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Related papers: Molecular Clouds as Cosmic-Ray Barometers

200 papers

Direct measurements of cosmic ray (CR) species combined with observations of their associated gamma-ray emissions can be used to constrain models of CR propagation, trace the structure of the Galaxy, and search for signatures of new…

High Energy Astrophysical Phenomena · Physics 2018-04-11 Gudlaugur Johannesson , Troy A. Porter , Igor V. Moskalenko

As recently shown, Fermi-LAT measurements of the diffuse gamma-ray emission from the Galaxy favor the presence of a smooth softening in the primary cosmic-ray spectrum with increasing Galactocentric distance. This result can be interpreted…

High Energy Astrophysical Phenomena · Physics 2016-06-22 Daniele Gaggero , Dario Grasso , Antonio Marinelli , Alfredo Urbano , Mauro Valli

We present a new reconstruction of the distribution of atomic hydrogen in the inner Galaxy that is based on explicit radiation-transport modelling of line and continuum emission and a gas-flow model in the barred Galaxy that provides…

High Energy Astrophysical Phenomena · Physics 2022-05-11 Martin Pohl , Oscar Macias , Phaedra Coleman , Chris Gordon

Recent submillimeter and far-infrared wavelength observations of absorption in the rotational ground-state lines of various simple molecules against distant Galactic continuum sources have opened the possibility of studying the chemistry of…

Astrophysics of Galaxies · Physics 2017-02-21 B. Winkel , H. Wiesemeyer , K. M. Menten , M. Sato , A. Brunthaler , F. Wyrowski , D. Neufeld , M. Gerin , N. Indriolo

The diffuse emission of gamma-rays and neutrinos, produced by interactions of cosmic rays with interstellar matter in the Milky Way, provides valuable insights into cosmic ray propagation and Galactic processes. Emission models…

Gravitational lensing has now become a popular tool to measure the mass distribution of structures in the Universe on various scales. Here we focus on the study of galaxy's scale dark matter halos with galaxy-galaxy lensing techniques:…

Astrophysics · Physics 2007-05-23 M. Limousin , J-P. Kneib , P. Natarajan

For about two decades, a population of relative small and nearby molecular clouds has been known to exist at high Galactic latitudes. Lying more than 10$^\circ$ from the Galactic plane, these clouds have typical distances of $\sim$150 pc,…

Astrophysics · Physics 2009-11-10 Diego F. Torres , T. M. Dame , Seth W. Digel

We study the high latitude (|b|>10) diffuse gamma-ray emission in the Galaxy in light of the recently published data from the Fermi collaboration at energies between 100 MeV and 100 GeV. The unprecedented accuracy in these measurements…

High Energy Astrophysical Phenomena · Physics 2013-04-16 I. Cholis , M. Tavakoli , C. Evoli , L. Maccione , P. Ullio

Measurements of cosmic ray fluxes by the PAMELA and CREAM experiments show unexpected spectral features between 200 GeV and 100 TeV. They could be due to the presence of nearby and young cosmic ray sources. This can be studied in the myriad…

High Energy Astrophysical Phenomena · Physics 2012-10-15 G. Bernard , T. Delahaye , P. Salati , R. Taillet

This paper presents an introduction to the astrophysics of cosmic rays and diffuse gamma rays and discusses some of the puzzles that have emerged recently due to more precise data and improved propagation models: the excesses in Galactic…

Astrophysics · Physics 2008-11-26 I. V. Moskalenko

Cosmic rays, along with stellar radiation and magnetic fields, are known to make up a significant fraction of the energy density of galaxies such as the Milky Way. When cosmic rays interact in the interstellar medium, they produce gamma-ray…

We present the detection analysis of a diffuse molecular cloud at z$_{abs}$=2.4636 towards the quasar SDSS J1513+0352(z$_{em}\,\simeq$ 2.68) observed with the X-shooter spectrograph(VLT). We measure very high column densities of atomic and…

Cosmic Ray nuclei in the energy range 100 MeV/nuc - 100 GeV/nuc provide crucial information about the physical properties of the Galaxy. They can also be used to answer questions related to astroparticle physics. This paper reviews the…

Continuum gamma-ray emission produced by interactions of cosmic rays with interstellar matter and radiation fields is a probe of non-thermal particle populations in galaxies. After decades of continuous improvements in experimental…

High Energy Astrophysical Phenomena · Physics 2021-05-12 Luigi Tibaldo , Daniele Gaggero , Pierrick Martin

We analyzed the 2.6-mm CO and 21-cm HI lines toward the Magellanic superbubble 30 Doradus C, in order to reveal the associated molecular and atomic gas. We uncovered five molecular clouds in a velocity range from 251 to 276 km s$^{-1}$…

The spectral data on the diffuse Galactic gamma-rays, at medium and high latitudes (|b| > 10) and energies of 1-100 GeV, recently published by the Fermi Collaboration are used to produce a novel study on the gamma-ray emissivity in the…

High Energy Astrophysical Phenomena · Physics 2011-10-28 Maryam Tavakoli , Ilias Cholis , Carmelo Evoli , Piero Ullio

Observations of very-high-energy (VHE) gamma-ray emission from supernova remnants (SNR) established them as sources of accelerated particles up to energies of 100 TeV. The dominant process - leptonic or hadronic - responsible for the VHE…

High Energy Astrophysical Phenomena · Physics 2013-07-23 Stephanie Häffner , Ira Jung , Christian Stegmann

Various studies have implied the existence of a gaseous halo around the Galaxy extending out to 100 kpc. Galactic cosmic rays (CRs) that propagate to the halo, either by diffusion or by convection with the possibly existing large-scale…

High Energy Astrophysical Phenomena · Physics 2019-01-30 Ruo-Yu Liu , Huirong Yan , Xiang-Yu Wang , Shi Shao , Hui Li

We simulate the neutrino and $\gamma$-ray emissions of the Galaxy which are originated from the hadronic scattering of cosmic rays (CR) with the interstellar medium (ISM). Rather than assuming a uniform CR density, we estimate the spatial…

Astrophysics · Physics 2010-10-27 Carmelo Evoli , Dario Grasso , Luca Maccione

Recent direct measurements of Galactic cosmic ray spectra by balloon/space-borne detectors reveal spectral hardenings of all major nucleus species at rigidities of a few hundred GV. The all-sky diffuse gamma-ray emissions measured by the…

High Energy Astrophysical Phenomena · Physics 2018-03-21 Yi-Qing Guo , Qiang Yuan