Molecular Structure Effects in Low-Lying P-wave Bottom-Strange Meson Spectrum
Abstract
Recently, the LHCb Collaboration reported a new narrow bottom-strange meson, Bs0*(5700) with mass M= (5698.9 ± 1.5 ± 0.6)~MeV, width Γ<9.8~MeV, and spin-parity JP=0+ in the Bs0π0 invariant-mass spectrum. Motivated by this observation, we study the low-lying P-wave Bs mesons in a two-stage refined constituent quark model. The one-loop radiative corrections to the confinement--one-gluon exchange potential (αs2) lower the whole multiplet by $25−−50$~MeV and improve the level ordering; however, the scalar Bs0* mass still exceeds the LHCb data by ∼120~MeV in a purely compact picture. The inclusion of the coupled-channel dynamics is decisive: the BK threshold, lying close to the scalar mass, generates a sizeable meson--meson (molecular-like) component that pulls the pole down to ∼5727~MeV, within $30$~MeV of the measurement, and simultaneously suppresses the S-wave phase space, naturally accounting for the anomalously narrow width. Consistent results are obtained for the 1+ Bs1 partner, for which we predict a mass ∼5747--$5755$~MeV, in agreement with the chiral-doubling scenario. The Bs1 state is expected to be very narrow and decaying mainly through the isospin-violating Bs*π0 and radiative Bsγ, Bs*γ modes, providing a clear discovery target at LHC Run~3. The E1 radiative widths of the jℓ=1/2 states are predicted at the 50∼ 60~keV, and the strong width of the pure jℓ=3/2 state Bs2*(5840) ($1.5$~MeV) reproduces the measurement. Our results support the interpretation of Bs0*(5700) as a near-threshold scalar with strong molecular dressing and establish the predicted 1+ Bs1(5747) as the decisive test of the hadronic dynamics in the Bs sector.
Related
- Exploring the P-wave bottom-strange molecular pentaquarks with the complex scaling method
- The new LHCb beauty-strange state as the bottom partner of the Ds0*(2317): a LQCD constrained coupled-channel chiral analysis
- Properties of the positive and negative parity charm-strange and bottom-strange mesons Ds, Ds*, Ds0*, Ds1, Bs, Bs*, Bs0*, Bs1 from lattice QCD: masses, decay constants, and compositeness
- Electromagnetic structure of strange vector mesons in nuclear medium
- Electromagnetic structure of charged and neutral strange vector mesons
BibTeX
@misc{hao2026molecular,
title = {{Molecular Structure Effects in Low-Lying $P$-wave Bottom-Strange Meson Spectrum}},
author = {Wei Hao and Guan-Ying Wang and M. Atif Sultan and En Wang},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.07106},
eprint = {2610.07106},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.07106},
}
RIS
TY - UNPB
TI - Molecular Structure Effects in Low-Lying P-wave Bottom-Strange Meson Spectrum
AU - Wei Hao
AU - Guan-Ying Wang
AU - M. Atif Sultan
AU - En Wang
PY - 2026
DA - 2026/10/05
PB - arXiv
DO - 10.48550/arxiv.2610.07106
UR - https://arxiv.org/abs/2610.07106
AB - Recently, the LHCb Collaboration reported a new narrow bottom-strange meson, B_s0^*(5700) with mass M= (5698.9 ± 1.5 ± 0.6)~MeV, width Γ<9.8~MeV, and spin-parity J^P=0^+ in the B_s^0π^0 invariant-mass spectrum. Motivated by this observation, we study the low-lying P-wave B_s mesons in a two-stage refined constituent quark model. The one-loop radiative corrections to the confinement--one-gluon exchange potential (α_s^2) lower the whole multiplet by $25−−50$~MeV and improve the level ordering; however, the scalar B_s0^* mass still exceeds the LHCb data by ∼120~MeV in a purely compact picture. The inclusion of the coupled-channel dynamics is decisive: the BK threshold, lying close to the scalar mass, generates a sizeable meson--meson (molecular-like) component that pulls the pole down to ∼5727~MeV, within $30$~MeV of the measurement, and simultaneously suppresses the S-wave phase space, naturally accounting for the anomalously narrow width. Consistent results are obtained for the 1^+ B_s1 partner, for which we predict a mass ∼5747--$5755$~MeV, in agreement with the chiral-doubling scenario. The B_s1 state is expected to be very narrow and decaying mainly through the isospin-violating B_s^*π^0 and radiative B_sγ, B_s^*γ modes, providing a clear discovery target at LHC Run~3. The E1 radiative widths of the j_ℓ=1/2 states are predicted at the 50∼ 60~keV, and the strong width of the pure j_ℓ=3/2 state B_s2^*(5840) ($1.5$~MeV) reproduces the measurement. Our results support the interpretation of B_s0^*(5700) as a near-threshold scalar with strong molecular dressing and establish the predicted 1^+ B_s1(5747) as the decisive test of the hadronic dynamics in the B_s sector.
ER -