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Related papers: Cold Clouds as Cosmic-Ray Detectors

200 papers

Cosmic rays (CRs) are a plausible mechanism for launching winds of cool material from the discs of star-forming galaxies. However, there is no consensus on what types of galaxies likely host CR-driven winds, or what role these winds might…

Astrophysics of Galaxies · Physics 2021-03-03 Roland M. Crocker , Mark R. Krumholz , Todd A. Thompson

We study the capability of low-energy cosmic rays (CR) to penetrate into diffuse clouds when they move from the hot ionized plasma to a cool cloud embedded in that plasma. The spectrum of CR inside a cloud can be remarkably different from…

High Energy Astrophysical Phenomena · Physics 2014-10-30 Giovanni Morlino , Stefano Gabici

Context. Cosmic rays (CRs) play an important role in the chemistry and dynamics of the interstellar medium. In dense environments, they represent the main ionising agent, driving the rich chemistry of molecular ions and determining the…

Astrophysics of Galaxies · Physics 2021-12-11 Elena Redaelli , Olli Sipilä , Marco Padovani , Paola Caselli , Daniele Galli , Alexei V. Ivlev

The cosmic ray ionization rate (CRIR) is a key parameter in understanding the physical and chemical processes in the interstellar medium. Cosmic rays are a significant source of energy in star formation regions, which impacts the physical…

Cosmic rays (CRs) govern the energetics of present-day galaxies and might have also played a pivotal role during the Epoch of Reionization. In particular, energy deposition by low-energy ($E \lesssim 10$ MeV) CRs accelerated by the first…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-16 Natacha Leite , Carmelo Evoli , Marta D'Angelo , Benedetta Ciardi , Günter Sigl , Andrea Ferrara

Latest precise cosmic-ray (CR) measurements and present gamma-ray observations have started challenging our understanding of CR transport and interaction in the Galaxy. Moreover, because the density of CRs is similar to the density of the…

Non-thermal desorption of ices on interstellar grains is required to explain observations of molecules that are not synthesized efficiently in the gas phase in cold dense clouds. Perhaps the most important non-thermal desorption mechanism…

Astrophysics of Galaxies · Physics 2021-12-08 O. Sipilä , K. Silsbee , P. Caselli

Diffuse interstellar clouds show large abundances of H_3^+ which can be maintained only by a high ionization rate of H_2. Cosmic rays are the dominant ionization mechanism in this environment, so the large ionization rate implies a high…

High Energy Astrophysical Phenomena · Physics 2011-02-11 Nick Indriolo , Brian D. Fields , Benjamin J. McCall

Measurements of the low energy spectrum of Galactic Cosmic Rays (GCR) by detectors at or near the Earth are affected by Solar modulation. To overcome this difficulty, we consider nearby molecular clouds as GCR detectors outside the Solar…

High Energy Astrophysical Phenomena · Physics 2015-06-03 A. Neronov , D. V. Semikoz , A. M. Taylor

It is widely accepted that cosmic rays (CRs) up to at least PeV energies are Galactic in origin. Accelerated particles are injected into the interstellar medium where they propagate to the farthest reaches of the Milky Way, including a…

Galactic cosmic rays (CRs) play a crucial role in ionisation, dissociation, and excitation processes within dense cloud regions where UV radiation is absorbed by dust grains and gas species. CRs regulate the abundance of ions and radicals,…

The high-density star formation typical of the merger/starburst events that power the large IR luminosities of Ultra Luminous Infrared Galaxies (ULIRGs) (L_{IR}>10^{12}Lsol) throughout the Universe results to extraordinarily high cosmic ray…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Padelis P. Papadopoulos

We explore the effects of the expected higher cosmic ray (CR) ionization rates $\zeta_{\rm CR}$ on the abundances of carbon monoxide (CO), atomic carbon (C), and ionized carbon (C$^+$) in the H$_2$ clouds of star-forming galaxies. The study…

Cosmic rays (CR) propagate through the galactic scales down to the smaller scales at which stars form. CRs are close to energy equipartition with the other components of the interstellar medium and can provide a support against gravity if…

Astrophysics of Galaxies · Physics 2019-02-13 Benoît Commerçon , Alexandre Marcowith , Yohan Dubois

Cosmic rays (CRs) are an important energy source in the circum-galactic medium (CGM) that impact the multi-phase gas structure and dynamics. We perform two-dimensional CR-magnetohydrodynamic simulations to investigate the role of CRs in…

Astrophysics of Galaxies · Physics 2022-06-14 Xiaoshan Huang , Yan-fei Jiang , Shane W. Davis

Low-energy cosmic rays (LECRs) dominate the ionization in dense regions of molecular clouds in which other ionizers such as UV or X-ray photons are effectively shielded. Thus it was argued that the high ionization rate at the central…

High Energy Astrophysical Phenomena · Physics 2024-11-05 Bing Liu , Ruizhi Yang

Many massive galaxies at the centres of relaxed galaxy clusters and groups have vast reservoirs of cool (~10,000 K) and cold (~100 K) gas. In many low redshift brightest group and cluster galaxies this gas is lifted into the hot ISM in…

Cosmic-ray (CR) induced heating of whole interstellar grains is an important desorption mechanism for grain surface molecules in interstellar molecular clouds. This study aims to provide a detailed temperature spectra for such CR-induced…

Astrophysics of Galaxies · Physics 2018-11-14 Juris Kalvāns

Understanding how cosmic rays (CRs) propagate within the giant molecular clouds (GMCs) is critical for studying the dynamics and chemical processes inside the clouds. The flux of low-energy CRs inside the dense cores of GMCs strongly…

High Energy Astrophysical Phenomena · Physics 2024-12-03 Zhaodong Shi , Bing Liu , Rui-zhi Yang

The energy spectrum of electrons produced in molecular gas by interstellar cosmic rays (CRs) is rigorously calculated as a function of gas column density $N$ traversed by the CRs. This allows us to accurately compute the local value of the…

Astrophysics of Galaxies · Physics 2021-03-17 Alexei V. Ivlev , Kedron Silsbee , Marco Padovani , Daniele Galli