Evidence for a new structure in the $J/\psi p$ and $J/\psi \bar{p}$ systems in $B_s^0 \to J/\psi p \bar{p}$ decays

TL;DR

This paper reports the discovery of a new structure in the $J/ar{p}$ systems observed in $B_s^0$ decays, providing evidence for potential exotic states with a significance of up to 3.7 sigma.

Contribution

It presents the first amplitude analysis of $B_s^0 o J/ar{p} p$ decays, revealing a new resonance structure in the $J/ar{p}$ systems.

Findings

Evidence for a new structure at 4337 MeV in $J/ar{p}$ systems.

Measured width of the new structure is approximately 29 MeV.

Significance of the structure ranges from 3.1 to 3.7 sigma.

Abstract

An amplitude analysis of flavour-untagged $B_s^0 \to J/\psi p \bar{p}$ decays is performed using a sample of $797\pm31$ decays reconstructed with the LHCb detector. The data, collected in proton-proton collisions between 2011 and 2018, correspond to an integrated luminosity of 9 $\text{fb}^{-1}$. Evidence for a new structure in the $J/\psi p$ and $J/\psi \bar{p}$ systems with a mass of $4337 \ ^{+7}_{-4} \ ^{+2}_{-2}~\text{MeV}$ and a width of $29 \ ^{+26}_{-12} \ ^{+14}_{-14}~\text{MeV}$ is found, where the first uncertainty is statistical and the second systematic, with a significance in the range of 3.1 to 3.7 $\sigma$, depending on the assigned $J^P$ hypothesis.