$$ {\Lambda}_c^{+} $$ polarimetry using the dominant hadronic mode

Abstract

The polarimeter vector field for multibody decays of a spin-half baryon is introduced as a generalisation of the baryon asymmetry parameters. Using a recent amplitude analysis of the $$ {\Lambda}_c^{+} $$ Λ c + → pK−π+ decay performed at the LHCb experiment, we compute the distribution of the kinematic-dependent polarimeter vector for this process in the space of Mandelstam variables to express the polarised decay rate in a model-agnostic form. The obtained representation can facilitate polarisation measurements of the $$ {\Lambda}_c^{+} $$ Λ c + baryon and eases inclusion of the $$ {\Lambda}_c^{+} $$ Λ c + → pK−π+ decay mode in hadronic amplitude analyses.