Indication of transverse radial flow in high-multiplicity proton-proton collisions at the Large Hadron Collider

Abstract

We analyze the measured spectra of ${\pi }^{\pm }$, $K^{\pm }$, $p$($\bar{p}$) in $pp$ collisions at $\sqrt{s}$ = 0.9, 2.76 and 7 TeV, in the light of blast-wave model to extract the transverse radial flow velocity and kinetic temperature at freeze-out for the system formed in $pp$ collisions. The dependency of the blast-wave parameters on average charged particle multiplicity of event sample or the `centrality' of collisions has been studied and compared with results of similar analysis in nucleus-nucleus ($AA$) and proton-nucleus ($pA$) collisions. We analyze the spectra of $K_s^0$, $\Lambda$($\bar{\Lambda }$) and ${\Xi }^{-}$ also to see the dependence of blast-wave description on the species of produced particles. Within the framework of the blast-wave model, the study reveals indication of collective behavior for high-multiplicity events in $pp$ collisions at LHC. Strong transverse radial flow in high multiplicity $pp$ collisions and its comparison with that in $pA$ and $AA$ collisions match with predictions from a very recent theoretical work [Shuryak and Zahed 2013 arXiv:1301.4470] that addresses the conditions for applicability of hydrodynamics in $pp$ and $pA$ collisions.

14 pages 8 figures

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Cited by in corpus (17)

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• Femtoscopic signature of strong radial flow in high-multiplicity $pp$ collisions
• Kinetic freeze out conditions in nuclear collisions with $2A$ - $158A$ GeV beam energy within a non-boost-invariant blast-wave model
• Blast-wave model description of the Hanbury-Brown--Twiss radii in pp collisions at LHC energies
• Strange hadron production in pp, pPb and PbPb collisions at LHC energies
• Investigating the soft and hard limits in transverse momentum spectra in pp collisions
• Effect of an anisotropic escape mechanism on elliptic flow in relativistic heavy-ion collisions
• Anomalous features of particle production in high-multiplicity events of pp collisions at the LHC energies
• The effect of single-particle space-momentum angle distribution on two-pion HBT correlation in high-energy heavy-ion collisions
• Multiplicity dependence of charged-particle intra-jet properties in pp collisions at $\sqrt{s}$ = 13 TeV
• Hadron momentum spectra from analytical solutions of relativistic hydrodynamics
• Multiplicity, transverse momentum and pseudorapidity dependence of open-heavy flavored hadron production in proton+proton collisions at $\sqrt{s}$= 13 TeV using PYTHIA8
• Possibility of DCC formation in pp collisions at LHC energy via reaction-diffusion equation
• Energy independent scaling of ridge and final state description of high multiplicity p+p collisions at $\sqrt{s}$ = 7 and 13 TeV