Double-bottom centrifugal-barrier molecules dancing with four quarks

Abstract

Motivated by the recent Belle II measurement of the open-bottom cross section, we perform a systematic study of the double-bottom molecular tetraquark spectrum, including both $S$-wave and $P$-wave configurations. Using the one-boson-exchange potential and the complex scaling method, we investigate the $B^{(\ast )}{\bar{B}}^{\ast }$ and $B^{(\ast )}{B}^{\ast }$ systems and predict several bound states and resonances. Our analysis reveals a rich spectrum, including $B{\bar{B}}^{\ast }$ ($0(1^{++})$, $0(0^{-+})$), $B^{\ast }{\bar{B}}^{\ast }$ ($0(2^{++})$, $0(0^{-+})$, $0(1^{--})$), $B{B}^{\ast }$ ($0(1^{+})$), and $B^{\ast }{B}^{\ast }$ ($0(1^{+})$) bound states, as well as $B{\bar{B}}^{\ast }$ ($0(1^{--})$, $0(2^{--})$), $B^{\ast }{\bar{B}}^{\ast }$ ($0(3^{--})$), $B{B}^{\ast }$ ($0(0^{-})$), and $B^{\ast }{B}^{\ast }$ ($0(1^{-})$, $0(2^{-})$) resonances. Our results provide theoretical support for the existence of double-bottom tetraquarks and deliver key benchmarks for future searches at LHCb, Belle II, and other experiments.

6 pages, 3 figures