Study of Pc(4457), Pc(4440), and Pc(4312) in a quasipotential Bethe-Salpeter equation approach

Very recently, the LHCb Collaboration reported their new results about the pentaquarks at charm energy region. Based on the newexperimental results, we recalculate the molecular states composed of a S (*) c baryon and a D (*) meson in a quasipotentialBethe- Salpeter equation approach. The two- peak structure around 4450 MeV can be interpreted as two Sc D * bound states with spin parities 1/ 2 - and 3/ 2 -. The newly observed pentaquark Pc( 4312) can be assigned as a Sc D bound state with spin parity 1/ 2 -. The experimental determination of spin parities will be very helpful to understand the internal structure of these pentaquarks.