Statistical Power-Law Spectra due to Reservoir Fluctuations

Abstract

LHC ALICE data are interpreted in terms of statistical power-law tailed pT spectra. As explanation we derive such statistical distributions for particular particle number fluctuation patterns in a finite heat bath exactly, and for general thermodynamical systems in the subleading canonical expansion approximately. Our general result, $q=1-1/C+\Delta T^2/T^2$, demonstrates how the heat capacity and the temperature fluctuation effects compete, and cancel only in the standard Gaussian approximation.

Comments: Latex 4 pages, 2 figs, PRL style