Related papers: Comment on the X(3915) nonstandard hadron candidat…
We discuss a possible interpretation of the open charm mesons $D_{s0}^*(2317)$, $D_{s1}(2460)$ and the hidden charm mesons X(3872), Y(3940) and Y(4140) as hadron molecules. Using a phenomenological Lagrangian approach we review the strong…
We analyze various possible interpretations of the narrow state $D_{sJ}^+(2632)$ observed by SELEX Collaboration recently, which lies above threshold and has abnormal decay pattern. These interpretations include: (1) several versions of…
The medium modifications of the masses of the charmonium states (J/$\psi$, $\psi$(3686) and $\psi$(3770)) in asymmetric nuclear matter in the presence of strong magnetic fields are studied using an effective chiral model. The mass…
BES Collaboration has recently observed an enhancement near the $\omega\phi$ threshold in the double OZI suppressed decay $J/\psi \to\gamma\omega\phi$. This $\omega\phi$ enhancement is probably due to a new $J^{PC}=0^{++}$ X(1812) state. We…
We report optical and infrared observations of the X-ray source CXOGBS J174623.5-310550. This Galactic object was identified as a potential quiescent low-mass X-ray binary accreting from an M-type donor on the basis of optical spectroscopy…
Nonleptonic $B$ to charmonium decays generally show deviations from the factorization predictions. For example, the mode $B^- \to K^- \chi_{c0}$ has been experimentally observed with sizeable branching fraction while its factorized…
The radio quasar NVSS~J171822+423948 (J1718+4239) was proposed as the counterpart of the IceCube neutrino event IC-201221A. To reveal the nature of the source, we conducted new very long baseline interferometry (VLBI) observations of this…
In this report I review some results on the charmonium and light hadron spectroscopy mainly from BESIII and Belle experiments. For the charmonium, the contents include the observation of $\psi(4040)/\psi(4160) \to \eta \jpsi$, the…
Charmonium is a bound state of a charmed quark and a charmed antiquark, and a charmoniumlike state is a resonant structure that contains a charmed quark and antiquark pair but has properties that are incompatible with a conventional…
The BESIII collaboration has discovered a new state with hidden charm-strange. Its mass is intriguingly close to the $ D_s\bar{D}_{s1} $ threshold and does not have the properties of the charmonium states. Working with the QCD sum rules…
We present X-ray observations of the periodic optical source ZTF J185139.81+171430.3 (hereafter ZTF J1851) by the XMM, NICER and NuSTAR telescopes. The source was initially speculated to be a white dwarf (WD) pulsar system due to its short…
We report the recent evidence for a new narrow structure, Y(4140), decaying to the $J/\psi \phi$ final state, in exclusive $B^+\to J/\psi\phi K^+$ decays in a data sample corresponding to an integrated luminosity of 2.7 \ifb collected at…
Since its first observation in 2005, the vector charmonium $Y(4260)$ has turned out to be one of the prime candidates for an exotic state in the charmonium spectrum. It was recently proposed that the $Y(4260)$ should have a prominent…
The strong decays of $\Xi$ baryons up to N=2 shell were studied in a chiral quark model. The strong decay properties of these well-established ground decuplet baryons were reasonably described. We found that (i) $\Xi(1690)$ and $\Xi(1820)$…
Several states that couple to one light-meson and a heavy-charmonium are recently reported, including the $Z_c(3900)$ and $Z_c(4020)$. These states cannot be interpreted within the constituent quark-model of mesons, and are good candidates…
We systematically investigate the mass spectrum and two-body open-charm strong decays of charmonium states in a coupled-channel model where the $^3P_0$ quark-antiquark pair creation mechanism is employed. The results of masses, mass shifts,…
The newly reported Y(4260) becomes the second most massive state in the charmonium family. We argue that it displaces the psi(4415) as the (largely) 4s vector charmonium state, recall s-d wave interference to explain the lack of a signal in…
We report the observation of the $B$ meson decay $B^\pm\to J/\psi \eta K^\pm$ and evidence for the decay $B^0\to J/\psi \eta K^0_S$, using {90} million $BBbar$ events collected at the $\ensuremath{\Upsilon{(4S)}}\xspace$ resonance with the…
The decays $\chi_{c1} \rightarrow J/\psi \mu^+ \mu^-$ and $\chi_{c2} \rightarrow J/\psi \mu^+ \mu^-$ are observed and used to study the resonance parameters of the $\chi_{c1}$ and $\chi_{c2}$ mesons. The masses of these states are measured…
Discovery of the X(3872) meson in 2003 ignited intense interest in exotic (neither $q\bar{q}$ nor $qqq$) hadrons, but a $c\bar{c}$ interpretation of this state was difficult to exclude. An unequivocal exotic was discovered in the…