A triangle singularity and the LHCb pentaquarks

TL;DR

This paper proposes that triangle singularities, a specific reaction mechanism, can explain the observed pentaquark signals at LHCb without requiring new particles.

Contribution

It introduces the triangle singularity as a plausible alternative explanation for the LHCb pentaquark signals, challenging the interpretation of these peaks as genuine resonances.

Findings

Triangle singularity can produce peaks similar to pentaquark signals.

The observed phase motion supports the triangle singularity mechanism.

Kinematic conditions at LHCb favor the formation of such singularities.

Abstract

In this article, a possible interpretation of the pentaquark candidates recently observed at LHCb is given. We show that the reaction dynamics and the peculare kinematics situation can produce the peak in the spectrum and the sharp phase motion. The mechanism called triangle singularity likely causes the appearance of the new pentaquarks candidates.