Collective flow in high-multiplicity proton-proton collisions

Abstract

We present an evidence of strong radial flow in high-multiplicity pp collisions. We analyze the CMS data on the inclusive spectra of the charged pions, kaons and protons in the LHC $\sqrt{s}=7$ TeV collisions. For $<N_{\mathrm{tracks}}>\gtrsim 75$ we demonstrate the consistency of the hydrodynamic description with the (idealized) Gubser's flow. Using a one parameter fit of the model to experimental data, we obtain the initial fireball size to be of the order of 1 fm. At smaller multiplicities, the fit cannot be performed which shows a limitation of the hydrodynamic approach and provides us with falsifiability of our theory.

arXiv comment5 pages

References in corpus (12)

• A Brief Introduction to PYTHIA 8.1
• Collective flow and viscosity in relativistic heavy-ion collisions
• Multiplicity and transverse-momentum dependence of two- and four-particle correlations in pPb and PbPb collisions
• Coalescence and flow in ultra-relativistic heavy ion collisions
• Symmetry constraints on generalizations of Bjorken flow
• Study of the inclusive production of charged pions, kaons, and protons in pp collisions at sqrt(s) = 0.9, 2.76, and 7 TeV
• The "Ridge" in Proton-Proton Scattering at 7 TeV
• High Multiplicity pp and pA Collisions: Hydrodynamics at its Edge
• Elliptic flow in proton-proton collisions at 7 TeV
• Pion femtoscopy in p+p collisions at sqrt(s)=200 GeV
• Indication of transverse radial flow in high-multiplicity proton-proton collisions at the Large Hadron Collider
• Collective interaction of QCD strings and early stages of high multiplicity pA collisions

Cited by in corpus (18)

• Novel Collective Phenomena in High-Energy Proton-Proton and Proton-Nucleus Collisions
• Collectivity without plasma in hadronic collisions
• Experimental overview on small collision systems at the LHC
• Relativistic hydrodynamics in heavy-ion collisions: general aspects and recent developments
• Mass ordering of spectra from fragmentation of saturated gluon states in high multiplicity proton-proton collisions
• Interacting color strings as the origin of the liquid behavior of the quark-gluon plasma
• Hanbury Brown--Twiss Interferometry and Collectivity in Small Systems
• Quasi equilibrium state of expanding quantum fields and two-pion Bose-Einstein correlations in $pp$ collisions at the LHC
• Effect of an anisotropic escape mechanism on elliptic flow in relativistic heavy-ion collisions
• Road map for the tuning of hadronic interaction models with accelerator-based and astroparticle data
• Scaling laws for softened hadron production at LHC energies
• Quantum canonical ensemble and correlation femtoscopy at fixed multiplicities
• Momentum-kick model application to high multiplicity pp collisions at $\sqrt{s}=13\mathrm{TeV}$ at the LHC
• Exploring Strangeness Enhancement and Particle Production in Small Collision Systems with EPOS4 at $\sqrt{s_\rm{NN}}$ = 5.02 TeV
• A combined model for pseudorapidity distributions in Cu-Cu collisions at BNL-RHIC energies
• Azimuthal flow in hadron collisions from quark-gluon string repulsion
• A combined model for the pseudorapidity distributions in p-p collisions at center-of-mass energies from 23.6 to 7000 GeV
• Fixed particle number constraint in a simple model of a thermal expanding system and $pp$ collisions at the LHC