Hidden and doubly heavy molecular states from interactions D ) D s ) / B ) B s ) and D ) D s ) / B ) B s )

In this work, we perform a systematical investigation about the possible hidden and doubly heavy molecular states with open and hidden strangeness from interactions of ) D s ) / ) B s ) , ) D s ) / ) B s ) , ) D s ) / ) B s ) , and D ) D s ) / B ) B s ) in a quasipotential Bethe-Salpeter equation approach. The interactions of the systems considered are described within the one-boson-exchange model, which includes exchanges of light mesons and J / psi / Upsilon meson. Possible molecular states are searched for as poles of scattering amplitudes of the interactions considered. The results suggest that recently observed Z cs ( 3985 ) can be assigned as a molecular state of D D s + D D s , which is a partner of Z c ( 3900 ) state as a D D molecular state. The calculation also favors the existence of hidden heavy states D s D s / B s B s with spin parity J P = 0 + , D s D s / B s B s with 1 + , and D s D s / B s B s with 0 + , 1 + , and 2 + . In the doubly heavy sector, the bound states can be found from the interactions ( D D s + D D s ) / ( B B s + B B s ) with 1 + , D s D s / B s B s with 1 + , D D s ds B B s with 1+ and 2+ , and D s D s with 1 + and 2+ Some other interactions are also found attractive, but may be not strong enough to produce a bound state. The results in this work are helpful for understanding the Z cs ( 3985) and future experimental search for the new molecular states.

Automated summary

In this study, a systematic investigation was conducted on potential hidden and doubly heavy molecular states with open and hidden strangeness using a quasipotential Bethe-Salpeter equation approach. The results suggest that the recently observed Zcs (3985) may be a molecular state, and support the existence of hidden heavy states with different spin parities.