The LHCb state PψsΛ(4338) as a triangle singularity

Hidden-Charm Pentaquarks with Strangeness in a Chiral Quark Model

“…The spin-parity values of these two exotic states, P cs (4338) and P cs (4459), are preferably 1 2 − and 3 2 − , respectively. These facts have triggered an enormous amount of theoretical investigations; concerning the hidden-charm pentaquark candidates with strangeness, one may mention, for instance, the works performed within effective field theories [5][6][7][8][9][10], using QCD sum rules [11][12][13][14][15] or based on phenomenological quark models [16][17][18][19][20][21][22][23], generally establishing that the P cs (4338) state can be identified as a Ξ c D( * ) molecular structure whereas the P cs (4459) state seems better for being a Ξ compact structure analysis [26,27] and triangle singularities [28] could also explain the nature of the mentioned P cs states. In addition, several additional exotic states in the hidden-charm pentaquark sector with strange quark content are theoretically proposed in Refs.…”

Hidden-charm tetraquarks with strangeness in the chiral quark model

“…These facts have triggered an enormous amount of theoretical investigations; concerning the hidden-charm pentaquark candidates with strangeness one may mention, for instance, the works done within effective field theories [5][6][7][8][9][10], using QCD sum rules [11][12][13][14][15] or based on phenomenological quark models [16][17][18][19][20][21][22][23], generally stablishing that the P cs (4338) state can be identified as a Ξ c D( * ) molecular structure whereas the P cs (4459) seems better to be a Ξ ( ′ , * ) c D( * ) hadronic molecule. However, mixed configurations [24,25], compact structure analysis [26,27] and triangle singularities [28] could also explain the nature of the mentioned P cs states. In addition, several additional exotic states in the hidden-charm pentaquark sector with strange quark content are theoretically proposed in Refs.…”