Bayesian model comparison for one-dimensional azimuthal correlations in 200GeV AuAu collisions

Autor: Eggers, Hans C., de Kock, Michiel B., Trainor, Thomas A.
Rok vydání: 2015
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1051/epjconf/201612001006
Popis: In the context of data modeling and comparisons between different fit models, Bayesian analysis calls that model best which has the largest evidence, the prior-weighted integral over model parameters of the likelihood function. Evidence calculations automatically take into account both the usual chi-squared measure and an Occam factor which quantifies the price for adding extra parameters. Applying Bayesian analysis to projections onto azimuth of 2D angular correlations from 200 GeV AuAu collisions, we consider typical model choices including Fourier series and a Gaussian plus combinations of individual cosine components. We find that models including a Gaussian component are consistently preferred over pure Fourier-series parametrizations, sometimes strongly so. For 0-5% central collisions the Gaussian-plus-dipole model performs better than Fourier Series models or any other combination of Gaussian-plus-multipoles.
Comment: 6 pages, 4 figures. Proceedings of the XLV International Symposium on Multiparticle Dynamics, Wildbad Kreuth, 5-9 October 2015
Databáze: arXiv