Speaker
Grzegorz Andrzej Wilk
(National Centre for Nuclear Research (PL))
Description
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-pT 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-pT 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 pT 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
pT spectra for the whole pT region at central rapidity for pp collisions at high-energies.
Author
Grzegorz Andrzej Wilk
(National Centre for Nuclear Research (PL))
