On Descriptions of Particle Transverse Momentum Spectra in High Energy Collisions

Abstract

Transverse momentum (mass) spectra of positively and negatively charged pions (π + and π − ), positively and negatively charged kaons (K + and K − ), protons and antiprotons (p andp) produced at mid-(pseudo)rapidity in various collisions at high energies are analyzed in this work. The experimental data measured in central gold-gold (Au-Au) collisions at the Alternating Gradient Synchrotron (AGS) by the E866, E895, and E802 Collaborations and at the Relativistic Heavy Ion Collider (RHIC) by the STAR and PHENIX Collaborations, in central lead-lead (Pb-Pb) collisions at the Super Proton Synchrotron (SPS) by the NA49 Collaboration and at the Large Hadron Collider (LHC) by the ALICE Collaboration, as well as in inelastic (INEL) proton-proton (pp) collisions at the SPS by the NA61/SHINE Collaboration, at the RHIC by the PHENIX Collaboration, and at the LHC by the CMS Collaboration are studied. The (two-component) standard distribution is used to fit the data and the excitation function of effective temperature is obtained. Then, the excitation functions of kinetic freeze-out temperature, transverse flow velocity, and initial temperature are extracted. In the considered collisions, the four parameters increase with the increase of collision energy in general, and the kinetic freeze-out temperature appears the trend of saturation at the top RHIC and LHC.

Initial- and Final-State Temperatures of Emission Source from Differential Cross-Section in Squared Momentum Transfer in High-Energy Collisions

“…In fact, the two-, three-, or multicomponent standard distribution can be fitted satisfactorily by the Tsallis distribution with q > 1, because the standard distribution is narrower than the Tsallis distribution [68]. In particular, the standard distribution is equivalent to the Tsallis distribution with q = 1.…”

Kinetic freeze-out temperatures in central and peripheral collisions: which one is larger?

“…In detail, the alternative method can be divided into a few sub-methods due to different distributions being used. Generally, we are inclined to use the standard and Tsallis distributions in the alternative method due to the standard distribution being closest to the ideal gas model in thermodynamics, and the Tsallis distribution describing a wide spectrum which needs two-or three-component standard distribution to be fitted [21].…”

Study of Production of (Anti-)deuteron Observed in Au+Au Collisions at s NN

“…The model used in the present work is the multisource thermal model [21][22][23]. In this model, many emission sources are formed in high-energy nucleus-nucleus collisions.…”

“…In this model, many emission sources are formed in high-energy nucleus-nucleus collisions. The different distributions can describe the emission sources and particle spectra, such as the Tsallis distribution, the standard (Boltzmann, Fermi-Dirac, and Bose-Einstein) distributions, the Tsallis+standard distributions [24][25][26][27][28][29], and the Erlang distribution [21]. The Tsallis distribution can be described by two or three standard distributions.…”