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Methods of extraction of the symmetry energy (or enthalpy) coefficient to temperature ratio from isobaric and isotopic yields of fragments produced in Fermi-energy heavy-ion collisions are discussed. We show that the methods are consistent when the hot fragmenting source is well characterized and its excitation energy and isotopic composition are properly taken into account. The results are independent of the mass number of the detected fragments, which suggests that their fate is decided very early in the reaction.

Quasi-elastic scattering of 6 He at E lab =27 MeV from 197 Au has been measured in the angular range of 6• − 72• in the laboratory system employing LEDA and LAMP detection systems. These data, along previously analysed data of 6 He + 208 Pb at the same energy, are analysed using Optical Model calculations. The role of Coulomb dipole polarizability has been investigated. Large imaginary diffuseness parameters are required to fit the data. This result is an evidence for long range absorption mechanisms in 6 He induced reactions.

The transverse flow and relative mid-rapidity yield of isotopically identified light charged particles (LCPs) Ni systems. A large enhancement of the mid-rapidity yield of the LCPs was observed relative to the yield near the projectile rapidity. In particular, this enhancement was increased for the more neutron-rich LCPs demonstrating a preference for the production of neutron-rich fragments in the mid-rapidity region. Additionally, the transverse flow of the LCPs was extracted which provides insight into the average movement of the particles in the mid-rapidity region. Isotopic and isobaric effects were observed in the transverse flow of the fragments. In both cases, the transverse flow was shown to decrease with an increasing neutron content in the fragments. A clear inverse relationship between the transverse flow and relative mid-rapidity yield is shown. The increased relative mid-rapidity emission produces a decreased transverse flow. The Stochastic Mean-Field model was used for comparison to the experimental data. The results showed that the model was able to reproduce the general isotopic and isobaric trends for the mid-rapidity emission and transverse flow. The sensitivity of these observables to the density dependence of the symmetry energy was explored. The results indicate that the transverse flow and mid-rapidity emission of the LCPs are sensitive to the denisty dependence of the symmetry energy.

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