Search for the $\chi _{c1}(3872)\to \chi _{c1}\pi ^{+}\pi ^{-}$ decay in LHCb

Spectroscopy of hadrons with heavy quarks, especially exotic hadrons, is one of the most promising ways to advance understanding of QCD in the non-perturbative regime.
The nature of $χ_{c1}(3872)$ is still under discussion, displaying behaviour of pure charmonium ($c\overline{c}$), compact tetraquark (4 quark) and molecular (2 loosely bound mesons) components.
Measuring the branching fraction of its decay into $\chi _{c1}(1P)\pi ^{+}\pi ^{-}$ will provide further experimental input.