Mass dependence of critical behavior in nucleus-nucleus collisions

Hot nuclear matter in asymmetry chiral sigma model

“…The corresponding P c and n c are 0.14, 0.22 and 0.36 MeV fm −3 and 0.035, 0.044 and 0.051 fm −3 , respectively. These are in the range of recent experimental observation, 13.1 ± 0.6 [21]. Precisely, set I is close to this value.…”

“…This value was brought down to 14.2 MeV, if the non-linear terms were included in the model. However, recent experiments in heavy-ion collisions for dilute warm nuclear matter report a small liquid gas phase region and low critical temperature∼ 13.1 ± 0.6 MeV [21]. It has been noticed that the different critical temperature are extracted by various theories.…”

“…The critical temperature obtained by the density dependent relativistic mean-field theory [27] (T c =12.66 MeV) and the experimental value (T c = 13.1 ± 0.6 MeV) [21] are comparable to the T c obtained in our calculation with set I. As we emphasized in section I, if one consider the original Walecka model [13] (no non-linear terms), the critical temperature is T c ≈ 18.3.…”

“…The main interest to study finite temperature nuclear EOS is to observe the liquid gas phase transition [21] near normal nuclear matter density. It is also required to estimate the critical temperature at liquid gas coexistence point.…”

Density fluctuations and multifragmentation of nuclear matter

“…Since experimentally the fragments are detected according to their charge, we have to transform P (A, t) and Y (A) into the corresponding functions of Z. We assume a homogeneous distribution also for the charge The power-law behaviour of the fragment yield and the determination of the exponent have been the subject of several experimental studies of multifragmentation ( see for example the recent papers [34,35] ). The observed values of the exponent are in the interval ∼ 1.2−1.5 for nuclear rections with beam energies lower than ∼ 40 A MeV, whereas they exceed the value of 2 at higher energies [34,35].…”