On the effect of secondary protons on baryon and proton number cumulants in event-by-event analysis

Abstract

We investigate the effects of secondary (knockout) protons, which constitute about 20% of the observed protons at STAR, on the higher order cumulants of proton and baryon numbers measured by event-by-event analyses in relativistic heavy ion collisions. We argue that the contribution of this background effect on the cumulants is expressed by a simple formula, and that hence their effects can be removed in the experimental analysis. It is discussed that this background effect has non-negligible contribution to recently observed proton number cumulants at STAR, especially the third-order one, and that the removal of this effect is crucial to investigate the thermodynamical properties of the primordial hot medium appropriately.

5 pages, no figures

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Cited by in corpus (6)

• Fluctuations of conserved charges in relativistic heavy ion collisions: An introduction
• Impact of resonance regeneration and decay on the net-proton fluctuations in a hadron resonance gas
• Efficient formulas for efficiency correction of cumulants
• Criticality of the net-baryon number probability distribution at finite density
• Rapidity window dependences of higher order cumulants and diffusion master equation
• A short introduction to heavy-ion physics