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Related papers: Cosmic-ray diffusion in two local filamentary clou…

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The diffuse Galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray…

High Energy Astrophysical Phenomena · Physics 2010-04-23 LAT Collaboration

We study the effect of cosmic ray (CR) acceleration in the massive compact star cluster Westerlund 1 in light of its recent detection in $\gamma$-rays. Recent observations reveal a $1/r$ radial distribution of the CR energy density. Here we…

High Energy Astrophysical Phenomena · Physics 2022-01-19 Sourav Bhadra , Siddhartha Gupta , Biman B. Nath , Prateek Sharma

A correct description of cosmic-ray (CR) diffusion in turbulent plasma is essential for many astrophysical and heliospheric problems. This paper aims to present physical diffusion behavior of CRs in actual turbulent magnetic fields, model…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Siyao Xu , Huirong Yan

The diffuse Galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray…

High Energy Astrophysical Phenomena · Physics 2019-08-13 T. A. Porter

The "GeV-excess" of the diffuse gamma-rays in the halo is studied with a template fit based on energy spectra for each possible process of gamma-ray emission. Such a fit allows to determine the background and signal simultaneously, so the…

High Energy Astrophysical Phenomena · Physics 2016-10-28 Wim de Boer , Iris Gebauer , Alexander Neumann , Peter L. Biermann

Star-forming regions on different scales, such as giant molecular clouds in our Galaxy and star-forming galaxies, emit GeV gamma-rays. These are thought to originate from hadronic interactions of cosmic-ray (CR) nuclei with the interstellar…

High Energy Astrophysical Phenomena · Physics 2019-01-16 Fang-Kun Peng , Shao-Qiang Xi , Xiang-Yu Wang , Qi-Jun Zhi , Di Li

Fluid approximations to cosmic ray (CR) transport are often preferred to kinetic descriptions in studies of the dynamics of the interstellar medium (ISM) of galaxies, because they allow simpler analytical and numerical treatments.…

High Energy Astrophysical Phenomena · Physics 2019-06-04 L. F. S. Rodrigues , A. P. Snodin , G. R. Sarson , Anvar Shukurov

Simulations of Galactic CR transport were performed with the software GALPROP, with the resulting gamma-ray flux calculated up to the PeV regime. The impact of altering parameters such as the number and distribution of CR sources, the…

High Energy Astrophysical Phenomena · Physics 2025-04-29 Peter Marinos

We have developed a model which aims to reproduce observational data of many kinds related to cosmic-ray (CR) origin and propagation: direct measurements of nuclei, antiprotons, electrons and positrons, gamma-rays, and synchrotron…

Astrophysics · Physics 2009-10-31 I. V. Moskalenko , A. W. Strong

Cosmic rays (CRs) can be studied through the galaxy-wide gamma-ray emission that they generate when propagating in the interstellar medium. The comparison of the diffuse signals from different systems may inform us about the key parameters…

High Energy Astrophysical Phenomena · Physics 2010-12-10 LAT collaboration

The diffusion of cosmic rays (CRs) in turbulent magnetic fields is fundamental to understand various astrophysical processes. We explore the CR diffusion in the magnetic fluctuations amplified by the nonlinear turbulent dynamo, in the…

High Energy Astrophysical Phenomena · Physics 2024-12-03 Chao Zhang , Siyao Xu

Cosmic rays (CRs) are an integral component of the interstellar medium, producing broadband emission while interacting with other Galactic matter components like the interstellar gas or magnetic fields. In addition to observations,…

High Energy Astrophysical Phenomena · Physics 2022-10-12 Julia Thaler , Ralf Kissmann , Olaf Reimer

We investigate the interplay of cosmic ray (CR) propagation and advection in galaxy clusters. Propagation in form of CR diffusion and streaming tends to drive the CR radial profiles towards being flat, with equal CR number density…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Torsten A. Ensslin , Christoph Pfrommer , Francesco Miniati , Kandaswamy Subramanian

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

We present initial results from the first optical spectroscopic survey of high latitude Galactic cirrus clouds. The observed shape of the cirrus spectrum does not agree with that of scattered ambient Galactic starlight. This mismatch can be…

Astrophysics · Physics 2009-10-30 Arpad Szomoru , Puragra Guhathakurta

The pair of large radio lobes in the Virgo cluster, each about 23 kpc in radius, have curiously sharp outer edges where the radio-synchrotron continuum flux declines abruptly. However, just adjacent to this sharp transition, the radio flux…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 William G. Mathews , Fulai Guo

Context: Diffuse $\gamma$-ray emission from cosmic ray (CR) protons scattering off the gas in the intracluster and intergalactic medium (ICM and IGM) remains out of reach for current observations. Detecting this emission would provide…

High Energy Astrophysical Phenomena · Physics 2025-10-20 Ludwig M. Böss , Ildar Khabibullin , Daniel Karner , Klaus Dolag , Ulrich P. Steinwandel , Elena Hernandez-Martinez , Jenny G. Sorce

Recent observations with the MeerKAT radio telescope reveal a unique population of faint non-thermal filaments pervading the central molecular zone (CMZ). Some of those filaments are organized into groups of almost parallel filaments,…

High Energy Astrophysical Phenomena · Physics 2020-02-26 Timon Thomas , Christoph Pfrommer , Torsten A. Enßlin

Fermi/LAT observations of star-forming galaxies in the ~0.1-100GeV range have made possible a first population study. Evidence was found for a correlation between gamma-ray luminosity and tracers of the star formation activity. Studying…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Pierrick Martin

Modern X-ray and $\gamma$-ray instruments are revealing a growing class of Galactic non-thermal sources whose emission centroids are measurably offset from the nearest plausible sites of cosmic ray (CR) acceleration. Such "displaced"…

High Energy Astrophysical Phenomena · Physics 2026-03-13 Manami Roy , Mark R. Krumholz , Roland M. Crocker , Todd A. Thompson