TcS (2900) as a threshold effect from the interaction of the D* K *, D *sρchannels

We look at the mass distribution of the D(S)(+)i Pi(-) In the B-0 ->(DDS+)-D-0 Pi(-)decay, where a peak has been observed in the region of the D (*) (s)rho, D* K* thresholds. By creating these two channels together with a D (0) in B-0 decay and letting them interact as coupled channels, we obtain a structure around their thresholds, short of producing a bound state, which leads to a peak in the D-S(+) Pi(-)mass distribution in the B-0 -> (DDS+)-D-0 Pi(-)decay. We conclude that the interaction between the D*K* and D (*) (s)rho is essential to produce the cusp structure that we associate to the recently seen Tcs(2900), and that its experimental width is mainly due to the decay width of the rho meson. The peak obtained together with a smooth background reproduces fairly well the experimental mass distribution observed in the B (0)-> (DDS+)-D-0 Pi(-) decay.

Automated summary

We study the mass distribution of D(S)(+)i Pi(-) in the B-0 -> (DDS+)-D-0 Pi(-)decay and find a peak near the thresholds of D (*) (s)rho and D* K*. By incorporating the interactions between D*K* and D (*) (s)rho as coupled channels in the B-0 decay, we obtain a structure that leads to a peak in the D-S(+) Pi(-) mass distribution. We conclude that the interaction between D*K* and D (*) (s)rho is essential for the observed cusp structure and that the experimental width is mainly determined by the decay width of the rho meson. The peak, along with a smooth background, reproduces the experimental mass distribution in the B (0)-> (DDS+)-D-0 Pi(-) decay fairly well.