اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدThermodynamical features of multifragmentation in peripheral Au + Au Collisions at 35 A.MeV
85
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
The distribution of fragments produced in events involving the multifragmentation of excited sources is studied for peripheral Au + Au reactions at 35 A.MeV. The Quasi-Projectile has been reconstructed from its de-excitation products. An isotropic emission in its rest frame has been observed, indicating that an equilibrated system has been formed. The excitation energy of the Quasi-Projectile has been determined via calorimetry. A new event by event effective thermometer is proposed based on the energy balance. A peak in the energy fluctuations is observed related to the heat capacity, suggesting that the system undergoes a liquid-gas type phase transition at an excitation energy about 5 A.MeV and a temperature 4 - 6 MeV, dependent on the freeze-out hypothesis. By analyzing different regions of the Campi-plot, the events associated with the liquid and gas phases as well as the critical region are thermodynamically characterized. The critical exponents, tau, beta,gamma, extracted from the high moments of the charge distribution are consistent with a liquid-gas type phase transition.
قيم البحث
اقرأ أيضاً
Multifragment disintegrations, measured for central Au + Au collisions at E/A = 35 MeV, are analyzed with the Statistical Multifragmentation Model. Charge distributions, mean fragment energies, and two-fragment correlation functions are well reproduc
ed by the statistical breakup of a large, diluted and thermalized system slightly above the multifragmentation threshold.
The signals theoretically predicted for the occurrence of a critical behavior (conditional moments of charge distributions, Campi scatter plot, fluctuations of the size of the largest fragment, power law in the charge distribution, intermittency) hav
e been found for peripheral events in the reaction Au+Au at 35 MeV/u. The same signals have been studied with a dynamical model which foresees phase transition, like the Classical Molecular Dynamics.
Multifragment events resulting from peripheral Au + Au collisions at 35 MeV/nucleon are analysed in terms of critical behavior. The analysis of most of criticality signals proposed so far (conditional moments of charge distributions, Campi scatter pl
ot, fluctuations of the size of the largest fragment, intermittency analysis) is consistent with the occurrence of a critical behavior of the system.
The fragmentation resulting from peripheral Au + Au collisions at an incident energy of E = 35 MeV/nucleon is investigated. A power-law charge distribution, $A^{-tau}$ with $tau approx 2.2$, and an intermittency signal are observed for events selecte
d in the region of the Campi scatter plot where critical behavior is expected.
We performed a systematic study of the formation of fragments with different mass ranges in 197Au+197Au collisions at incident energies between 20 - 1000 MeV/nucleon and at impact para- meter between ^b = 0-0.98. The aim of present study is to unders
tand the complex dependence of fragment production on incident energy and impact parameter. Our results clearly indicate that the QMD simulations of 197Au+197Au predict different behavior for different mass ranges than for IMFs with a change in incident energy and impact parameter. All charge yields can be parameterized by a power law and no signal of liquid-gas phase transition is seen as no unique dependence of tau on impact parameter is seen.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
