1107.1291 (Premomoy Ghosh)

Analysis of multiplicity distributions in proton-proton collisions at
LHC up to $\sqrt {s}$ = 7 TeV in quantum statistical approach    [PDF]

Premomoy Ghosh

Proton-proton collisions at new high energies ($\sqrt {s}=$2.36 and 7 TeV) at
LHC resulted into a greater mean multiplicities ($$) of charged particles
in the mid-rapidity region than estimated $< n >$s by different models and
event generators. Another significant observation in multiplicity data is a
change in slope in the distribution of primary charged hadrons in
pseudorapidity intervals $|\eta|<2.4$ at $\sqrt{s} = 7$ TeV. These new
observations merit further studies. We consider a two-component model of
particle production to analyze the multiplicity distributions of charged
hadrons from the proton-proton collisions at centre-of-mass energies $\sqrt{s}
= 0.9$ TeV, $\sqrt{s} = 2.36$ TeV and $\sqrt{s} = 7$ TeV in pseudorapidity
intervals $|\eta|$ of increasing width around the centre-of-mass pseudorapidity
$\eta_{cm} =0$. The model, based on quantum statistical formalism, considers
one chaotic and another coherent source of particle productions. The LHC data
has been found to be consistent with characteristic features of the model. The
analysis provides a reasonable explanation to the observed change in slope in
the distribution and suggests a possible reason for underestimations of mean
multiplicities by the event generators. In addition, an interesting revelation
is the deviation from a scaling law, involving information entropy in quantum
statistical viewpoint, derived as a function of chaotic multiplicity obtained
from the two-component model.

View original: http://arxiv.org/abs/1107.1291