English
Related papers

Related papers: Parameterization of the Angular Distribution of Ga…

200 papers

A general expression for the double differential cross section of fluorescence radiation following photorecombination (PRF) of polarized electrons and polarized ions is derived by using usual atomic theory methods and is represented in the…

Atomic Physics · Physics 2009-11-11 A. Kupliauskiene

We improve the description of pion-photon interactions in the radiative return process $e^+e^-\to \pi^+\pi^-\gamma$ at the next-to-leading order by including the pion form factor in the Feynman rules. We present a general calculation of the…

High Energy Physics - Phenomenology · Physics 2026-03-16 Pau Petit Rosàs , Olga Shekhovtsova , William J. Torres Bobadilla

We compute the angular two-point correlation functions of the gamma-ray bursts at cosmological distances. Since the gamma-ray burst emission mechanism is not yet established, we simply assume that the gamma-ray burst sources are associated…

Astrophysics · Physics 2009-10-22 Shiho Kobayashi , Shin Sasaki , Yasushi Suto

A multi-dimension, time-dependent Monte Carlo code is used to compute sample gamma-ray spectra to explore whether unambiguous constraints could be obtained from gamma-ray observations of Type Ia supernovae. Both spherical and aspherical…

Astrophysics · Physics 2009-11-13 S. A. Sim , P. A. Mazzali

We study the diffractive production of photons in gamma-p and gamma-gamma collisions. We specifically compute the rates for gamma*-p -> gamma-X and for gamma*-gamma* -> gamma-gamma, where X denotes the proton dissociation. We focus on the…

High Energy Physics - Phenomenology · Physics 2008-11-26 N. G. Evanson , J. R. Forshaw

Recent data on photoproduction of $\eta'$ mesons off protons have been included in the data base for the Bonn-Gatchina partial wave analysis. The real and imaginary parts of the $S$-wave $\eta^\prime p\to \eta^\prime p$ scattering amplitude…

Nuclear Experiment · Physics 2018-11-14 A. V. Anisovich , V. Burkert , M. Dugger , E. Klempt , V. A. Nikonov , B. G. Ritchie , A. V. Sarantsev , U. Thoma

Gamma-ray spectroscopy provides diagnostics of particle acceleration in solar flares, but care must be taken when interpreting the spectra due to effects of the angular distribution of the accelerated particles (such as relativistic…

Solar and Stellar Astrophysics · Physics 2015-05-20 Shichao Tang , David M. Smith

The pp -> pp gamma reaction has been studied at a beam energy of 310 MeV by detecting both final protons at the PROMICE-WASA facility and identifying the photon through the resulting missing-mass peak. The photon angular distribution in the…

Nuclear Experiment · Physics 2011-05-19 A. Johansson , H. Haberzettl , K. Nakayama , C. Wilkin

Cosmic ray data may allow the determination of the proton-air cross section at ultra-high energy. For example, the distribution of the first interaction point in air showers reflects the particle production cross section. As it is not…

Astrophysics · Physics 2007-09-11 Ralf Ulrich , Johannes Bluemer , Ralph Engel , Fabian Schuessler , Michael Unger

We show that the transverse-mass and rapidity spectra of protons and pions produced in Au-Au collisions at sqrt(sNN) = 2.4 GeV can be well reproduced in a thermodynamic model assuming single freeze-out of particles from a spherically…

Nuclear Theory · Physics 2021-02-23 Sz. Harabasz , W. Florkowski , T. Galatyuk , M. Gumberidze , R. Ryblewski , P. Salabura , J. Stroth

The Milky Way has been estabished to emit gamma rays. These gamma rays are presumably dominated by decays of neutral pions, although inverse Compton scatterings and bremsstrahlung also contribute. It is plausible that other galaxies can be…

Astrophysics · Physics 2009-11-13 Niklas Karlsson

Motivated by the renewed interest in studying the pion production on nuclei with protons at few GeV incident energies, we investigate the pion production in proton-proton collisions over an energy range of 300 $MeV$ to 2 $GeV$. Starting…

Nuclear Theory · Physics 2009-10-30 A. Engel , A. K. Dutt-Mazumder , R. Shyam , U. Mosel

Cosmic sources of gamma-ray radiation in the GeV range are often characterized by violent variability, in particular this concerns blazars, gamma-ray bursts, and the pulsar wind nebula Crab. Such gamma-ray emission requires a very efficient…

High Energy Astrophysical Phenomena · Physics 2018-08-03 Krzysztof Nalewajko

Within an effective Lagrangian model, we present calculations for cross sections of the dilepton production in proton-proton and proton-neutron collisions at laboratory kinetic energies in 1-5 GeV range. Production amplitudes include…

High Energy Physics - Phenomenology · Physics 2009-11-10 R. Shyam , U. Mosel

The Cherenkov light produced in air showers largely contributes to the signal observed in ground-based gamma-ray and cosmic-ray observatories. Yet, no description of this phenomenon is available covering both regions of small and large…

High Energy Astrophysical Phenomena · Physics 2021-03-17 Luan Arbeletche , Vitor de Souza

In an unconventional presentation of the data on the transverse momentum spectra of baryons produced in heavy-ion collisions, regularities are found that make possible the discovery of a universal formula valid for $p, \Lambda, \Xi$ and…

Nuclear Experiment · Physics 2018-05-23 Rudolph C. Hwa , Lilin Zhu

One of the most important unresolved issues in gamma-ray burst physics is the origin of the prompt gamma-ray spectrum. Its general non-thermal character and the softness in the X-ray band remain unexplained. We tackle these issues by…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Atul Chhotray , Davide Lazzati

In this paper, we investigate the gamma ray signal produced from dark matter collisions with high energy cosmic protons. Notably, we extend past results by including important hadronization effects. Showering and hadronization produces a…

High Energy Astrophysical Phenomena · Physics 2013-03-11 Spencer Chang , Yu Gao , Michael Spannowsky

Two-particle angular correlation is one of the most powerful tools to study the mechanism of particle production in proton--proton (pp) collision systems by relating the difference between the azimuthal angle ($\Delta\varphi$) and the…

Nuclear Experiment · Physics 2024-02-14 Daniela Ruggiano

The $\gamma$-ray observation of interstellar gas provides a unique way to probe the cosmic rays (CRs) outside the solar system. In this work, we use an updated version of Fermi-LAT data and recent multi-wavelength tracers of interstellar…

High Energy Astrophysical Phenomena · Physics 2019-06-19 Zhao-Qiang Shen , Xiaoyuan Huang , Qiang Yuan , Yi-Zhong Fan , Da-Ming Wei