Related papers: Parameterization of the Angular Distribution of Ga…
An experiment on the radiative pi^+ meson photoproduction from the proton (gamma p->gamma pi^+ n) was carried out at the Mainz Microtron MAMI in the kinematic region 537 MeV <E_{gamma}<817 MeV, 140^o<theta_{gamma-gamma'}^cm<180^o. The pi^+…
We examine diffractive proton-proton scattering p p -> p X and photo- and electroproduction of \rho^0 mesons \gamma^(*) p -> \rho^0 X, where X denotes a proton or a final state, into which the proton can go by diffractive dissociation.…
Gamma-rays can be produced by the interaction of a relativistic jet and the matter of the stellar wind in the subclass of massive X-ray binaries known as "microquasars". The relativistic jet is ejected from the surroundings of the compact…
New developments in empirical analyses of the proton-proton differential cross section data at high energies are reported. Making use of an unconstrained model-independent parametrization for the scattering amplitude and two different fit…
Polarization spectra had been predicted within the photosphere model. For the purpose of seeking more clues to distinguish between the models, both the time-resolved and time-integrated polarization spectra from optical band to MeV…
The GlueX experiment at Jefferson Lab has observed $p\bar{p}$ and, for the first time, $\Lambda\bar{\Lambda}$ and $p\bar{\Lambda}$ photoproduction from a proton target at photon energies up to 11.6 GeV. The angular distributions are forward…
The angular dependence of proton-proton correlation functions is studied in central $^{40}Ca+^{40}Ca$ and $^{48}Ca+^{48}Ca$ nuclear reactions at E=80 MeV/A. Measurements were performed with the HiRA detector complemented by the 4$\pi$ Array…
Recent observations by the H.E.S.S. collaboration of the Galactic Centre region have revealed what appears to be gamma-ray emission from the decay of pions produced by interactions of recently accelerated cosmic rays with local molecular…
The physics scope of polarized nucleon-nucleon collisions originating from an internal polarized target in the HERA proton beam is summarized. Based on 240 pb^{-1} integrated luminosity at 40 GeV c.m. energy, statistical sensitivities are…
The parametric fluorescence from a nonlinear crystal forms a conical radiation pattern. We measure the angular and spectral distributions of parametric fluorescence in a beta-barium borate crystal pumped by a 405-nm diode laser employing…
A fundamental problem of cosmic ray (CR) physics is the determination of the average properties of Galactic CRs outside the Solar system. Starting from COS-B data in the 1980's, gamma-ray observations of molecular clouds in the Gould Belt…
The problem of electromagnetic emission generation in plasma with electron beams is relevant both for practical applications and for interpretation of radio emission processes in astrophysical systems. In this work, we consider the case of…
We investigate the pp --> pp eta and pn --> pn eta reactions within an effective Lagrangian model for laboratory kinetic energies ranging from very close to eta meson production threshold to about 10 GeV. Production amplitudes include…
Incoherent photon emission by ultrarelativistic electrons in the normal incidence of a laser pulse on a foil is investigated by means of three-dimensional numerical simulations in the range of intensities $2 \times 10^{21} \text{--} 2…
The photoproduction of $f_1(1285)$ meson off proton is investigated within an effective Lagrangian approach. The $t$-channel $\rho$- and $\omega$-exchange diagrams, $u$-channel nucleon-exchange diagram, generalized contact term, and…
The cross section for polarized and unpolarized electron-proton scattering is calculated taking into account radiative corrections in leading and next-to leading logarithmic approximation. The expression of the cross section is formally…
We have observed atmospheric gamma rays from 30GeV to 8TeV, using emulsion chambers at balloon altitudes, accumulating the largest total exposure in this energy range to date, SOT ~ 6.66m^2.sr.day. At very high altitudes, with residual…
Contrary to very early beliefs, the experimental cross section data for the eta production in proton-proton scattering are well described if pi and only eta meson exchange diagrams are used to calculate the Born term. The inclusion of…
The propagation of $\gamma$ rays over very large distances provides new insights on the intergalactic medium and on fundamental physics. On their path to the Earth, $\gamma$ rays can annihilate with diffuse infrared or optical photons of…
Resonances just above the proton threshold in 30S affect the 29P(p,gamma)30S reaction under astrophysical conditions. The (p,gamma)-reaction rate is currently determined indirectly and depends on the properties of the relevant resonances.…