Extracting temperature and transverse flow by fitting transverse mass spectra and HBT radii together

Single particle transverse mass spectra and HBT radii of identical pion and identical kaon are analyzed with a blast-wave parametrization under the assumptions of local thermal equilibrium and transverse expansion. Under the assumptions, temperature parameter [Formula: see text] and transverse expansion rapidity [Formula: see text] are sensitive to the shapes of transverse mass [Formula: see text] spectrum and HBT radius [Formula: see text]. Negative and positive correlations between [Formula: see text] and [Formula: see text] are observed by fitting [Formula: see text] spectrum and HBT radius [Formula: see text], respectively. For a Monte Carlo simulation using the blast-wave function, [Formula: see text] and [Formula: see text] are extracted by fitting [Formula: see text] spectra and HBT radii together utilizing a combined optimization function [Formula: see text]. With this method, [Formula: see text] and [Formula: see text] of the Monte Carlo sources can be extracted. Using this method for A Multi-Phase Transport (AMPT) model at Relativistic Heavy Ion Collider (RHIC) energy, the differences of [Formula: see text] and [Formula: see text] between pion and kaon are observed obviously, and the tendencies of [Formula: see text] and [Formula: see text] versus collision energy [Formula: see text] are similar with the results extracted directly from the AMPT model.

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Studying Strangeness Production with HADES

EPJ Web of Conferences ◽

10.1051/epjconf/201817101001 ◽

2018 ◽

Vol 171 ◽

pp. 01001

Author(s):

Heidi Schuldes

Keyword(s):

Mass Spectra ◽

Threshold Energy ◽

Heavy Ion ◽

Spectral Shape ◽

Transverse Mass ◽

Fixed Target ◽

Fixed Target Experiments ◽

Ion Collisions ◽

Global Properties ◽

The World

The High-Acceptance DiElectron Spectrometer (HADES) operates in the 1 - 2A GeV energy regime in fixed target experiments to explore baryon-rich strongly interacting matter in heavy-ion collisions at moderate temperatures with rare and penetrating probes. We present results on the production of strange hadrons below their respective NN threshold energy in Au+Au collisions at 1.23A GeV ([see formula in PDF] = 2.4 GeV). Special emphasis is put on the enhanced feed-down contribution of ϕ mesons to the inclusive yield of K- and its implication on the measured spectral shape of K-. Furthermore, we investigate global properties of the system, confronting the measured hadron yields and transverse mass spectra with a Statistical Hadronization Model (SHM) and a blastwave parameterization, respectively. These supplement the world data of the chemical and kinetic freeze-out temperatures.

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Average transverse expansion velocities and global freeze-out temperatures in central Cu + Cu, Au + Au, and Pb + Pb collisions at high energies at RHIC and LHC

Modern Physics Letters A ◽

10.1142/s0217732320501151 ◽

2020 ◽

Vol 35 (14) ◽

pp. 2050115 ◽

Cited By ~ 1

Author(s):

Khusniddin K. Olimov ◽

Shakhnoza Z. Kanokova ◽

Kosim Olimov ◽

Kadyr G. Gulamov ◽

Bekhzod S. Yuldashev ◽

...

Keyword(s):

Blast Wave ◽

Heavy Ion Collisions ◽

Wave Model ◽

Heavy Ion ◽

Transverse Flow ◽

Collision System ◽

Transverse Expansion ◽

Ion Collisions ◽

Charged Pions ◽

Freeze Out

The experimental invariant transverse momentum [Formula: see text] spectra of the charged pions and kaons, protons and antiprotons, produced at midrapidity in central (0–10%) Au[Formula: see text]Au collisions at [Formula: see text], central (0–10%) Cu[Formula: see text]Cu collisions at [Formula: see text], central (0–10%) Au[Formula: see text]Au collisions at [Formula: see text], and central (0–5%) Pb[Formula: see text]Pb collisions at [Formula: see text], measured by BRAHMS, STAR and ALICE collaborations, were analyzed using three different transverse expansion (blast-wave) models: Siemens–Rasmussen blast-wave model, Simple transverse flow model, and Simplified (hydro-inspired) blast-wave model of Schnedermann et al. Combined (simultaneous) minimum [Formula: see text] fits of the experimental invariant [Formula: see text] spectra of the charged pions and kaons, protons and antiprotons with the above three model functions were conducted, using the identical selected optimal fitting ranges in [Formula: see text] in each studied collision system, and the values of the average transverse expansion velocity [Formula: see text] and global kinetic freeze-out temperature [Formula: see text] and their dependencies on the collision system [Formula: see text] and [Formula: see text] were extracted. The combined (simultaneous) fits using Hagedorn formula with the (embedded) simple transverse flow describe well the experimental invariant [Formula: see text] spectra of the charged pions, kaons, protons and antiprotons in the whole measured range in region [Formula: see text] in the analyzed central heavy ion collisions at RHIC and LHC, reproducing qualitatively well all the established dependencies of the parameters [Formula: see text] and [Formula: see text] on the collision system [Formula: see text] and [Formula: see text]. The obtained results were compared with those of the previous analyses of high energy heavy ion collisions.

