Kinetic freeze-out temperature and flow velocity extracted from transverse momentum spectra of final-state light flavor particles produced in collisions at RHIC and LHC

Abstract

Abstract:The transverse momentum spectra of final-state light flavor particles produced in proton-proton (p-p), copper-copper (Cu-Cu), gold-gold (Au-Au), lead-lead (PbPb), and proton-lead (p-Pb) collisions for different centralities at relativistic heavy ion collider (RHIC) and large hadron collider (LHC) energies are studied in the framework of a multisource thermal model. The experimental data measured by the STAR, CMS, and ALICE Collaborations are consistent with the results calculated by the multi-component Erlang distribution and Tsallis Statistics. The effective temperature and real temperature (kinetic freeze-out temperature) of interacting system at the stage of kinetic freeze-out, the mean transverse flow velocity and mean flow velocity of particles, and the relationships between them are extracted. The dependences of effective temperature and mean (transverse) momentum on rest mass, moving mass, centrality, and center-of-mass energy, and the dependences of kinetic freeze-out temperature and mean (transverse) flow velocity on centrality, center-of-mass energy, and system size are obtained.

Examining the model dependence of the determination of kinetic freeze-out temperature and transverse flow velocity in small collision system

“…This substitution results in a small and negligible difference in the Tsallis distribution [19]. iii) An alternative method, in which the intercept in the T versus m 0 relation is assumed to be T 0 [7,[10][11][12][13], the slope in the p T versus m relation is assumed to be β T , and the slope in the p versus m relation is assumed to be the radial flow velocity β [14][15][16][17], which does not include the contribution of longitudinal flow. Here m 0 denotes the rest mass, m denotes the mean moving mass (mean energy), ... denotes the theoretical distribution average of the considered quantity, and T is obtained from a Boltzmann distribution [18].…”

“…[6][7][8][9][10][11][12][13], different methods have been used to obtain T 0 and β T . In our recent studies [14][15][16][17], we have used a number of models to obtain T 0 and β T in nucleus-nucleus [gold-gold (Au-Au) and leadlead (Pb-Pb)] collisions at the RHIC and Large Hadron Collider (LHC) energies, where the top RHIC energy was √ s N N = 200 GeV while the LHC energy reached a few TeV. Similar results were obtained when a nonzero β T was used in peripheral nucleus-nucleus collisions in the Blast-Wave model with Boltzmann-Gibbs statistics (BGBW model) [6][7][8]18] and with Tsallis statistics (TBW model) [9,18,19].…”

Initial and Final State Temperatures of Antiproton Emission Sources in High Energy Collisions

“…Both initial and final state temperatures are expected to obtain from particle spectra measured in experiments. In particular, the final state temperature is in fact the kinetic freeze-out temperature (T 0 ) which is writhen to transverse flow velocity (β T ) [2][3][4]. Both T 0 and β T can be extracted from transverse momentum (p T ) spectra of particles.…”

“…It is well known that nowadays the Tsallis distribution [48][49][50] is quite of use and seems to be very successful. In our previous work [4,34,42,44,45,51,52], we have used the Tsallis distribution and related functions to analyze the particle production in high energy collisions. To express the variousness of fit functions, we have used other functions in this work.…”

Comparing Standard Distribution and Its Tsallis Form of Transverse Momenta in High Energy Collisions

“…Empirically, the chemical potential for baryon is [23][24][25][26] 1.303 1 0.286 We would like to point out that Eqs. (16) and (23) As for the methods to obtain the real temperature by disengaging the contributions of thermal motion and flow effect, we can use the blast-wave model based on the Boltzmann distribution [28][29][30], the blast-wave model based on the Tsallis distribution [31], the improved Tsallis distribution [32,33], some alternative methods [21,29,[34][35][36], and others [37][38][39][40]. These methods themselves are beyond the focus of the present work.…”