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Related papers: UCLCHEM: A Gas-Grain Chemical Code

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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

The gravitational collapse of a spherical cloud core is investigated by numerical calculations. The initial conditions of the core lie close to the critical Bonnor-Ebert sphere with a central density of \sim 10^4 cm^{-3} in one model…

Astrophysics · Physics 2009-11-10 Yuri Aikawa , Eric Herbst , Helen Roberts , Paola Caselli

Atoms and molecules, and in particular CO, are important coolants during the evolution of interstellar star-forming gas clouds. The presence of dust grains, which allow many chemical reactions to occur on their surfaces, strongly impacts…

Solar and Stellar Astrophysics · Physics 2015-06-17 S. Hocuk , S. Cazaux , M. Spaans

We quantify if the chemical abundance gradients given by a dynamical model of core collapse including time-dependent changes in density and temperature differ greatly from abundances derived from static models, where the density and…

Astrophysics of Galaxies · Physics 2018-07-18 O. Sipilä , P. Caselli

The study of the chemical composition of star-forming regions is key to understanding the chemical ingredients available during the formation of planetary systems. Because the chemical inventory of interstellar dust grains in prestellar…

AIM: We have recently developed a microscopic Monte Carlo approach to study surface chemistry on interstellar grains and the morphology of ice mantles. The method is designed to eliminate the problems inherent in the rate-equation formalism…

Astrophysics · Physics 2009-11-13 Q. Chang , H. M. Cuppen , E. Herbst

For the first time, we report a unified microscopic-macroscopic Monte Carlo simulation of gas-grain chemistry in cold interstellar clouds in which both the gas-phase and the grain surface chemistry are simulated by a stochastic technique.…

Astrophysics of Galaxies · Physics 2015-06-11 Qiang Chang , Eric Herbst

The physical and chemical conditions in Class 0/I protostars are fundamental in unlocking the protostellar accretion process and its impact on planet formation. The aim is to determine which physical components are traced by different…

Hot corino chemistry and warm carbon chain chemistry (WCCC) are driven by gas-grain interactions in star-forming cores: radical-radical recombination reactions to form complex organic molecules (COMs) in the ice mantle, sublimation of…

Solar and Stellar Astrophysics · Physics 2020-07-15 Yuri Aikawa , Kenji Furuya , Satoshi Yamamoto , Nami Sakai

Context: Complex molecules such as ethanol and dimethyl ether have been observed in a number of hot molecular cores and hot corinos. Attempts to model the molecular formation process using gas phase only models have so far been…

Astrophysics of Galaxies · Physics 2015-05-18 P. Hall , T. J. Millar

The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemical properties of these sources and help us estimate their evolutionary stages. We report line detections within the 3 mm band using…

Astrophysics of Galaxies · Physics 2025-04-09 Yang Yang , Xi Chen , ZhiBo Jiang , Zhiwei Chen , Shuling Yu , Jun Li

We study the gravitational collapse of prestellar sources and the associated evolution of their chemical composition. We use the University of Grenoble Alpes Astrochemical Network (UGAN), which includes reactions involving the different…

Astrophysics of Galaxies · Physics 2018-04-25 P. Hily-Blant , A. Faure , C. Rist , G. Pineau des Foreêts , D. R. Flower

The quantity of NH3 produced on grain surfaces in the prestellar core is thought to be one of the determining factors regarding the chemical complexity achievable at later stages of stellar birth. In order to investigate how this quantity…

Astrophysics of Galaxies · Physics 2020-12-09 Azrael A. von Procházka , T. J. Millar

A scattering model is developed for ultracold molecular collisions, which allows inelastic processes, chemical reactions, and complex formation to be treated in a unified way. All these scattering processes and various combinations of them…

Atomic Physics · Physics 2020-09-23 James F. E. Croft , John L. Bohn , Goulven Quéméner

Because of the very peculiar conditions of chemistry in many astrophysical gases (low densities, mostly low temperatures, kinetics-dominated chemical evolution), great efforts have been devoted to study molecular signatures and chemical…

The observed gas-phase molecular inventory of hot cores is believed to be significantly impacted by the products of chemistry in interstellar ices. In this study, we report the construction of a full macroscopic Monte Carlo model of both…

Astrophysics of Galaxies · Physics 2015-06-12 A. I. Vasyunin , E. Herbst

Bipolar outflows constitute some of the best laboratories to study shock chemistry in the interstellar medium. A number of molecular species have their abundance enhanced by several orders of magnitude in the outflow gas, likely as a…

Astrophysics of Galaxies · Physics 2015-06-04 Mario Tafalla , Rafael Bachiller

Dust plays a key role in the evolution of the ISM and its correct modelling in numerical simulations is therefore fundamental. We present a new and self-consistent model that treats grain thermal coupling with the gas, radiation balance,…

Astrophysics of Galaxies · Physics 2017-01-25 T. Grassi , S. Bovino , T. Haugboelle , D. R. G. Schleicher

The circumnuclear disk (CND) of the Galactic Center is exposed to many energetic phenomena coming from the supermassive black hole Sgr A* and stellar activities. These energetic activities can affect the chemical composition in the CND by…

With the launch of the James Webb Space Telescope, we are firmly in the era of exoplanet atmosphere characterization. Understanding exoplanet spectra requires atmospheric chemical and climate models that span the diversity of planetary…