Jean Cleymans
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The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
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Jean Cleymans has a total of 1000 co-authors. Here are the top co-authors by number of shared publications:
- Krzysztof Redlich
National Centre for Nuclear Research
50 shared publications R. Sahoo
Indian Institute of Technology Indore
41 shared publications- Alberto M. Gago
Pontificia Universidad Católica del Perú
40 shared publications B. Hippolyte
Université de Strasbourg, CNRS, IPHC UMR 7178
40 shared publications- Biswarup Paul
Homi Bhabha National Institute
40 shared publications - Chinorat Kobdaj
Suranaree University of Technology
40 shared publications
Latest Publications
- 1 July 2021
- Published by Pleiades Publishing Ltd in Physics of Particles and Nuclei
- Vol. 52 (4) , 497-500
NICA: Theoretical Overview
There are strong reasons to bleive that the energy region covered by the Nuclotron-based Ion Collider fAcility (NICA) is an extremely interesting one. We present an overview of theoretical proposals in relativistic heavy ion collisions and show where more and better measurements are needed. The theoretical understanding can be clarified by covering the energy region available to NICA. It would be helpful to determine the strangeness content by covering the full phase space (\(4\pi \)) to determine the thermodynamic parameters.- 1 July 2021
- Published by Pleiades Publishing Ltd in Physics of Particles and Nuclei
- Vol. 52 (4) , 497-500
NICA: Theoretical Overview
There are strong reasons to bleive that the energy region covered by the Nuclotron-based Ion Collider fAcility (NICA) is an extremely interesting one. We present an overview of theoretical proposals in relativistic heavy ion collisions and show where more and better measurements are needed. The theoretical understanding can be clarified by covering the energy region available to NICA. It would be helpful to determine the strangeness content by covering the full phase space (\(4\pi \)) to determine the thermodynamic parameters.- Open Access
Tsallis Statistics in High Energy Physics: Chemical and Thermal Freeze-Outs
We present an overview of a proposal in relativistic proton-proton () collisions emphasizing the thermal or kinetic freeze-out stage in the framework of the Tsallis distribution. In this paper we take into account the chemical potential present in the Tsallis distribution by following a two step procedure. In the first step we used the redudancy present in the variables such as the system temperature, T, volume, V, Tsallis exponent, q, chemical potential, , and performed all fits by effectively setting to zero the chemical potential. In the second step the value q is kept fixed at the value determined in the first step. This way the complete set of variables and can be determined. The final results show a weak energy dependence in collisions at the centre-of-mass energy TeV to 13 TeV. The chemical potential at kinetic freeze-out shows an increase with beam energy. This simplifies the description of the thermal freeze-out stage in collisions as the values of T and of the freeze-out radius R remain constant to a good approximation over a wide range of beam energies.Open AccessTsallis Statistics in High Energy Physics: Chemical and Thermal Freeze-Outs
We present an overview of a proposal in relativistic proton-proton () collisions emphasizing the thermal or kinetic freeze-out stage in the framework of the Tsallis distribution. In this paper we take into account the chemical potential present in the Tsallis distribution by following a two step procedure. In the first step we used the redudancy present in the variables such as the system temperature, T, volume, V, Tsallis exponent, q, chemical potential, , and performed all fits by effectively setting to zero the chemical potential. In the second step the value q is kept fixed at the value determined in the first step. This way the complete set of variables and can be determined. The final results show a weak energy dependence in collisions at the centre-of-mass energy TeV to 13 TeV. The chemical potential at kinetic freeze-out shows an increase with beam energy. This simplifies the description of the thermal freeze-out stage in collisions as the values of T and of the freeze-out radius R remain constant to a good approximation over a wide range of beam energies. - Open AccessEvent multiplicity, transverse momentum and energy dependence of charged particle production, and system thermodynamics in $pp$ collisions at the Large Hadron ColliderIn the present work, we study the recent collision energy and multiplicity dependence of the charged particle transverse momentum spectra as measured by the ALICE collaboration in $pp$ collisions at $\sqrt{s}$ = 5.02 and 13 TeV using the non-extensive Tsallis distribution and the Boltzmann-Gibbs Blast Wave (BGBW) model. A thermodynamically consistent form of the Tsallis distribution is used to extract the kinetic freeze-out parameters from the transverse momentum spectra of charged particles at mid-rapidity. In addition, a comprehensive study of fitting