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Related papers: Gamma Emission from Large Galactic Structures

200 papers

Recently, a spatially extended excess of gamma rays collected by the Fermi-LAT from the inner region of the Milky Way has been detected by different groups and with increasingly sophisticated techniques. Yet, any final conclusion about the…

High Energy Astrophysical Phenomena · Physics 2015-02-11 Francesca Calore , Ilias Cholis , Christoph Weniger

The inner region of the Milky Way is one of the most interesting and complex regions of the gamma-ray sky. The intense interstellar emission and resolved point sources, as well as potential contributions by other sources such as unresolved…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Troy A. Porter , Simona Murgia

The Galactic gamma-ray diffuse emission (GDE) is emitted by cosmic rays (CRs), ultra-relativistic protons and electrons, interacting with gas and electromagnetic radiation fields in the interstellar medium. Here we present the analysis of…

Gamma-ray emission produced by interactions between cosmic rays (CRs) and interstellar gas traces the product of their densities throughout the Milky Way. The outer Galaxy is a privileged target of investigation to separate interstellar…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Luigi Tibaldo , Isabelle A. Grenier , Tsunefumi Mizuno

Gamma-ray data from Fermi-LAT reveal a bi-lobular structure extending up to 50 degrees above and below the galactic centre, which presumably originated in some form of energy release there less than a few million years ago. It has been…

High Energy Astrophysical Phenomena · Physics 2011-08-26 Philipp Mertsch , Subir Sarkar

The Fermi bubbles are two large structures in the gamma-ray sky extending to $55^\circ$ above and below the Galactic center. We analyze 50 months of Fermi Large Area Telescope data between 100 MeV and 500 GeV above $10^\circ$ in Galactic…

High Energy Astrophysical Phenomena · Physics 2014-09-22 LAT Collaboration

Fermi has discovered two giant gamma-ray-emitting bubbles that extend nearly 10kpc in diameter north and south of the galactic center (GC). The existence of the bubbles was first evidenced in X-rays detected by ROSAT and later WMAP detected…

High Energy Astrophysical Phenomena · Physics 2015-05-27 K. S. Cheng , D. O. Chernyshov , V. A. Dogiel , C. -M. Ko , W. -H. Ip

We study a scenario in which the Fermi bubbles are formed through a Galactocentric outflow of gas and pre-accelerated cosmic-rays (CR). We take into account CR energy losses due to proton-proton interactions with the gas present in the…

High Energy Astrophysical Phenomena · Physics 2018-10-29 Gwenael Giacinti , Andrew M. Taylor

The discovery of the Fermi bubbles---a huge bilobular structure seen in GeV gamma-rays above and below the Galactic center---implies the presence of a large reservoir of high energy particles at $\sim 10 \, \text{kpc}$ from the disk. The…

High Energy Astrophysical Phenomena · Physics 2019-02-27 Philipp Mertsch , Vahé Petrosian

After the discovery of Fermi Bubbles and the excess of gamma-ray emission, the Galactic Centre has received increasing attention with the aim to understand its role in the origin and acceleration of primary cosmic rays (CRs). Based on a…

High Energy Astrophysical Phenomena · Physics 2020-06-15 Rita C. Anjos , Fernando Catalani

Recent studies have found a positive correlation between the star-formation rate of galaxies and their gamma-ray luminosity. Galaxies with a high star-formation rate are expected to produce a large amount of high-energy cosmic rays, which…

High Energy Astrophysical Phenomena · Physics 2016-08-17 Cesar Rojas-Bravo , Miguel Araya

We report on observations of the Large Magellanic Cloud with the Fermi Gamma-Ray Space Telescope. The LMC is clearly detected with the Large Area Telescope (LAT) and for the first time the emission is spatially well resolved in gamma-rays.…

High Energy Astrophysical Phenomena · Physics 2009-05-18 Jürgen Knödlseder

This paper deals with the cosmic-ray penetration into molecular clouds and with the related gamma--ray emission. High energy cosmic rays interact with the dense gas and produce neutral pions which in turn decay into two gamma rays. This…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Stefano Gabici

The origin of Galactic cosmic rays (with energies up to 10^15 eV) remains unclear, though it is widely believed that they originate in the shock waves of expanding supernova remnants. Currently the best way to investigate their acceleration…

Astrophysics · Physics 2012-08-27 The H. E. S. S. Collaboration , : , F. A. Aharonian

Cosmic rays travel throughout the Galaxy, leaving traces from radio to ultra-high-energy gamma rays due to interactions with the interstellar gas, radiation field and magnetic field. Therefore, it is necessary to utilize multi-wavelength…

High Energy Astrophysical Phenomena · Physics 2024-03-15 Xin-Yu He , Pei-Pei Zhang , Qiang Yuan , Yi-Qing Guo

The distribution of cosmic rays in the Galaxy at energies above few TeVs is still uncertain and this affects the expectations for the diffuse gamma flux produced by hadronic interactions of cosmic rays with the interstellar gas. We show…

High Energy Astrophysical Phenomena · Physics 2020-01-08 M. Cataldo , G. Pagliaroli , V. Vecchiotti , F. L. Villante

The recent IceCube detection of significant neutrino flux from the inner Galactic plane has provided us valuable insights on the spectrum of cosmic rays in our Galaxy. This flux can be produced either by a population of Galactic point…

High Energy Astrophysical Phenomena · Physics 2024-06-04 Abhijit Roy , Jagdish C. Joshi , Martina Cardillo , Prantik Sarmah , Ritabrata Sarkar , Sovan Chakraborty

Motivated by the discovery of the non-thermal Fermi bubble features both below and above the Galactic plane, we investigate a scenario in which these bubbles are formed through Galacto-centric outflow. Cosmic rays (CR) both diffusing and…

High Energy Astrophysical Phenomena · Physics 2017-01-11 Andrew M. Taylor , Gwenael Giacinti

The standard approach to cosmic-ray (CR) propagation in the Galaxy is based on the assumption that local transport properties can be extrapolated to the whole CR confining volume. Such models tend to underestimate the gamma-ray flux above…

High Energy Astrophysical Phenomena · Physics 2015-05-06 Daniele Gaggero , Alfredo Urbano , Mauro Valli , Piero Ullio

Diffuse gamma-ray radiation in galaxies is produced by cosmic ray interactions with the interstellar medium. With the completion of EGRET observations, the only extragalactic object from which there has been a positive detection of diffuse…

Astrophysics · Physics 2009-11-06 Vasiliki Pavlidou , Brian D. Fields