We study the production of the spin partner of the X(3872), which is a D^{ *}\bar D^{ *} bound state with quantum numbers J^{ PC}=2^{ ++} and named X_2(4012) here, with the associated emission of a photon in electron--positron collisions. The results show that the ideal energy region to observe the X_2(4012) in e^+e^- annihilations is from 4.4~GeV to 4.5~GeV, due to the presence of the S-wave \bar D^{ *} D_1(2420) and \bar D^{ *} D_2(2460) thresholds, respectively. We also point out that it will be difficult to observe the \gamma X(4012) at the e^+e^- center-of-mass energy around 4.26~GeV.
Categories: hep-ph hep-ex