相关论文: Two-Photon Processes at Intermediate Energies
The inclusive production of hadrons through electroweak currents can be rigorously analysed with short-distance theoretical tools. The associated observables are insensitive to the involved infrared behaviour of the strong interaction,…
The strong electromagnetic fields carried by relativistic highly charged ions make heavy-ion colliders attractive places to study photonuclear interactions and two-photon interactions. At RHIC, three experiments have studied coherent…
The meson production cross sections are estimated considering photon-photon interactions in hadron - hadron collisions at CERN LHC energies. We consider a large number of mesons with photon-photon partial decay width well constrained by the…
We review our results on a new class of $2 \to 3$ exclusive processes, as a probe of both chiral-even and chiral-odd quark GPDs. We consider the exclusive photoproduction of a photon-meson pair, in the kinematics where the pair has a large…
Multiple polarization observables must be measured to access the amplitude structure of pseudoscalar meson photoproduction off the proton. The hyperon-producing reactions are especially attractive to study, since the weak decays allow…
The exclusive production of baryon-antibaryon pairs in the collisions of two quasi-real photons has been studied using different detectors at e+e- colliders. Results are presented for $\gamma\gamma\to$ proton antiproton,…
Light, beyond-the-standard-model particles $X$ in the 1-100 MeV mass range can be produced in nuclear and hadronic reactions but would have to decay electromagnetically. We show that simple and well-understood low-energy hadronic processes…
Enlarging the set of hard exclusive reactions to be studied in the framework of QCD collinear factorization opens new possibilities to access generalized parton distributions (GPDs). We studied the photoproduction of a large invariant mass…
We discuss the production of hadronic resonances in very peripheral heavy ion collisions, where the ions collide with impact parameter larger than twice the nuclear radius and remain intact after the collision. We compare the resonance…
We present an exploratory study of two pion photo-- and electroproduction off the nucleon in the threshold region. To calculate the pertinent amplitudes, we make use of heavy baryon chiral perturbation theory. We show that due to finite…
We have investigated the single and double diffractive production of dileptons and photons in ultra-peripheral collisions at the Large Hadron Collider (LHC). Utilizing advanced theoretical models that integrate quantum electrodynamics (QED)…
The cross section of top pair production in hadronic collisions to O(alpha \alpha_s^2) is calculated within the General 2-Higgs-Doublet Model and the Minimal Supersymmetric Standard Model. At the parton level the O(alpha) one-loop…
We calculate electromagnetic production from highly excited hadronic matter created in heavy ion collisions. The rates include the usual lowest order processes in quark-gluon plasma plus the usual reactions in the hadronic phase, related…
We calculate the production of real photons in relativistic nuclear collisions at RHIC, consistently with the quenching of fast partons. We go beyond one-body observables, and evaluate photon-triggered fragmentation functions, in the…
In this paper we analyse the double vector meson production in photon -- hadron ($\gamma h$) interactions at $pp/pA/AA$ collisions and present predictions for the $\rho\rho$, $J/\Psi J/\Psi$ and $\rho J/\Psi$ production considering the…
The dynamics of partonic cascades may be an important aspect for particle production in relativistic collisions of nuclei at CERN SPS and BNL RHIC energies. Within the Parton-Cascade Model, we estimate the production of single photons from…
Due to the coherence of all the protons in a nucleus, there are very strong electromagnetic fields of short duration in relativistic heavy ion collisions. They give rise to quasireal photon-photon and photon-nucleus collisions with a large…
Differences in the photoproduction of mesons on the free proton and on nuclei are expected to reveal changes in the properties of hadrons. Inclusive studies of nuclear photoabsorption have provided evidence of medium modifications. However,…
Isolated photons at hadron colliders are defined by permitting only a limited amount of hadronic energy inside a fixed-size cone around the candidate photon direction. This isolation criterion admits contributions from collinear photon…
We present a theoretical study of a double lepton pair production in ultra--relativistic collision between two bare ions. Special emphasis is placed to processes in which creation of (at least one) $e^+ e^-$ pair is accompanied by the…