相关论文: Studying the Pc(4450) resonance in J/psi photoprod…
A resonance-like structure, the P_c(4450), has recently been observed in the J/psi p spectrum by the LHCb collaboration. We discuss the feasibility of detecting this structure in J/psi photoproduction in the CLAS12 experiment at JLab. We…
We present results and suggestions on how to confirm the existence and resonant nature of the $Pc(4450)$ detected at LHCb through photoproduction experiments. We find that this narrow structure might have escaped detection in past…
Inspired by the observation of the pentaquark states $P_{c}(4312),P_{c}(4440)$ and $P_{c}(4457)$ at LHCb, photoproduction of these three $P_{c}$ states via the interaction $\gamma p\rightarrow J/\psi p$ is investigated in an effective…
We study the near-threshold $J/\psi$ meson photoproduction from protons and nuclei by considering incoherent direct non-resonant (${\gamma}p \to {J/\psi}p$, ${\gamma}n \to {J/\psi}n$) and two-step resonant (${\gamma}p \to P_{ci}^+ \to…
The LHCb Collaboration announced two pentaquark-like structures in the $J/\psi p$ invariant mass distribution. We show that the current information on the narrow structure at 4.45 GeV is compatible with kinematical effects of the…
We study the $J/\psi$ photoproduction from nuclei at near-threshold incident photon energies of 5--11 GeV within the nuclear spectral function approach by considering incoherent direct (${\gamma}N \to {J/\psi}N$) and two-step (${\gamma}p…
Very recently, the LHCb collaboration released the newest measurements of $B_s \to J/\psi p\bar{p}$, where an enhancement structure near 4.34 GeV was observed in the invariant mass spectrum of $J/\psi p$ with the statistical significance of…
We develop a model for the production of the Pc states observed at LHCb in Lambdab - Jpsi p K- decays. With fewer parameters than other approaches, we obtain excellent fits to the Jpsi-p invariant mass spectrum, capturing both the prominent…
We point out that the new exotic resonances recently reported by LHCb in the $J/\psi p$ channel are excellent candidates for photoproduction off a proton target. This test is crucial to confirming the resonant nature of such states, as…
It was proposed that the narrow $P_c(4450)$ structure observed by the LHCb Collaboration in the reaction $\Lambda_b\to J/\psi p K$ might be due to a triangle singularity around the $\chi_{c1}$--proton threshold at 4.45~GeV. We discuss the…
We study the $J/\psi$ photoproduction from nuclei in the near-threshold beam energy region of $E_{\gamma}$=5--11 GeV within the nuclear spectral function approach by considering incoherent direct (${\gamma}N \to {J/\psi}N$) and two-step…
A reaction model for $\gamma + p \to J/\psi + p$ photoproduction, which exposes the $c \bar c$ content of the photon in making the transition $\gamma\to c\bar c + \mathbb P \to J/\psi$ and couples the intermediate $c \bar c$ system to the…
The newly measurement of production fractions of $P_c$ states by LHCb collaboration have put restriction on their branching ratios of $J/\psi p$ decay, thus constraining their photoproduction in $\gamma p\to J/\psi p$ reaction. We show the…
The LHCb Collaboration has recently observed four $J/\psi\phi$ structures called $X(4140)$, $X(4274)$, $X(4500)$ and $X(4700)$ in the $B^{+}\to J/\psi\phi K^{+}$ decays. We study them herein using a nonrelativistic constituent quark model…
We present a measurement of the inelastic, non diffractive J/$\psi$ photoproduction cross section in the reaction $e^{+} p \to e^{+} {J}/\psi X$ with the ZEUS detector at HERA. The J/$\psi$ was identified using both the $\mu^{+}\mu^{-}$ and…
We study the near-threshold $J/\psi$ meson production on protons and nuclei by considering incoherent direct non-resonant $K^-p \to {J/\psi}\Lambda$ and two-step resonant ${K^-}p \to P_{cs}(4459)^0 \to {J/\psi}\Lambda$ charmonium production…
Ultra-peripheral collisions of heavy ions provide a unique environment to study the gluon structure of nuclei through photon-induced reactions. In particular, the incoherent photoproduction of J/$\psi$ vector meson is sensitive to…
The ALICE collaboration has made the first measurement at the LHC of J/$\psi$ photoproduction in ultra-peripheral Pb-Pb-collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV. The J/$\psi$ is identified via its dimuon decay in the forward rapidity…
The ALICE collaboration performed the first rapidity-differential measurement of coherent J/$\psi$ photoproduction in ultra-peripheral Pb-Pb collisions at a center-of-mass energy $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV. The J/$\psi$ is detected via…
A partial wave analysis of the $p \bar{p}$ mass-threshold enhancement in the reaction $J/\psi\rightarrow\gamma p\bar{p}$ is used to determine: its $J^{PC}$ quantum numbers to be $0^{-+}$; its peak mass to be below threshold at…