2019-05-16

Report by He Liping

Title: Production of X(3872) and a Photon or a Pion

Time: 9:30 a.m. Monday June 3, 2019

Location: Conference Room 3016 Gezhi Building

The discovery of dozens of unexpected exotic hadrons containing a heavy quark and its antiquark presents a major challenge to our understanding of QCD. A consensus has not even been reached on the nature of the first one to be discovered: the X(3872). The observation in its decay modes has not been effective in discriminating between different models. There may be aspects of the production of X(3872) that are more effective at discriminating between models than the decays of X(3872).

If the X(3872) is a weakly bound charm-meson molecule, it can be produced by the creation of $D^{*0} \bar{D}^0$ or $D^0\bar{D}^{0)$ at short distances followed by the formation of the bound state from the charm-meson pairs. It can also be produced by the creation of $D^ \bar D^$ at short distances followed by the rescattering of the charm mesons into X(3872) and a photon or X(3872) and a pion. In this talk, I would talk about the production of X(3872) and a photon in electron positron collisions and the production of X(3872) and a pion from B meson decay and at hadron colliders, based on X(3872) as a loosely bound charm-meson molecule.