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arXiv · 1910.14066

The factorization bias in the Van der Meer method: Run 2 experiences at the CMS experiment

Joscha Knolle
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Abstract

The luminosity measurement of the CMS experiment at the CERN LHC is calibrated with Van der Meer (VdM) scans. A bias occurs in the VdM method due to the assumption of transversely factorizable proton densities of the LHC beams. Here, the different methods applied in Run 2 to estimate the size of the factorization bias are reported. The beam-imaging method reconstructs the transverse proton densities from beam-imaging scans. Additional methods exploit offset scans, analyze the evolution of the measured luminous region, and evaluate diagonal scans.

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Joscha Knolle. 2019-10-30. The factorization bias in the Van der Meer method: Run 2 experiences at the CMS experiment. https://arxiv.org/abs/1910.14066

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