Masses of tetraquarks with open charm and bottom

The masses of the heavy tetraquarks with open charm and bottom are calculated within the diquark-antidiquark picture in the framework of the relativistic quark model. The dynamics of the light quarks and diquarks is treated completely relativistically. The diquark structure is taken into account by calculating the diquark-gluon form factor. New experimental data on charmed and charmed-strange mesons are discussed. Our results indicate that the anomalous scalar D_{s0}^*(2317) and axial vector D_{s1}(2460) mesons could not be considered as diquark-antidiquark bound states. On the other hand, D_s(2632) and D_{sJ}^*(2860) could be interpreted as scalar and tensor tetraquarks, respectively. The predictions for masses of the corresponding bottom counterparts of the charmed tetraquarks are given.