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arXiv · 1607.00786

Exclusive Photoproduction of Upsilon in pPb collisions with the CMS

Ruchi Chudasama·Dipanwita Dutta
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Abstract

Results of exclusive photoproduction of Upsilon states in Ultraperipheral collisions (UPC) of protons and ions with the CMS experiment are presented, which provides a clean probe of the gluon distribution at small values of parton fractional momenta $x \approx 10^{-2} 10^{4}$ at central rapidities (|y| $< 2.5$). The three Upsilon states (1S, 2S, 3S) are measured in the dimuon decay channel along with the photon-photon decaying to dimuon QED continuum at $\sqrt{s_{NN}}=5.02$~TeV for integrated luminosity of $L_{int} = 35$ nb$^{-1}$. The total Upsilon photoproduction cross sections at different photon-proton center of mass energy $W_{\gamma p}$ and t-differential distributions are presented and compared with other experimental results as well as theoretical predictions.

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Ruchi Chudasama, Dipanwita Dutta. 2016-07-04. Exclusive Photoproduction of Upsilon in pPb collisions with the CMS. https://arxiv.org/abs/1607.00786

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