Search for b hadron decays to long-lived particles in the CMS endcap muon detectors

CMS Collaboration

doi:10.1103/7ldn-snzn

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arXiv · 2508.06363

Search for b hadron decays to long-lived particles in the CMS endcap muon detectors

CMS Collaboration

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Abstract

A search for long-lived particles originating from the decay of b hadrons produced in proton-proton collisions with a center-of-mass energy of 13 TeV at the LHC is presented. The analysis is performed on a data set recorded in 2018, corresponding to an integrated luminosity of 41.6 fb$^{-1}$. Interactions of the long-lived particles in the CMS endcap muon system would create hadronic or electromagnetic showers, producing clusters of detector hits. Selected events contain at least one such high-multiplicity cluster in the muon endcaps and require the presence of a displaced muon. The most stringent upper limits to date on the branching fraction $\mathcal{B}$(B $\to$ K$\Phi$), where the long-lived particle $\Phi$ decays to a pair of hadrons, are obtained for $\Phi$ masses of 0.3$-$3.0 GeV and $\Phi$ mean proper decay lengths in the range of 1$-$500 cm.

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CMS Collaboration. 2025-08-08. Search for b hadron decays to long-lived particles in the CMS endcap muon detectors. https://doi.org/10.1103/7ldn-snzn

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