- Bunching parameter
In
statistics as applied in particular inparticle physics , whenfluctuation s of someobservable s are measured,it is convenient to transform themultiplicity distribution to the bunching parameters::eta_q =frac{q}{q-1}frac{P_q P_{q-2{P_{q-1}^2},where P_n is probability of observingn objects inside of somephase space regions.The bunching parameters measure deviations ofthe multiplicity distribution P_nfrom aPoisson distribution , sincefor this distribution:eta_q=1.
Uncorrelated particle production leadsto the Poisson statistics, thusdeviations of the bunching parameters from the Poisson valuesmean correlations between particles and dynamical fluctuations.Normalised factorial moment shave also similar properties.They are defined as:F_q =langle n angle^{-q}sum^{infty}_{n=q} frac{n!}{(n-q)!} P_n.
ee also
References
* [http://arxiv.org/abs/hep-ph/9605379] Bunching Parameter and Intermittency in High-Energy Collisions;Authors: S.V.Chekanov and V.I.Kuvshinov;Ref: Acta Phys. Pol. B25 (1994) p.1189-1197
* [http://arxiv.org/abs/hep-ph/9606202] Multifractal Multiplicity Distribution in Bunching-Parameter Analysis; Authors: S.V.Chekanov and V.I.Kuvshinov;Ref: J. Phys G22 (1996), p.601-610
* [http://arxiv.org/abs/hep-ph/9606335] Generalized Bunching Parameters and Multiplicity Fluctuations in Restricted Phase-Space Bins;Authors: S.V.Chekanov, W.Kittel and V.I.Kuvshinov; Ref: Z. Phys. C74 (1997) p.517-529External links
Wikimedia Foundation. 2010.