1202.4221 (Premomoy Ghosh)

Negative binomial multiplicity distribution in proton-proton collisions
in limited pseudorapidity intervals at LHC up to sqrt (s) = 7 TeV and the
clan model    [PDF]

Premomoy Ghosh

Experiments at the Large Hadron Collider (LHC) have measured multiplicity
distributions in proton-proton collisions at a new domain of center-of-mass
energy ($\sqrt {s}$) in limited pseudorapidity intervals. We analyze
multiplicity distribution data of proton-proton collisions at LHC energies as
measured by the Compact Muon Solenoid (CMS) experiment in terms of
characteristic parameters of the Negative Binomial Distribution (NBD) function
that has played a significant role in describing multiplicity distribution data
of particle production in high energy physics experiments, in the pre-LHC
energy-range, in various kinds of collisions for a wide range of collision
energy and for different kinematic ranges. Beside a single NBD, we apply the
formalism of weighted superposition of two NBDs to examine if the multiplicity
distribution data of CMS could be better explained. The weighted superposition
of two NBDs indeed explain the distribution data better at the highest
available LHC energy and in large interval of phase space. The two-NBD
formalism further reveals that the energy invariance of the multiplicity
distribution of the "soft" component of particle production in hadronic
collisions is valid at LHC also, as it is at RHIC and Tevatron. We analyze the
data further in terms of clan parameters in the framework of the two-NBD model.

View original: http://arxiv.org/abs/1202.4221