Related papers: Charmonium suppression in p-A collisions
We present measurements of charmonium and bottomonium production using a data sample collected by CDF during the 1992-93 p-pbar collider run at the Fermilab Tevatron.
The production of the charmonium states in hadronic experiments is considered in NLO at the strong coupling constant. It is shown, that such an approach solves some significant problems, arising when only leading order processes are…
We study the excitation function of the low-lying charmonium state: $\Psi$(3686) in $\bar p$ Au collisions taking into account their in-medium propagation. The time evolution of the spectral functions of the charmonium state is studied with…
We study the production of the exotic charged charmonium-like state $Z_c^{\pm}(3900)$ in $p \bar p$ collisions through the sequential process $\psi(4260) \rightarrow Z_c^{\pm}(3900) \pi^{\mp}$, $Z_c^{\pm}(3900) \rightarrow J/\psi…
Direct, resonant production of the charmonium states $\chi_{c1}$ and $\chi_{c2}$ in electron-positron annihilation is investigated. Depending on details of the model, a sizeable variation of the prediction for the production cross section…
We show that the predicted primordial helium production is significantly reduced when new measurements of the neutron lifetime and the implied enhancement in the weak reaction rates are included in big-bang nucleosynthesis. Therefore, even…
It is shown that the nuclear shadowing of charmonium due to the modification of the nuclear parton distribution is similar in the factorization approach based on non relativistic QCD and in the color evaporation model. In the first model, a…
Some recent results from the Fermilab fixed-target experiment E789 on production of charm, charmonium, and beauty are summarized and compared to model predictions. The data indicate that heavy-quark and quarkonium production are not yet…
The charmonium-like states, Y(4260), Y(4350), produced via initial state radiation, as well as the X(3872), and Y(3940), produced in B meson decays from the BABAR B-factory are reviewed. These mesons do not seem consistent with conventional…
Charmonia hadro- and photo-production are analyzed in the framework of the color-octet model taking into account higher-order effects induced by initial-state radiation of gluons. We argue that color-octet matrix elements obtained from…
We present the gluon-gluon and photon-gluon helicity amplitudes for color singlet and octet charmonium production in polarized and unpolarized hadron-hadron and photon-hadron collisions.
We propose a parametrization of the nuclear absorption mechanism relying on the proper time spent by $c\overline{c}$ bound states travelling in nuclear matter. Our approach could lead to the extraction of charmonium formation time. It is…
We report our latest results on charmonium suppression as measured at the CERN-SPS in Pb-Pb interactions at an incident beam momentum of 158 GeV/c per nucleon. Preliminary results obtained from the most recent sample of data collected in…
Due to coherence, there are strong electromagnetic fields of short duration in very peripheral collisions. They give rise to photon-photon and photon-nucleus collisions with a high flux up to an invariant mass region hitherto unexplored…
In e^+e^- annihilation at \sqrt{s}=10.6 GeV Belle Collaboration found, that J/psi mesons are predominantly produced in association with an extra \bar{c}c pair. The possible mechanisms of J/psi production are discussed and the probability of…
The masses of the low lying charmonium states, namely, the $J/\Psi$, $\Psi(3686)$, and $\Psi(3770)$ are shifted downwards due to the second order Stark effect. In $\bar p + \text{Au}$ collisions at $6-10$ GeV we study their in\,-\,medium…
I review some central physics opportunities at the 15 ... 30 GeV continuous beam electron accelerator ELFE, proposed to be built in conjunction with the DESY linear collider. Our present detailed knowledge of single parton distributions in…
We study the charmonium suppression in different evolutions of quark gluon plasma (QGP) based on the transport model. In the colliding energies of Large Hadron Collider, charmonium final yields are dominated by the recombination of charm…
We present the first predictions for sub-threshold open charm and charmonium production in nuclear collisions. The production mechanism is driven by multi-step scatterings of nucleons and their resonance states, accumulating sufficient…
We study the production of heavy quarkonium states in high energy proton-nucleus collisions. Following earlier work of Blaizot, Fujii, Gelis, and Venugopalan, we systematically include both small $x$ evolution and multiple scattering…