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Related papers: Molecular Clouds as Cosmic Ray Laboratories

200 papers

Many star-forming galaxies and those hosting active galactic nuclei (AGN) show evidence of massive outflows of material in a variety of phases including ionized, neutral atomic, and molecular. Molecular outflows in particular have been the…

High Energy Astrophysical Phenomena · Physics 2023-02-15 Alex McDaniel , Marco Ajello , Chris Karwin

Galactic cosmic rays are believed to be accelerated at supernova remnants via diffusive shock acceleration. Though this mechanism gives fairly robust predictions for the spectrum of particles accelerated at the shock, the spectrum of the…

High Energy Astrophysical Phenomena · Physics 2011-08-25 Stefano Gabici

Cosmic rays are a fundamental source of ionization for molecular and diffuse clouds, influencing their chemical, thermal, and dynamical evolution. The amount of cosmic rays inside a cloud also determines the $\gamma$-ray flux produced by…

High Energy Astrophysical Phenomena · Physics 2015-09-18 G. Morlino , S. Gabici , J. Krause

Supernova remnants interacting with molecular clouds are potentially exciting systems in which to detect evidence of cosmic ray acceleration. Prominent gamma-ray emission is produced via the decay of neutral pions when cosmic rays encounter…

High Energy Astrophysical Phenomena · Physics 2014-11-20 John W. Hewitt , Farhad Yusef-Zadeh , Mark Wardle

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 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

The magnetic fields that emerge from beneath the solar surface and permeate the solar atmosphere are the key drivers of space weather and, thus, understanding them is important to human society. Direct observations, used to measure magnetic…

Solar and Stellar Astrophysics · Physics 2024-05-29 Kenny C. Y. Ng , Andrew Hillier , Shin'ichiro Ando

Supernova remnants interacting with molecular clouds are ideal laboratories to study the acceleration of particles at shock waves and their transport and interactions in the surrounding interstellar medium. In this paper, we focus on the…

High Energy Astrophysical Phenomena · Physics 2020-03-04 V. H. M. Phan , S. Gabici , G. Morlino , R. Terrier , J. Vink , J. Krause , M. Menu

The diffuse gamma-ray emission from the Milky Way serves as a crucial probe for understanding the propagation and interactions of cosmic rays within our galaxy. The Galactic diffuse gamma-ray emission between 10 TeV and 1 PeV has been…

High Energy Astrophysical Phenomena · Physics 2025-01-07 Jiayin He , Houdun Zeng , Yi Zhang , Qiang Yuan , Rui Zhang , Jun Li

The cosmic gamma-ray background radiation is one of the most fundamental observables in the gamma-ray band. Although the origin of the cosmic gamma-ray background radiation has been a mystery for a long time, the Fermi gamma-ray space…

High Energy Astrophysical Phenomena · Physics 2014-12-15 Yoshiyuki Inoue

The contribution of the Source Cosmic Rays (SCRs), confined in Supernova Remnants, to the diffuse high energy \gr emission above 1 GeV from the Galactic disk is studied. \grs produced by the SCRs have a much harder spectrum compared with…

Astrophysics · Physics 2010-12-03 Evgeny G. Berezhko , Heinrich J. Voelk

The Galactic diffuse gamma-ray emission is conventionally modeled as the product of cosmic-ray interactions with the interstellar medium. However, the cumulative contribution of stellar atmospheres acting as hadronic interaction targets…

High Energy Astrophysical Phenomena · Physics 2026-04-14 Yanbo Wang , Zhenglong Wang , Rui Zhang , Yi Zhang

Galactic diffuse emissions in gamma rays and neutrinos arise from interactions of cosmic rays with the interstellar medium and probe the cosmic-ray intensity away from the Solar system. Model predictions for those are influenced by the…

High Energy Astrophysical Phenomena · Physics 2026-03-11 Anton Stall , Philipp Mertsch

Cosmic Rays (CRs) propagating through dense molecular clouds (MCs) produce gamma rays which carry direct information about the CR distribution throughout the Galaxy. Observations of gamma rays in different energy bands allow exploration of…

High Energy Astrophysical Phenomena · Physics 2022-03-14 Giada Peron , Felix Aharonian

In the past few years, gamma-ray astronomy has entered a golden age. At TeV energies, only a handful of sources were known a decade ago, but the current generation of ground-based imaging atmospheric Cherenkov telescopes has increased this…

High Energy Astrophysical Phenomena · Physics 2017-08-23 Marianne Lemoine-Goumard

We report the current status of the observations of supernova remnants (SNRs) with the Large Area Telescope (LAT) aboard the Fermi Gamma-ray Space Telescope, focusing on middle-aged SNRs that appear to be interacting with molecular clouds.…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Yasunobu Uchiyama

We investigate hypernova (hyper-energetic supernova) and gamma-ray burst (GRB) remnants in our Galaxy as TeV gamma-ray sources, particularly in the role of potential TeV unidentified sources, which have no clear counterpart at other…

High Energy Astrophysical Phenomena · Physics 2015-04-23 Kunihito Ioka , Peter Meszaros

Particle acceleration in the dynamically evolving environment of Supernova Remnants is discussed in the framework of a genuinely time-dependent nonlinear theory, assuming spherical symmetry. As a consequence the dependence of injection on…

Astrophysics · Physics 2007-05-23 H. J. Voelk

Context. Star-forming galaxies emit {\gamma}rays with relatively low luminosity, but the study of their emission is no less captivating. While it is known that their {\gamma}-ray luminosity in the GeV band is strongly linked to their star…

High Energy Astrophysical Phenomena · Physics 2025-07-02 P. Kornecki , J. Biteau , C. Boisson , P. Cristofari

"Diffuse" gamma rays consist of several components: truly diffuse emission from the interstellar medium, the extragalactic background, whose origin is not firmly established yet, and the contribution from unresolved and faint Galactic point…

Astrophysics · Physics 2015-06-24 I. V. Moskalenko , A. W. Strong , O. Reimer