range dependence of transverse momentum spectra on the freeze-out parameters is done using Tsallis statistics. The applicability of BGBW model is verified by fitting the transverse momentum spectra of the bulk part ($\sim 2.5~ {\rm GeV}/c$)for both 5.02 and 13 TeV energies and also in different multiplicity classes. The radial flow, $<\beta>$ is almost independent of collision energy and multiplicity whereas the behavior of kinetic freeze-out temperature significantly depends on multiplicity classes. It is found that the Tsallis distribution generally leads to a better description for the complete transverse momentum spectra whereas the BGBW model explains the bulk part of the system.Open AccessEvent multiplicity, transverse momentum and energy dependence of charged particle production, and system thermodynamics in $pp$ collisions at the Large Hadron ColliderIn the present work, we study the recent collision energy and multiplicity dependence of the charged particle transverse momentum spectra as measured by the ALICE collaboration in $pp$ collisions at $\sqrt{s}$ = 5.02 and 13 TeV using the non-extensive Tsallis distribution and the Boltzmann-Gibbs Blast Wave (BGBW) model. A thermodynamically consistent form of the Tsallis distribution is used to extract the kinetic freeze-out parameters from the transverse momentum spectra of charged particles at mid-rapidity. In addition, a comprehensive study of fitting range dependence of transverse momentum spectra on the freeze-out parameters is done using Tsallis statistics. The applicability of BGBW model is verified by fitting the transverse momentum spectra of the bulk part ($\sim 2.5~ {\rm GeV}/c$)for both 5.02 and 13 TeV energies and also in different multiplicity classes. The radial flow, $<\beta>$ is almost independent of collision energy and multiplicity whereas the behavior of kinetic freeze-out temperature significantly depends on multiplicity classes. It is found that the Tsallis distribution generally leads to a better description for the complete transverse momentum spectra whereas the BGBW model explains the bulk part of the system.
- Open Access
- 3 April 2020
- Published by IOP Publishing in Journal of Physics G: Nuclear and Particle Physics
- Vol. 47 (5) , 055111
Event multiplicity, transverse momentum and energy dependence of charged particle production, and system thermodynamics in pp collisions at the Large Hadron Collider
In the present work, we study the recent collision energy and multiplicity dependence of the charged particle transverse momentum spectra as measured by the ALICE collaboration in pp collisions at s = 5.02 and 13 TeV using the non-extensive Tsallis distribution and the Boltzmann–Gibbs blast wave (BGBW) model. A thermodynamically consistent form of the Tsallis distribution is used to extract the kinetic freeze-out parameters from the transverse momentum spectra of charged particles at mid-rapidity. In addition, a comprehensive study of fitting range dependence of transverse momentum spectra on the freeze-out parameters is done using Tsallis statistics. The applicability of BGBW model is verified by fitting the transverse momentum spectra of the bulk part (∼2.5 GeV/ c ) for both 5.02 and 13 TeV energies and also in different multiplicity classes. The radial flow, 〈 β 〉 is almost independent of collision energy and multiplicity whereas the behavior of kinetic freeze-out temperature significantly depends on multiplicity classes. It is found that the Tsallis distribution generally leads to a better description for the complete transverse momentum spectra whereas the BGBW model explains the bulk part of the system.
- 3 April 2020
- Published by IOP Publishing in Journal of Physics G: Nuclear and Particle Physics
- Vol. 47 (5) , 055111
Open AccessEvent multiplicity, transverse momentum and energy dependence of charged particle production, and system thermodynamics in pp collisions at the Large Hadron Collider
In the present work, we study the recent collision energy and multiplicity dependence of the charged particle transverse momentum spectra as measured by the ALICE collaboration in pp collisions at s = 5.02 and 13 TeV using the non-extensive Tsallis distribution and the Boltzmann–Gibbs blast wave (BGBW) model. A thermodynamically consistent form of the Tsallis distribution is used to extract the kinetic freeze-out parameters from the transverse momentum spectra of charged particles at mid-rapidity. In addition, a comprehensive study of fitting range dependence of transverse momentum spectra on the freeze-out parameters is done using Tsallis statistics. The applicability of BGBW model is verified by fitting the transverse momentum spectra of the bulk part (∼2.5 GeV/ c ) for both 5.02 and 13 TeV energies and also in different multiplicity classes. The radial flow, 〈 β 〉 is almost independent of collision energy and multiplicity whereas the behavior of kinetic freeze-out temperature significantly depends on multiplicity classes. It is found that the Tsallis distribution generally leads to a better description for the complete transverse momentum spectra whereas the BGBW model explains the bulk part of the system.
