The reactions 12 Cϩ 116 Sn, 22 NeϩAg, 40 Arϩ 100 Mo, and 64 Znϩ 89 Y have been studied at 47A MeV projectile energy. For these reactions the most violent collisions lead to increasing amounts of fragment and light particle emission as the projectile mass increases. This is consistent with quantum molecular dynamics ͑QMD͒ model simulations of the collisions. Moving source fits to the light charged particle data have been used to gain a global view of the evolution of the particle emission. Comparisons of the multiplicities and spectra of light charged particles emitted in the reactions with the four different projectiles indicate a common emission mechanism for early emitted ejectiles even though the deposited excitation energies differ greatly. The spectra for such ejectiles can be characterized as emission in the nucleon-nucleon frame. Evidence that the 3 He yield is dominated by this type of emission and the role of the collision dynamics in determining the 3 H/ 3 He yield ratio are discussed. Self-consistent coalescence model analyses are applied to the light cluster yields, in an attempt to probe emitter source sizes and to follow the evolution of the temperatures and densities from the time of first particle emission to equilibration. These analyses exploit correlations between ejectile energy and emission time, suggested by the QMD calculations. In this analysis the degree of expansion of the emitting system is found to increase with increasing projectile mass. The double isotope yield ratio temperature drops as the system expands. Average densities as low as 0.36 0 are reached at a time near 100 fm/c after contact. Calorimetric methods were used to derive the mass and excitation energy of the excited nuclei which are present after preequilibrium emission. The derived masses range from 102 to 116 u and the derived excitation energies increase from 2.6 to 6.9 MeV/nucleon with increasing projectile mass. A caloric curve is derived for these expanded Aϳ110 nuclei. This caloric curve exhibits a plateau at temperatures near 7 MeV. The plateau extends from ϳ3.5 to 6.9 MeV/nucleon excitation energy.PACS number͑s͒: 25.70.Mn, 24.10.Lx

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He ion irradiation induced damage in several immiscible metallic nanolayer systems with incoherent interfaces has been investigated recently and a prominent size effect on mitigation of radiation damage has been observed. In general the magnitude of radiation hardening and defect cluster density are both less at smaller individual layer thickness (h) than those with larger h, as © 2014. This manuscript version is made available under the Elsevier user license http://www.elsevier.com/open-access/userlicense/1.0/ 2 interfaces can effectively reduce density of radiation induced defect clusters. Here we show, however, an opposite size dependent strengthening behavior in He ion irradiated immiscible coherent Cu/Co multilayers, that is films with smaller h have greater radiation hardening. Such unusual size dependent strengthening could be explained via a transition from partial dislocation transmission (before radiation) to full dislocation transmission (after radiation) dictated strengthening mechanisms due to formation of He bubbles at layer interface. Furthermore we show that, similar to incoherent immiscible systems, coherent interface in immiscible system can also effectively reduce the population of radiation induced defect clusters.