$Ξ$(2030) and $Ξ$(2120) as $\bar{K}^*Σ$ molecular states

Abstract

In this work, the molecular states from the K * Σ interaction are studied in a quasipotential Bethe-Salpeter equation approach with the one-boson-exchange potentials. We consider the exchanges of vector (ρ, ω and φ) mesons and pseudoscalar (π and η) mesons to describe the K * Σ interaction with the coupling constants determined by the SU(3) symmetry, The poles of the scattering amplitude are searched for to find the molecular states dynamically generated from the K * Σ interaction. A bound state with quantum number I(J p ) = 1/2(5/2 + ) is produced, which can be associated to the Ξ(2030) baryon. Other bound states with J ≤ 5/2 are also searched for and it is found that there exist bound states with quantum numbers I(J P ) = 1/2(1/2 − ), 1/2(3/2 − ), and 1/2(3/2 + ). The Ξ(2120) may be a candidate for one of these three bound states. In addition, we also find two bound states with isospin 3/2 and spin parities 1/2 − and 1/2 + .

Hyperon II: Properties of excited hyperons

“…These resonances are called "dynamically generated". Well-known examples in the baryon sector are Λ(1405)1/2 − that is generated from KN − Σπ coupled channel chiral dynamics [1,2,3,4,5,6,7,8,9], N (1535)1/2 − can be interpreted as dynamically generated quasi-bound ΛK − ΣK state [10,11,12], ∆(1700)3/2 − from ∆(1232)η [13], and Ξ(2030) and Ξ(2120) are interpreted as K * Σ molecular states [14]. Further examples can be found in Ref.…”

Analysis of the $η_1(1855)$ as a $K\bar{K}_1(1400)$ molecular state

“…Following the LHCb observation of hidden-charm pentaquark P c (4312, 4440, 4450) [11,12] and their interpretation as Σ ( * ) c D( * ) [13,14] molecules, two nucleon resonances with a mass about 2.0 GeV, the N(1875) and the N(2100), were also interpreted as hadronic molecular states from the Σ * K and ΣK * interactions, respectively [15,16]. Moreover, the interaction between K * and Σ can form a P-wave molecular state that can be associated to the Ξ(2030) [17]. The narrower width of Ξ(1620), Ξ(1690), and Ξ(2120) can be easy understood as molecular state with dominant KΛ − KΣ component [18][19][20].…”