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arXiv · 2001.06533

Study of excited $Λ_\mathrm{b}^0$ states decaying to $Λ_\mathrm{b}^0π^+π^-$ in proton-proton collisions at $\sqrt{s} =$ 13 TeV

CMS Collaboration
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Abstract

A study of excited $Λ_\mathrm{b}^0$ baryons is reported, based on a data sample collected in 2016-2018 with the CMS detector at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of up to 140 fb$^{-1}$. The existence of four excited $Λ_\mathrm{b}^0$ states: $Λ_\mathrm{b}$(5912)$^0$, $Λ_\mathrm{b}$(5920)$^0$, $Λ_\mathrm{b}$(6146)$^0$, and $Λ_\mathrm{b}$(6152)$^0$ in the $Λ_\mathrm{b}^0π^+π^-$ mass spectrum is confirmed, and their masses are measured. The $Λ_\mathrm{b}^0π^+π^-$ mass distribution exhibits a broad excess of events in the region of 6040-6100 MeV, whose origin cannot be discerned with the present data.

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CMS Collaboration. 2020-03-14. Study of excited $Λ_\mathrm{b}^0$ states decaying to $Λ_\mathrm{b}^0π^+π^-$ in proton-proton collisions at $\sqrt{s} =$ 13 TeV. https://doi.org/10.1016/j.physletb.2020.135345

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