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(Abridged) We aim to enlarge the number of known hot corinos and carry out a first comparative study with hot cores. The ultimate goal is to understand whether complex organic molecules form in the gas phase or on grain surfaces, and what…

Context. Interstellar dust particles, which represent 1% of the total mass, are recognized to be very powerful interstellar catalysts in star-forming regions. The presence of dust can have a strong impact on the chemical composition of…

Solar and Stellar Astrophysics · Physics 2015-12-23 S. Cazaux , M. Minissale , F. Dulieu , S. Hocuk

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

We investigate the impact of cosmic rays (CRs) on galactic outflows from a multi-phase interstellar medium with solar neighbourhood conditions. The three-dimensional magneto-hydrodynamical simulations include CRs as a relativistic fluid in…

Astrophysics of Galaxies · Physics 2018-07-11 Philipp Girichidis , Thorsten Naab , Michał Hanasz , Stefanie Walch

Galactic cosmic-ray source compositions, (Z/H)GCRS from H to Pb and ~10^8 - 10^14 eV, differ from solar-local interstellar, (Z/H)SS or (Z/H)ISM by ~20-200x. Both are mostly just mixes of core collapse (CCSN) and thermonuclear (SN Ia)…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Richard E. Lingenfelter

We have investigated the role of molecular anion chemistry in pseudo-time dependent chemical models of dark clouds. With oxygen-rich elemental abundances, the addition of anions results in a slight improvement in the overall agreement…

Astrophysics of Galaxies · Physics 2009-07-22 Catherine Walsh , Nanase Harada , Eric Herbst , T. J. Millar

We use hydrodynamical simulations of two Milky Way-mass galaxies to demonstrate the impact of cosmic-ray pressure on the kinematics of cool and warm circumgalactic gas. Consistent with previous studies, we find that cosmic-ray pressure can…

Advanced telescopes, such as ALMA and JWST, are likely to show that the chemical universe may be even more complex than currently observed, requiring astrochemical modelers to improve their models to account for the impact of new data.…

Astrophysics of Galaxies · Physics 2017-08-07 E M Penteado , C Walsh , H M Cuppen

Previous work by various authors has suggested that the detection by Herschel/HIFI of nitrogen hydrides along the low density lines of sight towards G10.6-0.4 (W31C) cannot be accounted for by gas-phase chemical models. In this paper we…

Astrophysics of Galaxies · Physics 2017-03-16 Zainab Awad , Serena Viti , David A. Williams

The study of the chemical evolution of glycine in the interstellar medium is one of challenging topics in astrochemistry. Here, we present the chemical modeling of glycine in hot cores using the state-of-the-art three-phase chemical model…

Astrophysics of Galaxies · Physics 2018-08-15 Taiki Suzuki , Liton Majumdar , Masatoshi Ohishi , Masao Saito , Tomoya Hirota , Valentine Wakelam

Gas-phase complex organic molecules have been detected toward a range of high- and low-mass star-forming regions at abundances which cannot be explained by any known gas-phase chemistry. Recent laboratory experiments show that UV…

Astrophysics of Galaxies · Physics 2015-05-18 Karin I. Oberg , Sandrine Bottinelli , Jes K. Jorgensen , Ewine F. van Dishoeck

Freeze-out of the gas phase elements onto cold grains in dense interstellar and circumstellar media builds up ice mantles consisting of molecules that are mostly formed in situ (H2O, NH3, CO2, CO, CH3OH, and more). This review summarizes…

Astrophysics of Galaxies · Physics 2015-09-23 Adwin Boogert , Perry Gerakines , Douglas Whittet

The recent unexpected detection of terrestrial complex organic molecules in the cold (~ 10 K) gas has cast doubts on the commonly accepted formation mechanisms of these species. Standard gas-phase mechanisms are inefficient and tend to…

Astrophysics of Galaxies · Physics 2016-03-02 Aurore Bacmann , Alexandre Faure

Molecular line observations may serve as diagnostics of the degree to which the number density of cosmic ray protons, having energies of 10s to 100s of MeVs each, is enhanced in starburst galaxies and galaxies with active nuclei. Results,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 E. Bayet , D. A. William , T. W. Hartquist , S. Viti

Cosmic rays (CRs) can significantly impact dense molecular clouds in galaxies, heating the interstellar medium (ISM) and altering its chemistry, ionization, and thermal properties. Their influence is particularly relevant in environments…

Astrophysics of Galaxies · Physics 2026-05-20 E. Koutsoumpou , J. A. Fernández-Ontiveros , K. M. Dasyra , L. Spinoglio

We examine in detail the recent proposal that extreme Cosmic-Ray-Dominated-Regions (CRDRs) characterize the ISM of galaxies during events of high-density star formation, fundamentally altering its initial conditions (Papadopoulos 2010).…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Padeli P. Papadopoulos , Wing-Fai Thi , Francesco Miniati , Serena Viti

Understanding the processes occurring in the nuclear disk of our Galaxy is interesting in its own right, as part of the Milky Way Galaxy, but also because it is the closest galactic nucleus. It has been more than two decades since it was…

Astrophysics · Physics 2009-11-13 F. Yusef-Zadeh , M. Wardle , S. Roy

We have developed a high resolution combined physical and chemical model of a protoplanetary disk surrounding a typical T Tauri star. Our aims were to use our model to calculate the chemical structure of disks on small scales…

Astrophysics of Galaxies · Physics 2015-05-19 Catherine Walsh , T. J. Millar , Hideko Nomura

We first present chemodynamical simulations to investigate how stellar winds of massive stars influence early dynamical and chemical evolution of forming globular clusters (GCs). In our numerical models, GCs form in turbulent,high-density…

Astrophysics · Physics 2009-06-23 Kenji Bekki , Masashi Chiba

Context: Chemical models of dense cloud cores often utilize the so-called pseudo-time-dependent approximation, in which the physical conditions are held fixed and uniform as the chemistry occurs. In this approximation, the initial…

Solar and Stellar Astrophysics · Physics 2015-05-18 G. E. Hassel , E. Herbst , E. A. Bergin
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