Conveners
Session 2
- Zhiqing Liu (Shandong University)
We will present recent analyses on how lineshape studies can shed light on the nature of several exotic candidates
If the $X(3872)$ or $T_{cc}^+(3875)$ is a weakly bound charm-meson molecule, it can be produced by the creation of $D^\ast \bar D^\ast$ or $D^\ast D^\ast$ at short distances followed by the rescattering of the charm mesons into $X(3872)$ or $T_{cc}^+(3875)$ and a pion or a photon through a triangle loop. A triangle singularity produces narrow peak in the reaction rate in production of...
Recently, many new hadronic states were found that do not fit into the simple constituent-quark model for mesons and baryons. One prominent example is the $a_1(1420)$ signal that was observed by the COMPASS experiment in the $f_0(980)\pi$ $P$-wave with $J^{PC}=1^{++}$ quantum numbers.
Different mechanisms were suggested to explain these signals, one of which is rescattering of...
We present the first lattice QCD calculation of partial decay width from $J/\psi$ to $\gamma\eta$ to confirm that QCD $U_A(1)$ anomaly enhances the coupling of gluons with flavor singlet pseudoscalar mesons. The lattice simulation is carried out using $N_f=2$ lattice QCD gauge configurations at the pion mass $m_{\pi} \approx 350$ MeV. In particular, the distillation method has been utilized to...
