Determination of temperature and transverse flow velocity at chemical freeze-out in relativistic nuclear interactions

1996 ◽  
Vol 53 (3) ◽  
pp. 1353-1362 ◽  
Author(s):  
A. D. Panagiotou ◽  
G. Mavromanolakis ◽  
J. Tzoulis
Keyword(s):  
Flow Velocity ◽  
Transverse Flow ◽  
Nuclear Interactions ◽  
Transverse Flow Velocity ◽  
Chemical Freeze ◽  
Freeze Out

scholarly journals Analyzing Transverse Momentum Spectra of Pions, Kaons and Protons in p–p, p–A and A–A Collisions via the Blast-Wave Model with Fluctuations

Entropy ◽  
2021 ◽  
Vol 23 (7) ◽  
pp. 803
Author(s):  
Hai-Ling Lao ◽  
Fu-Hu Liu ◽  
Bo-Qiang Ma
Keyword(s):  
Transverse Momentum ◽  
Flow Velocity ◽  
Blast Wave ◽  
Proper Time ◽  
Wave Model ◽  
Transverse Flow ◽  
Momentum Spectra ◽  
Transverse Momentum Spectra ◽  
Transverse Flow Velocity ◽  
Freeze Out

The transverse momentum spectra of different types of particles, π±, K±, p and p¯, produced at mid-(pseudo)rapidity in different centrality lead–lead (Pb–Pb) collisions at 2.76 TeV; proton–lead (p–Pb) collisions at 5.02 TeV; xenon–xenon (Xe–Xe) collisions at 5.44 TeV; and proton–proton (p–p) collisions at 0.9, 2.76, 5.02, 7 and 13 TeV, were analyzed by the blast-wave model with fluctuations. With the experimental data measured by the ALICE and CMS Collaborations at the Large Hadron Collider (LHC), the kinetic freeze-out temperature, transverse flow velocity and proper time were extracted from fitting the transverse momentum spectra. In nucleus–nucleus (A–A) and proton–nucleus (p–A) collisions, the three parameters decrease with the decrease of event centrality from central to peripheral, indicating higher degrees of excitation, quicker expansion velocities and longer evolution times for central collisions. In p–p collisions, the kinetic freeze-out temperature is nearly invariant with the increase of energy, though the transverse flow velocity and proper time increase slightly, in the considered energy range.

scholarly journals Study of Proton, Deuteron, and Triton at 54.4 GeV

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
M. Waqas ◽  
G. X. Peng
Keyword(s):  
Transverse Momentum ◽  
Flow Velocity ◽  
Star Collaboration ◽  
Wave Model ◽  
Transverse Flow ◽  
Peripheral Collisions ◽  
Momentum Spectra ◽  
Transverse Momentum Spectra ◽  
Transverse Flow Velocity ◽  
Freeze Out

Transverse momentum spectra of proton, deuteron, and triton in gold-gold (Au-Au) collisions at 54.4 GeV are analyzed in different centrality bins by the blast wave model with Tsallis statistics. The model results are approximately in agreement with the experimental data measured by STAR Collaboration in special transverse momentum ranges. We extracted the kinetic freeze-out temperature, transverse flow velocity, and freeze-out volume from the transverse momentum spectra of the particles. It is observed that the kinetic freeze-out temperature is increasing from the central to peripheral collisions. However, the transverse flow velocity and freeze-out volume decrease from the central to peripheral collisions. The present work reveals the mass dependent kinetic freeze-out scenario and volume differential freeze-out scenario in collisions at STAR Collaboration. In addition, parameter q characterizes the degree of nonequilibrium of the produced system, and it increases from the central to peripheral collisions and increases with mass .

scholarly journals Kinetic Freeze-Out Temperature and Transverse Flow Velocity in Au-Au Collisions at RHIC-BES Energies