- 17 March 2020
- Published by Springer Nature
- p. 65-70
The Physics Case for the FAIR/NICA Energy Region
- 1 February 2020
- Published by IOP Publishing in Journal of Physics G: Nuclear and Particle Physics
- Vol. 47 (4) , 045001
Energy density at kinetic freeze-out in Pb–Pb collisions at the LHC using the Tsallis distribution
The thermodynamic parameters like energy density, pressure, entropy density, temperature and particle density are determined from the transverse momentum distributions of charged hadrons in Pb–Pb collisions at the LHC. The results show a clear increase with the centrality and the beam energy in all parameters. It is determined that in the final freeze-out stage the energy density reaches a value of about 0.039 GeV fm −3 for the most central collisions at s NN = 5.02 TeV . This is less than that at chemical freeze-out where the energy density is about 0.36 GeV fm −3 . This decrease approximately follows a T 4 law. The results for the pressure and entropy density are also presented for each centrality class at s NN = 2.76 and 5.02 TeV.
- 1 February 2020
- Published by IOP Publishing in Journal of Physics G: Nuclear and Particle Physics
- Vol. 47 (4) , 045001
Energy density at kinetic freeze-out in Pb–Pb collisions at the LHC using the Tsallis distribution
The thermodynamic parameters like energy density, pressure, entropy density, temperature and particle density are determined from the transverse momentum distributions of charged hadrons in Pb–Pb collisions at the LHC. The results show a clear increase with the centrality and the beam energy in all parameters. It is determined that in the final freeze-out stage the energy density reaches a value of about 0.039 GeV fm −3 for the most central collisions at s NN = 5.02 TeV . This is less than that at chemical freeze-out where the energy density is about 0.36 GeV fm −3 . This decrease approximately follows a T 4 law. The results for the pressure and entropy density are also presented for each centrality class at s NN = 2.76 and 5.02 TeV.
- Open Access
- 11 December 2019
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2019 (12) , 92
Measurement of prompt D0, D+, D*+, and $ {\mathrm{D}}_{\mathrm{S}}^{+} $ production in p–Pb collisions at $ \sqrt{{\mathrm{s}}_{\mathrm{NN}}} $ = 5.02 TeVThe measurement of the production of prompt D0, D+, D*+, and $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ mesons in proton–lead (p–Pb) collisions at the centre-of-mass energy per nucleon pair of $$ \sqrt{s_{\mathrm{NN}}} $$ = 5.02 TeV, with an integrated luminosity of 292 ± 11 μb −1, are reported. Differential production cross sections are measured at mid-rapidity (−0.96 < y cms < 0.04) as a function of transverse momentum (p T) in the intervals 0 < p T < 36 GeV/c for D0, 1 < p T < 36 GeV/c for D+ and D*+, and 2 < p T < 24 GeV/c for D+ mesons. For each species, the nuclear modification factor R pPb is calculated as a function of p T using a proton-proton (pp) ref- erence measured at the same collision energy. The results are compatible with unity in the whole p T range. The average of the non-strange D mesons R pPb is compared with theoretical model predictions that include initial-state effects and parton transport model predictions. The p T dependence of the D0, D+, and D*+ nuclear modification factors is also reported in the interval 1 < p T < 36 GeV/c as a function of the collision centrality, and the central-to-peripheral ratios are computed from the D-meson yields measured in different centrality classes. The results are further compared with charged-particle measurements and a similar trend is observed in all the centrality classes. The ratios of the p T-differential cross sections of D0, D+, D*+, and $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ mesons are also reported. The $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ and D+ yields are compared as a function of the charged-particle multiplicity for several p T intervals. No modification in the relative abundances of the four species is observed with respect to pp collisions within the statistical and systematic uncertainties.- 11 December 2019
