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arXiv · 1901.03265

Event activity measurements and mid-rapidity correlations in 200 GeV p+Au collisions at STAR

David Stewart
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Abstract

These proceedings report preliminary measurements of correlations between mid-rapidity charged tracks and high-rapidity event activity (EA) at STAR for $\sqrt{s_\mathrm{NN}}= 200\, \mathrm{GeV}$ p+Au collisions taken in 2015. These correlations are intriguing because they inform the current debate over use of the Glauber model in `small' systems (here meaning p+A or d+A and denoted as `s+A') and have implications for calculating nuclear modification and quenching observables in these systems. The results support concerns about centrality binning in p+Au collisions, and as such motivate using ratios of semi-inclusive, as opposed to fully inclusive, jet spectra to look for jet enhancement or suppression.

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David Stewart. 2019-01-10. Event activity measurements and mid-rapidity correlations in 200 GeV p+Au collisions at STAR. https://doi.org/10.3390/proceedings2019010049

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