Fusionlike reactions ofAr40up to 1.36 GeV: Prethermalization and postthermalization particles and fragments

Multifragmentation process for different mass asymmetry in the entrance channel around the Fermi energy

“…Numerous event selection methods have been already used in order to select multifragmentation events [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. These methods are mostly based on cuts in global variables distributions.…”

Balance of Mass, Momentum, and Energy in Splintering Central Collisions forA40rup to 115 MeV/Nucleon

“…As described in [1] we use these data to characterize the heaviest fragment in terms of its mass and longitudinal velocity; experimental details are given there. For data acquisition a minimum of two hits were required for 18 ± , u , 162 ± (thresholds 17 and 12 MeV for 1 H and 4 He)For mass asymmetric reactions in the near-barrier energy domain of &20A MeV it has long been conventional to resolve light ejectile emission into an isotropic and a forward-peaked component, e.g., [3,4], commonly termed the evaporation and direct components. For incident energies greater than ϳ30A MeV, experiments have often been performed with near 4p detector arrays that give a wonderful view of the light or fast ejectiles [2].…”

“…For mass asymmetric reactions in the near-barrier energy domain of &20A MeV it has long been conventional to resolve light ejectile emission into an isotropic and a forward-peaked component, e.g., [3,4], commonly termed the evaporation and direct components. For incident energies greater than ϳ30A MeV, experiments have often been performed with near 4p detector arrays that give a wonderful view of the light or fast ejectiles [2].…”

“…As in [1] we select violent central collisions via the highest 15% of the multiplicity distributions and require that each event include $75% of the system charge and $70% of the incident momentum. We group the various ejectiles into two components: (a) an isotropic component in the frame of the heaviest fragment, and (b) a forward-directed component in this frame [3,4]. We determine the average linear momentum for various ejectile types of each component and hence characterize the residual system after the forward ejections and prior to the isotropic emission.…”

“…[4] heavy fragment velocities were measured and used, along with a 4p array for light particles, to resolve H, He, and Li fragments into isotropic and forward-directed components. Here we have followed the same procedure.…”