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arXiv · 1303.3338

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

Hirosato Ono·Masayuki Asakawa·Masakiyo Kitazawa
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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.

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Hirosato Ono, Masayuki Asakawa, Masakiyo Kitazawa. 2013-03-14. On the effect of secondary protons on baryon and proton number cumulants in event-by-event analysis. https://doi.org/10.1103/physrevc.87.041901

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