On the possible virtual state nature of the LHCb Pc (4312)+ signal

J A Silva-Castro

doi:10.1088/1742-6596/1610/1/012015

Abstract

In this contribution we study the nature of the new Pc (4312)+ signal reported by LHCb collaboration in the J/ψ p spectrum. We use S-matrix principles to perform a minimum-bias analysis of the data, focusing on the analytic properties that can be related to the microscopic origin of the Pc (4312)+ peak. Using the scattering length approximation we find evidence for interpretation of the signal as a virtual state generated by the attractive effect of the channel opening.

Highlights

Searching for and understanding of exotic hadron states, say, those that go beyond the minimal quark model combination of three quarks for baryons and a quark-antiquark pair for mesons, has become a relevant topic in physics over the recent years, because of the insight that these states can provide on the strong interaction in the hadronic energy regime [1, 2, 3]
These states are allowed within Quantum Chromodynamics (QCD), as the fundamental theory of the strong interaction only requires that hadrons are color singlets without limiting the number of quarks
It turns out that there are four Riemann sheets, and in the scattering length approximation any pole can only appear on either the II or the IV sheets [21]. This parameterization allows for the description of bound molecules and unbound virtual states

Summary

Introduction

Searching for and understanding of exotic hadron states, say, those that go beyond the minimal quark model combination of three quarks for baryons and a quark-antiquark pair for mesons, has become a relevant topic in physics over the recent years, because of the insight that these states can provide on the strong interaction in the hadronic energy regime [1, 2, 3]. 2. Analysis of the Pc(4312)+ region A thoroughgoing analysis of the Pc(4312)+ signal, for example, to determine its quantum numbers would require a full six-dimensional amplitude analysis fitting both the energy and angular dependencies. Thereby, we consider a coupled channel amplitude between the J/ψ p and Σ+c D 0 channels and restrict the analysis to the 4250-4380 MeV region where the Pc(4312)+ signal is found.

Results

Conclusion