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2019 (12) , 92
Open AccessMeasurement of prompt D0, D+, D*+, and $ {\mathrm{D}}_{\mathrm{S}}^{+} $ production in p–Pb collisions at $ \sqrt{{\mathrm{s}}_{\mathrm{NN}}} $ = 5.02 TeVThe measurement of the production of prompt D0, D+, D*+, and $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ mesons in proton–lead (p–Pb) collisions at the centre-of-mass energy per nucleon pair of $$ \sqrt{s_{\mathrm{NN}}} $$ = 5.02 TeV, with an integrated luminosity of 292 ± 11 μb −1, are reported. Differential production cross sections are measured at mid-rapidity (−0.96 < y cms < 0.04) as a function of transverse momentum (p T) in the intervals 0 < p T < 36 GeV/c for D0, 1 < p T < 36 GeV/c for D+ and D*+, and 2 < p T < 24 GeV/c for D+ mesons. For each species, the nuclear modification factor R pPb is calculated as a function of p T using a proton-proton (pp) ref- erence measured at the same collision energy. The results are compatible with unity in the whole p T range. The average of the non-strange D mesons R pPb is compared with theoretical model predictions that include initial-state effects and parton transport model predictions. The p T dependence of the D0, D+, and D*+ nuclear modification factors is also reported in the interval 1 < p T < 36 GeV/c as a function of the collision centrality, and the central-to-peripheral ratios are computed from the D-meson yields measured in different centrality classes. The results are further compared with charged-particle measurements and a similar trend is observed in all the centrality classes. The ratios of the p T-differential cross sections of D0, D+, D*+, and $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ mesons are also reported. The $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ and D+ yields are compared as a function of the charged-particle multiplicity for several p T intervals. No modification in the relative abundances of the four species is observed with respect to pp collisions within the statistical and systematic uncertainties. - Open Access
- 10 December 2019
- Published by Springer Nature in The European Physical Journal C
- Vol. 79 (12) , 998
Erratum to: Insight into particle production mechanisms via angular correlations of identified particles in pp collisions at $\sqrt{s}=7$ TeVThis document corrects two errors in Eur. Phys. J. C77 (2017) no. 8, 56: the incorrect referencing of Fig. 1 labels in three paragraphs in the results section and a missing acknowledgements section.
- 10 December 2019
- Published by Springer Nature in The European Physical Journal C
- Vol. 79 (12) , 998
Open AccessErratum to: Insight into particle production mechanisms via angular correlations of identified particles in pp collisions at $\sqrt{s}=7$ TeVThis document corrects two errors in Eur. Phys. J. C77 (2017) no. 8, 56: the incorrect referencing of Fig. 1 labels in three paragraphs in the results section and a missing acknowledgements section.
- Open Access
- 17 October 2019
- Published by Springer Nature in The European Physical Journal C
- Vol. 79 (10) , 857
Charged-particle production as a function of multiplicity and transverse spherocity in pp collisions at $ \sqrt{\mathbf{s}} =\mathbf{5.02}$ and 13 TeVWe present a study of the inclusive charged-particle transverse momentum ( $$p_{\mathrm{T}}$$ ) spectra as a function of charged-particle multiplicity density at mid-pseudorapidity, $$\mathrm{d}N_{\mathrm{ch}}/\mathrm{d}\eta $$ , in pp collisions at $$\sqrt{s}=5.02$$ and 13 TeV covering the kinematic range $$|\eta |<0.8$$ and $$0.15<p_{\mathrm{T}} <20$$ GeV/c. The results are presented for events with at least one charged particle in $$|\eta |<1$$ (INEL $$\,>0$$ ). The $$p_\mathrm{T}$$ spectra are reported for two multiplicity estimators covering different pseudorapidity regions. The $$p_{\mathrm{T}}$$ spectra normalized to that for INEL $$\,>0$$ show little energy dependence. Moreover, the high- $$p_{\mathrm{T}}$$ yields of charged particles increase faster than the charged-particle multiplicity density. The average $${ p}_{\mathrm{T}}$$ as a function of multiplicity and transverse spherocity is reported for pp collisions at $$\sqrt{s}=13$$ TeV. For low- (high-) spherocity events, corresponding to jet-like (isotropic) events, the average $$p_\mathrm{T}$$ is higher (smaller) than that measured in INEL $$\,>0$$ pp collisions. Within uncertainties, the functional form of $$\langle p_{\mathrm{T}} \rangle (N_{\mathrm{ch}})$$ is not affected by the spherocity selection. While EPOS LHC gives a good description of many features of data, PYTHIA overestimates the average $$p_{\mathrm{T}}$$ in jet-like events.- 17 October 2019
