$\gamma\gamma$ and $\gamma p$ measurements with forward proton taggers in CMS+TOTEM

J. Hollar

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arXiv · 1709.02985

$\gamma\gamma$ and $\gamma p$ measurements with forward proton taggers in CMS+TOTEM

J. Hollar

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Abstract

The CMS+TOTEM Precision Proton Spectrometer operated for the first time in 2016, collecting data during $pp$ collisions at $\sqrt{s} = 13$ TeV at the CERN Large Hadron Collider. Procedures for the detector alignment, optics corrections, and background estimations were developed, and applied to an analysis of the process $pp \rightarrow p \mu^{+}\mu^{-} p^{(*)}$ with dimuon masses larger than 110 GeV. A total of 12 candidate events are observed, corresponding to an excess of $>4\sigma$ over the background prediction. This constitutes the first evidence for this process at such masses, and demonstrates the good performance of CT-PPS.

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J. Hollar. 2017-09-09. $\gamma\gamma$ and $\gamma p$ measurements with forward proton taggers in CMS+TOTEM. https://arxiv.org/abs/1709.02985

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