Possible Implication of a Single Nonextensive p_T Distribution for Hadron Production in High-Energy pp Collisions^⋆

¹ Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
² National Centre for Nuclear Research, Warsaw 00-681, Poland
³ Centro Brasileiro de Pesquisas Fisicas & National Institute of Science and Technology for Complex Systems, Rua Xavier Sigaud 150, 22290-180 Rio de Janeiro - RJ, Brazil
⁴ Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA

^a e-mail: wongc@ornl.gov
^b e-mail: wilk@fuw.edu.pl
^c e-mail: cirto@cbpf.br
^d e-mail: tsallis@cbpf.br

Published online: 24 March 2015

Abstract

Multiparticle production processes in pp collisions at the central rapidity region are usually considered to be divided into independent “soft” and “hard” components. The first is described by exponential (thermal-like) transverse momentum spectra in the low-p_T region with a scale parameter T associated with the temperature of the hadronizing system. The second is governed by a power-like distributions of transverse momenta with power index n at high-p_T associated with the hard scattering between partons. We show that the hard-scattering integral can be approximated as a nonextensive distribution of a quasi-power-law containing a scale parameter T and a power index n = 1/(q−1), where q is the nonextensivity parameter. We demonstrate that the whole region of transverse momenta presently measurable at LHC experiments at central rapidity (in which the observed cross sections varies by 14 orders of magnitude down to the low p_T region) can be adequately described by a single nonextensive distribution. These results suggest the dominance of the hard-scattering hadron-production process and the approximate validity of a “no-hair” statistical-mechanical description of the p_T spectra for the whole p_T region at central rapidity for pp collisions at high-energies.