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Related papers: Cosmic-ray heating of molecular cloud cores

200 papers

Icy grains in the interstellar medium and star-formation regions consist of a variety of materials. Such composite grains interact differently with cosmic-ray (CR) particles compared to simple single-material grains. We aim to calculate the…

Astrophysics of Galaxies · Physics 2022-09-21 Juris Kalvans , Juris Roberts Kalnin

The interstellar medium (ISM) of galaxies very often contains a gas component that reaches the temperature of several million degrees, whose physical and chemical properties can be investigated through imaging and spectroscopy in the…

Astrophysics of Galaxies · Physics 2023-04-05 Emanuele Nardini , Dong-Woo Kim , Silvia Pellegrini

The mass of prestellar cores is an essential ingredient to understand the onset of star formation in the core. The low level of emission from cold dust may keep parts of it hidden from observation. We aim to determine the fraction of core…

Astrophysics of Galaxies · Physics 2016-09-21 Juergen Steinacker , Hendrik Linz , Henrik Beuther , Thomas Henning , Aurore Bacmann

Cosmic rays (CRs) are the primary driver of ionization in star forming molecular clouds (MCs). Despite their potential impacts on gas dynamics and chemistry, no simulations of star cluster formation following the creation of individual…

Astrophysics of Galaxies · Physics 2024-07-26 Margot Fitz Axen , Stella Offner , Phillip F. Hopkins , Mark R. Krumholz , Michael Y. Grudic

To evaluate the effect of turbulent heating in the thermal balance of interstellar clouds, we develop an extension of the log-Poisson intermittency model to supersonic turbulence. The model depends on a parameter, d, interpreted as the…

Astrophysics · Physics 2011-02-11 Liubin Pan , Paolo Padoan

Cosmic rays are charged energetic particles that permeate the interstellar medium. Their sizeable energy share and penetration power makes them essential players in the dynamical and chemical processes that rule Galactic evolution, such as…

High Energy Astrophysical Phenomena · Physics 2026-03-17 Giada Peron , Sarah Recchia , Stefano Menchiari , Alexandre Marcowith , Andrei Bykov , Martin Pohl , Elena Amato

The Galactic center region near l$\approx0.2^0$ hosts a mixture of nonthermal linear filaments and thermal radio continuum features associated with the radio Arc. Chandra observations of this region reveal an X-ray filament and diffuse…

Astrophysics · Physics 2009-11-07 F. Yusef-Zadeh , C. Law , M. Wardle

Molecular ionization in the Central Molecular Zone of our galaxy is enhanced over the typical galactic value by an order of magnitude or more. This cannot be easily explained for dense Galactic Center molecular complexes in the absence of…

High Energy Astrophysical Phenomena · Physics 2018-12-12 Joseph Silk

We reported the gamma-ray observation towards the giant molecular cloud Polaris Flare. Together with the dust column density map, we derived the cosmic ray density and spectrum in this cloud. Compared with the CR measured locally, the CR…

High Energy Astrophysical Phenomena · Physics 2021-12-08 Zhi-wei Cui , Rui-zhi Yang , Bing Liu

The galactic diffuse $\gamma$-ray emission, as seen by Fermi Large Area Telescope (LAT), shows a sharp peak in the region around 4 kpc from the Galactic center, which can be interpreted either as due to an enhanced density of cosmic-ray…

High Energy Astrophysical Phenomena · Physics 2021-03-23 Giada Peron , Felix Aharonian , Sabrina Casanova , Ruizhi Yang , Roberta Zanin

Molecular clouds act as targets for cosmic rays (CR), revealing their presence through either gamma-ray emission due to proton-proton interactions, and/or through the ionization level in the cloud, produced by the CR flux. The ionization…

High Energy Astrophysical Phenomena · Physics 2015-07-21 Julian Krause , Giovanni Morlino , Stefano Gabici

We assess the ionising effect of low energy protostellar cosmic rays in protoplanetary disks around a young solar mass star for a wide range of disk parameters. We assume a source of low energy cosmic rays located close to the young star…

Solar and Stellar Astrophysics · Physics 2020-01-08 D. Rodgers-Lee , A. M. Taylor , T. P. Downes , T. P. Ray

Cooling and heating functions of cosmic gas are a crucial ingredient for any study of gas dynamics and thermodynamics in the interstellar and intergalactic medium. As such, they have been studied extensively in the past under the assumption…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Nickolay Y. Gnedin , Nicholas Hollon

Cosmic rays provide an important source for free electrons in the Earth's atmosphere and also in dense interstellar regions where they produce a prevailing background ionization. We utilize a Monte Carlo cosmic ray transport model for…

Solar and Stellar Astrophysics · Physics 2015-06-16 Paul Rimmer , Christiane Helling

When the neutral interstellar medium is exposed to EUV and soft X ray radiation, the argon atoms in it are far more susceptible to being ionized than the hydrogen atoms. We make use of this fact to determine the level of ionization in the…

Astrophysics of Galaxies · Physics 2013-01-29 Edward B. Jenkins

A flux of cosmic rays (CRs) propagating through a diffuse ionized gas can excite MHD waves, thus generating magnetic disturbances. We propose a generic model of CR penetration into molecular clouds through their diffuse envelopes, and…

High Energy Astrophysical Phenomena · Physics 2018-03-14 A. V. Ivlev , V. A. Dogiel , D. O. Chernyshov , P. Caselli , C. -M. Ko , K. S. Cheng

In the interstellar medium, cosmic rays (CRs) generate a field of ultraviolet (UV) photons via the excitation and subsequent radiative decay of $\rm H_2$ molecules. This UV field is a major agent of ionization and dissociation in the inner…

Astrophysics of Galaxies · Physics 2026-01-15 O. Sipilä , P. Caselli , M. Padovani , D. Galli , T. Grassi , H. R. Hrodmarsson , S. S. Jensen , E. Roueff

Molecular clouds are a fundamental ingredient of galaxies: they are the channels that transform the diffuse gas into stars. The detailed process of how they do it is not completely understood. We review the current knowledge of molecular…

The local cosmic-ray (CR) spectra are calculated for typical characteristic regions of a cold dense molecular cloud, to investigate two so far neglected mechanisms of dust charging: collection of suprathermal CR electrons and protons by…

Astrophysics of Galaxies · Physics 2015-11-05 Alexei Ivlev , Marco Padovani , Daniele Galli , Paola Caselli

Low-energy cosmic rays, in particular protons with energies below 1 GeV, are significant drivers of the thermochemistry of molecular clouds. However, these cosmic rays are also greatly impacted by energy losses and magnetic field transport…

High Energy Astrophysical Phenomena · Physics 2021-09-08 Brandt A. L. Gaches , Stefanie Walch , Alex Lazarian