A Monte-Carlo generator for statistical hadronization in high energy e+e− collisions

Abstract

We present a Monte-Carlo implementation of the Statistical Hadronization Model in e + e − collisions. The physical scheme is based on the statistical hadronization of massive clusters produced by the event generator Herwig within the microcanonical ensemble. We present a preliminary comparison of several observables with measurements in e + e − collisions at the Z peak. Although a fine tuning of the model parameters is not carried out, a general good agreement between its predictions and data is found.

Jet mass dependence of fragmentation in positron-proton collisions

“…Microcanonical statistics has been widely used in the literature in the description of hadronisation [14,[16][17][18][19][20][21][22][23][24][25]. Using the microcanonical instead of the canonical ensemble is important, as the energy of a single hadron in a jet can easily be of the order of the total energy of the jet.…”

“…The advantage of the model presented here is that (after neglecting hadron masses, and using a relativistic ensemble,) we are able to derive simple analytic expressions, while the usage of a non-relativistic ensemble leads to rather complicated results [23]. The disadvantage of neglecting hadron masses is that ratios of total particle multiplicities cannot be reproduced as has been done in more complicated simulations [19][20][21][22] taking masses into account.…”

“…Thus, the QCD result for the scale dependence of the parameters can be obtained by replacing the (t/t 0 ) a1,2 terms in Eq. (19) by the corresponding more complicated functions.…”

Three-dimensional Statistical Jet Fragmentation

“…Besides, there are many attempts to obtain fragmentation functions from model calculations. Among all, here, we refere to statistical physical models [5]- [8] which take into account the finiteness of the energy of the created hadronic system, thus, being suitable for the description of momentum fraction and multiplicity distributions of hadrons stemming from jets in e + e − and pp collisions. In [6,7], analitic expressions (cut-power law functions) are obtained for hadron momentum fraction distributions using microcanonical ensemble and superimposed Euler-gamma-type multiplicity fluctuations.…”

Multiplicity Dependence of Hadron Spectra in Proton-proton Collisions at LHC Energies and Super-statistics

“…These models are based on the conjecture that in high-energy collisions, small thermal droplets of matter (often refered to as "fireballs" or "clusters") are created and these droplets fragment into hadrons. The calculations are carried through either in the canonical [13,14,37,38,42,43] or microcanonical [4,16,17,34,35,36,41] framework, and describe measured data on hadron specra, total hadron multiplicities as well as multiplicity distributions. The latter can be approximated by either the negative binomial or by Euler's gamma-distribution.…”