Related papers: Probing proton halos through pion photoproduction
I study the production of prompt photons in polarized hadronic collisions, considering different isolation prescriptions. In particular, I focus on the problem of the measurability of the polarized gluon density in the proton through…
Elastic $\rho^0$ photoproduction has been measured using the ZEUS detector at HERA. Untagged photoproduction events from $ep$ interactions were used to measure the reaction $\gamma p \rightarrow \rho^0 p$ ($\rho^0 \rightarrow \pi^+ \pi^-$)…
We investigate threshold pion photoproduction in the framework of heavy baryon chiral perturbation theory. We give the expansion of the electric dipole amplitude $E_{0+}$ to three orders in $\mu$, the ratio of the pion to nucleon mass, and…
Little information is known about the polarization of gluons inside a longitudinally polarized proton. I report on the sensitivity of photoproduction experiments to it. Both jet and heavy quark production are considered.
We investigate the possibility that the process of $\rho^{0}$-meson photoproduction on proton, $\gamma+p\to p+\rho^{0}$, in the near threshold region $E_{\gamma}< 2$ GeV, can be considered in the framework of model with $\pi$-, $\sigma$-…
The production of hard photons and neutral pions in 190 MeV proton induced reactions on C, Ca, Ni, and W targets has been for the first time concurrently studied. Angular distributions and energy spectra up to the kinematical limit are…
The polarization observables in phi meson photoproduction is studied to probe the strangeness content of the nucleon. In addition to the dominant diffractive production and the one-pion-exchange process, we take into account the direct…
Photoproduction of neutral pions has been studied with the CBELSA/TAPS detector in the reaction $\gamma p\to p\pi^0$ for photon energies between 0.85 and 2.50 GeV. The $\pi^0$ mesons are observed in their dominant neutral decay mode:…
Nuclear capture of antiprotons from atomic states is studied. Partial widths for single nucleon capture events leading to cold residual nuclei are calculated. Recent CERN experiments that compare the neutron and proton captures are…
Hard, or high transverse momentum, pion photoproduction can be a tool for probing the parton structure of the beam and target. We discuss the perturbative and soft processes that contribute, and show how regions where perturbative processes…
The 17O(p,g)18F reaction plays an important role in hydrogen burning processes in different stages of stellar evolution. The rate of this reaction must therefore be known with high accuracy in order to provide the necessary input for…
Little information is known about the polarization of gluons inside a longitudinally polarized proton. We investigate the sensitivity of photoproduction experiments with both beam and target longitudinally polarized to the polarization of…
Photoproduction data collected with the H1 detector at HERA in 1994 are used to study the cross-sections for inclusive charged particle production and the structure of the photon. The differential cross-sections dsigma/dpT2, for |eta| < 1…
I discuss few selected topics in heavy flavour photoproduction at HERA which require large integrated luminosity in order to be experimentally investigated. I present phenomenological predictions for bottom production. As a possible…
We present new data for the polarization observables of the final state proton in the $^{1}H(\vec{\gamma},\vec{p})\pi^{0}$ reaction. These data can be used to test predictions based on hadron helicity conservation (HHC) and perturbative QCD…
The sensitivities to anomalous quartic photon couplings at the Large Hadron Collider are estimated using diphoton production via photon fusion. The tagging of the protons proves to be a very powerful tool to suppress the background and…
We investigate the formation cross sections of the deeply bound pionic atoms on halo nuclei theoretically. We consider one-neutron pick-up (d,3He) reaction for the pionic atom formation and find that the formation rate is significantly…
Using a model for two pion photoproduction on the proton previously tested in total cross sections and invariant mass distributions, we evaluate here polarization observables on which recent experiments are providing new information. We…
Single pi0 photoproduction has been studied with the CB-ELSA experiment at Bonn using tagged photon energies between 0.3 and 3.0 GeV. The experimental setup covers a very large solid angle of about 98% of 4 pi. Differential cross sections…
A Regge model with absorptive corrections is employed in a global analysis of the world data on the reactions gamma p -> pi0 p and gamma n -> pi0 n for photon energies from 3 to 18 GeV. In this region resonance contributions are expected to…