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Re-hardening of hadron transverse mass spectra in relativistic heavy-ion collisions

Pramana ◽

10.1007/bf02704779 ◽

2006 ◽

Vol 66 (5) ◽

pp. 809-816

Author(s):

P. K. Sahu ◽

N. Otuka ◽

M. Isse ◽

Y. Nara ◽

A. Ohnishi

Keyword(s):

Heavy Ion Collisions ◽

Mass Spectra ◽

Heavy Ion ◽

Relativistic Heavy Ion Collisions ◽

Transverse Mass ◽

Ion Collisions

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Transverse-mass spectra in heavy-ion collisions at energiesElab=2−160GeV/nucleon

Physical Review C ◽

10.1103/physrevc.78.064902 ◽

2008 ◽

Vol 78 (6) ◽

Cited By ~ 9

Author(s):

Yu. B. Ivanov ◽

V. N. Russkikh

Keyword(s):

Heavy Ion Collisions ◽

Mass Spectra ◽

Heavy Ion ◽

Transverse Mass ◽

Ion Collisions

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Excitation Functions of Related Parameters from Transverse Momentum (Mass) Spectra in High-Energy Collisions

Advances in High Energy Physics ◽

10.1155/2020/5356705 ◽

2020 ◽

Vol 2020 ◽

pp. 1-21

Author(s):

Li-Li Li ◽

Fu-Hu Liu ◽

Muhammad Waqas ◽

Rasha Al-Yusufi ◽

Altaf Mujear

Keyword(s):

Transverse Momentum ◽

Mass Spectra ◽

Hadron Collider ◽

Heavy Ion ◽

High Energy ◽

Relativistic Heavy Ion Collider ◽

Excitation Functions ◽

Charged Pions ◽

Standard Distribution ◽

Freeze Out

Transverse momentum (mass) spectra of positively and negatively charged pions and of positively and negatively charged kaons, protons, and antiprotons produced at mid-(pseudo)rapidity in various collisions at high energies are analyzed in this work. The experimental data measured in central gold-gold, central lead-lead, and inelastic proton-proton collisions by several international collaborations are studied. The (two-component) standard distribution is used to fit the data and extract the excitation function of effective temperature. Then, the excitation functions of kinetic freeze-out temperature, transverse flow velocity, and initial temperature are obtained. In the considered collisions, the four parameters increase with the increase of collision energy in general, and the kinetic freeze-out temperature appears at the trend of saturation at the top Relativistic Heavy Ion Collider and the Large Hadron Collider.

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Generalized scaling of the transverse mass spectrum at the relativistic heavy-ion collider

Nuclear Physics A ◽

10.1016/s0375-9474(02)00677-2 ◽

2002 ◽

Vol 705 (3-4) ◽

pp. 494-507 ◽

Cited By ~ 55

Author(s):

Jürgen Schaffner-Bielich ◽

Dmitri Kharzeev ◽

Larry McLerran ◽

Raju Venugopalan

Keyword(s):

Mass Spectrum ◽

Heavy Ion ◽

Transverse Mass ◽

Relativistic Heavy Ion Collider

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TRANSVERSE MASS SPECTRA AND RAPIDITY DISTRIBUTIONS OF K+ IN NI–NI COLLISIONS AT 1.93 A GeV

Modern Physics Letters A ◽

10.1142/s0217732313500703 ◽

2013 ◽

Vol 28 (16) ◽

pp. 1350070 ◽

Cited By ~ 1

Author(s):

PORNRAD SRISAWAD ◽

ANANYA SUKSRI ◽

SIRICHAI PHOLWIANG ◽

ANTONY HARFIELD ◽

YU-MING ZHENG ◽

...

Keyword(s):

Mass Spectra ◽

Heavy Ion ◽

Hadronic Matter ◽

Transverse Mass ◽

Quantum Molecular Dynamics ◽

Medium Effects ◽

Nuclear Equation Of State ◽

Intermediate Energies ◽

Ion Collisions ◽

Rapidity Distributions

In heavy-ion collisions, the production of kaon at intermediate energies provides a sensitive probe to study the in-medium properties of hadrons. Properties of kaons in dense hadronic matter are important for a better understanding of both the possible restoration of chiral symmetry in dense hadronic matter and the properties of nuclear matter at high densities. In this paper, the in-medium effects and nuclear equation of state (EOS) are studied by analyzing the transverse mass spectra and rapidity distributions of the produced K+ mesons in [Formula: see text] collisions at 1.93 A GeV using the quantum molecular dynamics (QMD) model. The work reveals that the KaoS data favor a repulsive in-medium K+N potential (its value at saturation density ρ0 is (Uk(ρ0) ≈30 MeV ). It is also found that the transverse mass spectra and rapidity distributions of K+ mesons are sensitive to the nuclear EOS.

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