2020 ◽  
Vol 2020 ◽  
pp. 1-14 ◽  
Author(s):  
Muhammad Waqas ◽  
Bao-Chun Li
Keyword(s):  
Transverse Momentum ◽  
Flow Velocity ◽  
Star Collaboration ◽  
Wave Model ◽  
Heavy Ion ◽  
Transverse Flow ◽  
Relativistic Heavy Ion Collider ◽  
Beam Energy Scan ◽  
Transverse Flow Velocity ◽  
Freeze Out

By using the method of data-driven reanalysis, the midrapidity transverse momentum pT spectra of charged hadrons (π+, K+, and p) produced in central and peripheral gold-gold (Au-Au) collisions from the Beam Energy Scan (BES) program at the Relativistic Heavy Ion Collider (RHIC) are fitted by using the blast-wave model with the Boltzmann-Gibbs statistics. The model results are in agreement with the experimental data measured by the STAR Collaboration at the RHIC-BES energies. We observe that the kinetic freeze-out temperature T0, transverse flow velocity βT, mean transverse momentum pT, and initial temperature Ti increase with collision energy as well as with event centrality.

scholarly journals Study of Kinetic Freeze-Out Parameters as a Function of Rapidity in pp Collisions at CERN SPS Energies

Entropy ◽  
2021 ◽  
Vol 23 (10) ◽  
pp. 1363
Author(s):  
Muhammad Waqas ◽  
Huai-Min Chen ◽  
Guang-Xiong Peng ◽  
Abd Al Karim Haj Ismail ◽  
Muhammad Ajaz ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Center Of Mass ◽  
Wave Model ◽  
Transverse Flow ◽  
Proton Proton ◽  
Momentum Spectra ◽  
Transverse Momentum Spectra ◽  
Energy Dependent ◽  
Transverse Flow Velocity ◽  
Freeze Out

We used the blast wave model with the Boltzmann–Gibbs statistics and analyzed the experimental data measured by the NA61/SHINE Collaboration in inelastic (INEL) proton–proton collisions at different rapidity slices at different center-of-mass energies. The particles used in this study were π+, π−, K+, K− and p¯. We extracted the kinetic freeze-out temperature, transverse flow velocity, and kinetic freeze-out volume from the transverse momentum spectra of the particles. We observed that the kinetic freeze-out temperature is rapidity and energy dependent, while the transverse flow velocity does not depend on them. Furthermore, we observed that the kinetic freeze-out volume is energy dependent, but it remains constant with changing the rapidity. We also observed that all three parameters are mass dependent. In addition, with the increase of mass, the kinetic freeze-out temperature increases, and the transverse flow velocity, as well as kinetic freeze-out volume decrease.

scholarly journals Study of Dependence of Kinetic Freezeout Temperature on the Production Cross-Section of Particles in Various Centrality Intervals in Au–Au and Pb–Pb Collisions at High Energies

Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 488
Author(s):  
Muhammad Waqas ◽  
Guang-Xiong Peng
Keyword(s):  
Transverse Momentum ◽  
Flow Velocity ◽  
Production Cross ◽  
Center Of Mass ◽  
Wave Model ◽  
Transverse Flow ◽  
Peripheral Collisions ◽  
Momentum Spectra ◽  
Transverse Momentum Spectra ◽  
Transverse Flow Velocity

Transverse momentum spectra of π+, p, Λ, Ξ or Ξ¯+, Ω or Ω¯+ and deuteron (d) in different centrality intervals in nucleus–nucleus collisions at the center of mass energy are analyzed by the blast wave model with Boltzmann Gibbs statistics. We extracted the kinetic freezeout temperature, transverse flow velocity and kinetic freezeout volume from the transverse momentum spectra of the particles. It is observed that the non-strange and strange (multi-strange) particles freezeout separately due to different reaction cross-sections. While the freezeout volume and transverse flow velocity are mass dependent, they decrease with the resting mass of the particles. The present work reveals the scenario of a double kinetic freezeout in nucleus–nucleus collisions. Furthermore, the kinetic freezeout temperature and freezeout volume are larger in central collisions than peripheral collisions. However, the transverse flow velocity remains almost unchanged from central to peripheral collisions.

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