fragmentation of nuclei at high energy?

Cited by in corpus (54)

• Nuclear multifragmentation and phase transition for hot nuclei
• Isoscaling in Light-Ion Induced Reactions and its Statistical Interpretation
• The liquid to vapor phase transition in excited nuclei
• Isotopic Scaling and the Symmetry Energy in Spectator Fragmentation
• Critical Behavior in Light Nuclear Systems: Experimental Aspects
• Isospin dependent multifragmentation of relativistic projectiles
• Evidence for Spinodal Decomposition in Nuclear Multifragmentation
• Monte-Carlo generator of heavy ion collisions DCM-SMM
• Microscopic model approaches to fragmentation of nuclei and phase transitions in nuclear matter
• Symmetry energy and the isospin dependent equation of state
• Fragment Isotope Distributions and the Isospin Dependent Equation of State
• Critical Temperature for the Nuclear Liquid-Gas Phase Transition
• Symmetry energy and the isoscaling properties of the fragments produced in ${}^{40}$Ar, ${}^{40}$Ca + ${}^{58}$Fe, ${}^{58}$Ni reactions at 25 $-$ 53 MeV/nucleon
• Cnstructing the phase diagram of finite neutral nuclear matter
• Mechanical and chemical spinodal instabilities in finite quantum systems
• The statistical multifragmentation model for liquid-gas phase transition with a compressible nuclear liquid
• Correlations and Characterization of Emitting Sources
• Isospin Effects in Nuclear Multifragmentation
• Thermal and Chemical Freeze-out in Spectator Fragmentation
• Light-Ion-Induced Multifragmentation: The ISiS Project
• Evidence of Critical Behavior in the Disassembly of Nuclei with A ~ 36
• Statistical description of nuclear break-up
• Thermal Bremsstrahlung photons probing the nuclear caloric curve
• Critical parameters of consistent relativistic mean-field models
• Intermediate-mass fragments from fission and multifragmentation in the spallation of 136Xe
• Comparison of mid-velocity fragment formation with projectile-like decay
• N/Z Dependence of Projectile Fragmentation
• Compound nuclear decay and the liquid to vapor phase transition: a physical picture
• Short timescale behavior of colliding heavy nuclei at intermediate energies
• Investigation of collective radial expansion and stopping in heavy ion collisions at Fermi energies
• Symmetry energy of fragments produced in multifragmentation
• Formation of hypernuclei in evaporation and fission processes
• Thermally-induced expansion in the 8 GeV/c ${\pi }^{-}$ + ${}^{197}$Au reaction
• Nuclear multifragmentation and fission: similarity and differences
• The Nuclear Liquid-Gas Phase Transition: Q.E.D
• The decay time scale for highly excited nuclei as seen from asymmetrical emission of particles
• Kinetic energy spectra for fragments and break-up density in multifragmentation
• Tracking the phase-transition energy in disassembly of hot nuclei
• Tidal effects and the Proximity decay of nuclei
• The role of bulk energy in nuclear multifragmentation
• Caloric curve of 8 GeV/c negative pion and antiproton + Au reactions
• Moment Analysis and Zipf Law
• d-alpha Correlation functions and collective motion in Xe+Au collisions at E/A=50 MeV
• Coulomb chronometry to probe the decay mechanism of hot nuclei
• On growth of spinodal instabilities in nuclear matter
• Comment on "Negative heat capacities and first order phase transitions in nuclei" by L.G. Moretto et al
• Source shape determination with directional fragment-fragment velocity correlations
• Centrality dependence of the thermal excitation-energy deposition in 8-15 GeV/c hadron-Au reactions
• Coupled collective motion in nuclear reactions
• Spinodal decomposition of expanding nuclear matter and multifragmentation
• Properties of hot finite nuclei and associated correlations with infinite nuclear matter
• Fragmentation Experiment and Model for Falling Mercury Drops
• Quantum corrections for pion correlations involving resonance decays
• Analysis of critical parameters for nonrelativistic models in symmetric nuclear matter