Decay processes of a pseudoscalar $D(2900)$

Abstract: We study the decay properties of a $D(2900)$ state, with spin-parity $0^-$, whose existence was proposed in an earlier study of the $D K\bar K$ and coupled channel system. It was found in the former work that a $D$-meson appears with a mass of about 2900 MeV from the three-body dynamics while the charmless subsystem of the pseudoscalar mesons forms the $f_0(980)$ resonance. Motivated by the recent experimental investigations of $D$-mesons around 3000 MeV, we now study the two-body decays of $D(2900)$. We find that the nature of the said state sets the main decay channels to be $D^*\pi$, $D^{*}_s \bar K$ and $D^*_{s0}(2317)\bar K$. It turns out that decay width to the last one is the largest, making the $D^*_{s0}(2317)\bar K$ system to be the most favorable one to look for a signal of $D(2900)$. We compare the decay properties of our state with those of the $D$-meson states, proposed within quark models, near 3000 MeV. We hope that our findings and discussions can be useful for the future experimental investigations of charm mesons around 3000 MeV.