- Published by Springer Nature in The European Physical Journal C
- Vol. 79 (10) , 857
Open AccessCharged-particle production as a function of multiplicity and transverse spherocity in pp collisions at $ \sqrt{\mathbf{s}} =\mathbf{5.02}$ and 13 TeVWe present a study of the inclusive charged-particle transverse momentum ( $$p_{\mathrm{T}}$$ ) spectra as a function of charged-particle multiplicity density at mid-pseudorapidity, $$\mathrm{d}N_{\mathrm{ch}}/\mathrm{d}\eta $$ , in pp collisions at $$\sqrt{s}=5.02$$ and 13 TeV covering the kinematic range $$|\eta |<0.8$$ and $$0.15<p_{\mathrm{T}} <20$$ GeV/c. The results are presented for events with at least one charged particle in $$|\eta |<1$$ (INEL $$\,>0$$ ). The $$p_\mathrm{T}$$ spectra are reported for two multiplicity estimators covering different pseudorapidity regions. The $$p_{\mathrm{T}}$$ spectra normalized to that for INEL $$\,>0$$ show little energy dependence. Moreover, the high- $$p_{\mathrm{T}}$$ yields of charged particles increase faster than the charged-particle multiplicity density. The average $${ p}_{\mathrm{T}}$$ as a function of multiplicity and transverse spherocity is reported for pp collisions at $$\sqrt{s}=13$$ TeV. For low- (high-) spherocity events, corresponding to jet-like (isotropic) events, the average $$p_\mathrm{T}$$ is higher (smaller) than that measured in INEL $$\,>0$$ pp collisions. Within uncertainties, the functional form of $$\langle p_{\mathrm{T}} \rangle (N_{\mathrm{ch}})$$ is not affected by the spherocity selection. While EPOS LHC gives a good description of many features of data, PYTHIA overestimates the average $$p_{\mathrm{T}}$$ in jet-like events. - Open Access
- 7 October 2019
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2019 (10) , 84
Inclusive J/ψ production at mid-rapidity in pp collisions at $ \sqrt{s} $ = 5.02 TeVInclusive J/ψ production is studied in minimum-bias proton-proton collisions at a centre-of-mass energy of $$ \sqrt{s} $$ = 5.02 TeV by ALICE at the CERN LHC. The measurement is performed at mid-rapidity (|y| < 0.9) in the dielectron decay channel down to zero transverse momentum p T, using a data sample corresponding to an integrated luminosity of L int = 19.4 ± 0.4 nb −1. The measured p T-integrated inclusive J/ψ production cross sec- tion is dσ/dy = 5.64 ± 0.22(stat.) ± 0.33(syst.) ± 0.12(lumi.) μb. The p T-differential cross section d2 σ/dp Tdy is measured in the p T range 0–10 GeV/c and compared with state-of- the-art QCD calculations. The J/ψ 〈p T〉 and $$ \left\langle {p}_{\mathrm{T}}^2\right\rangle $$ are extracted and compared with results obtained at other collision energies.- 7 October 2019
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2019 (10) , 84
Open AccessInclusive J/ψ production at mid-rapidity in pp collisions at $ \sqrt{s} $ = 5.02 TeVInclusive J/ψ production is studied in minimum-bias proton-proton collisions at a centre-of-mass energy of $$ \sqrt{s} $$ = 5.02 TeV by ALICE at the CERN LHC. The measurement is performed at mid-rapidity (|y| < 0.9) in the dielectron decay channel down to zero transverse momentum p T, using a data sample corresponding to an integrated luminosity of L int = 19.4 ± 0.4 nb −1. The measured p T-integrated inclusive J/ψ production cross sec- tion is dσ/dy = 5.64 ± 0.22(stat.) ± 0.33(syst.) ± 0.12(lumi.) μb. The p T-differential cross section d2 σ/dp Tdy is measured in the p T range 0–10 GeV/c and compared with state-of- the-art QCD calculations. The J/ψ 〈p T〉 and $$ \left\langle {p}_{\mathrm{T}}^2\right\rangle $$ are extracted and compared with results obtained at other collision energies.