Initial energy density of $\sqrt{s}=$ 7 and 8 TeV p+p collisions at the LHC

Abstract

Results from the RHIC and LHC experiments show, that in relativistic heavy ion collisions, a new state of matter, a strongly interacting perfect fluid is created. Accelerating, exact and explicit solutions of relativistic hydrodynamics allow for a simple and natural description of this medium. A finite rapidity distribution arises from these solutions, leading to an advanced estimate of the initial energy density of high energy collisions. These solutions can be utilized to describe various aspects of proton-proton collisions, as originally suggested by Landau. We show that an advanced estimate based on hydrodynamics yields an initial energy density in $\sqrt{s}=7$ and 8 TeV p+p collisions at LHC on the same order as the critical energy density from lattice QCD, and a corresponding initial temperature around the critical temperature from QCD and the Hagedorn temperature. The multiplicity dependence of the estimated initial energy density suggests that in high multiplicity pp collisions at the LHC, there is large enough initial energy density to create a non-hadronic perfect fluid.

18 pages, 4 figures. Accepted for publication in the Special Issue "Quark-Gluon Plasma in the Early Universe and in Ultra-Relativistic Heavy-Ion Collisions" of Universe (ISSN 2218-1997)

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Cited by in corpus (4)

• Dynamical analysis of cosmological models with non-Abelian gauge vector fields
• Jet quenching from heavy to light ion collisions
• Analysis of multiplicity dependencies of midrapidity pt distributions of identified charged particles in p+p collisions at (s)1/2=7 TeV at the LHC
• Charged particle pseudorapidity distributions measured with the STAR EPD