The Tsallis distribution in proton-proton collisions at [square root of s]= 0.9 TeV at the LHC

Abstract

The Tsallis distribution has been used recently to fit the transverse momentum distributions of identified particles by the STAR (Abelev et al (STAR Collaboration) 2007 Phys. Rev. C 75 064901) and PHENIX (Adare et al (PHENIX Collaboration) 2011 Phys. Rev. C 83 064903) collaborations at the Relativistic Heavy Ion Collider and by the ALICE (Aamodt et al (ALICE Collaboration) 2011 Eur. Phys. J. C 71 1655) and CMS (Khachatryan et al (CMS Collaboration) 2011 J. High Energy Phys. JHEP05(2011)064) collaborations at the Large Hadron Collider. Theoretical issues are clarified concerning the thermodynamic consistency of the Tsallis distribution in the particular case of relativistic high-energy quantum distributions. An improved form is proposed for describing the transverse momentum distribution and fits are presented together with estimates of the parameter q and the temperature T.