Astrochemistry: Synthesis and modelling
Valentine Wakelam,Herma M. Cuppen,Eric Herbst +2 more
- 01 Jan 2013
- pp 115-143
TL;DR: In this paper, the authors discuss models that astrochemists have developed to study the chemical composition of the interstellar medium, which aim at computing the evolution of the chemical compositions of a mixture of gas and dust under astrophysical conditions.
read more
Abstract: We discuss models that astrochemists have developed to study the chemical composition of the interstellar medium. These models aim at computing the evolution of the chemical composition of a mixture of gas and dust under astrophysical conditions. These conditions, as well as the geometry and the physical dynamics, have to be adapted to the objects being studied because different classes of objects have very different characteristics (temperatures, densities, UV radiation fields, geometry, history etc); e.g., proto-planetary disks do not have the same characteristics as proto-stellar envelopes. Chemical models are being improved continually thanks to comparisons with observations but also thanks to laboratory and theoretical work in which the individual processes are studied.
read more
Chat with Paper
AI Agents for this Paper
Find similar papers on Google Scholar, PubMed and Arxiv
Write a critical review of this paper
Analyze citations of this paper to find unaddressed research gaps
Figures
Fig. 4.5 Possible distributions (lognormal or loguniform) of the rate coefficients randomly varied within a factor F0. 
Fig 4.10 Gas-phase CN and O2 abundances predicted by a gas-grain chemical model under dense cloud conditions (same as Fig. 4.7) and a C/O elemental ratio of 1.2, as a function of time. Black and purple curves were obtained for a C + CN rate coefficient of 3x10-10 cm3 s-1 and 2x10-11 cm3 s-1 at 10 K respectively. 
Fig. 4.7 CO, O2 and H2O abundance predicted by a gas-phase model under dense cloud conditions. ![Fig. 4.2 Temperature and density of H2 profiles in the envelope of the low mass proto-star IRAS 16293-2422 based on multi-wavelength observations from Crimier et al. [19].](/figures/figure4-2-1-5fxmxsy31zlu.png)
Fig. 4.2 Temperature and density of H2 profiles in the envelope of the low mass proto-star IRAS 16293-2422 based on multi-wavelength observations from Crimier et al. [19]. 
Fig. 4.8 CO, O2 and H2O abundances predicted by a gas-phase model under dense cloud conditions (same as Fig. 4.7) and by a gas-phase model including sticking and evaporation of species from grain surfaces (orange lines). 
Fig. 4.3 Representation of a circumstellar envelope (courtesy of Marcelino Agundez).
![Fig. 4.2 Temperature and density of H2 profiles in the envelope of the low mass proto-star IRAS 16293-2422 based on multi-wavelength observations from Crimier et al. [19].](/figures/figure4-2-1-5fxmxsy31zlu.webp)
Citations
Chemistry of Dark Clouds: Databases, Networks, and Models
TL;DR: In this paper, the authors assess the state of the art concerning the chemical modeling of dark clouds, the initial step for the formation of stars and disks, and assess the current state-of-the-art in the field of astrophysics.
246
H2 formation on interstellar dust grains: The viewpoints of theory, experiments, models and observations
Valentine Wakelam,Emeric Bron,Emeric Bron,Stéphanie Cazaux,Stéphanie Cazaux,François Dulieu,Cecile Gry,Pierre Guillard,E. Habart,Liv Hornekær,Sabine Morisset,Gunnar Nyman,Valerio Pirronello,Stephen D. Price,Valeska Valdivia,Gianfranco Vidali,Naoki Watanabe +16 more
TL;DR: In this paper, the authors present what they think we know about the H2 formation in a variety of interstellar environments, in the perspective of the probable revolution brought by the future satellite JWST.
225
An Infrared Spectroscopic Study Toward the Formation of Alkylphosphonic Acids and Their Precursors in Extraterrestrial Environments.
TL;DR: The first study and results on the possible synthesis of alkylphosphonic acids produced from phosphine-mixed ices under interstellar conditions are presented, suggesting that this class of molecules can be formed in interstellar ices.
Nautilus multi-grain model: Importance of cosmic-ray-induced desorption in determining the chemical abundances in the ISM
Wasim Iqbal,Valentine Wakelam +1 more
TL;DR: In this article, the impact on the abundances of many species observed in the cold cores by considering several grain sizes in the Nautilus multi-grain model has been studied, and the differences between the MRN and the WD models are crucial for better fitting the observed abundances in different regions in the ISM.
22
The Impact of Protostellar Feedback on Astrochemistry
Brandt A.L. Gaches,Stella S. S. Offner,Thomas G. Bisbas +2 more
- 01 Jan 2019
TL;DR: The impact of PROTOSTELLAR FEEDBACK on ASTROCHEMISTRY is discussed in this paper, where the authors discuss the impact of the feedback on ASTrochEMisTRY.
17
References
Microscopic simulation of methanol and formaldehyde ice formation in cold dense cores
TL;DR: In this article, a model was developed to simulate CO hydrogenation via H atoms on interstellar ice surfaces, the most important interstellar route to H2CO and CH3OH, under laboratory conditions.
Herschel observations of EXtra-Ordinary Sources: the present and future of spectral surveys with Herschel/HIFI
E. A. Bergin,Thomas G. Phillips,C. Comito,Nathan R. Crockett,D. C. Lis,Peter Schilke,S. Wang,T. A. Bell,G. A. Blake,Bruce Bumble,Emmanuel Caux,S. Cabrit,Cecilia Ceccarelli,José Cernicharo,Fabien Daniel,Th. de Graauw,Marie-Lise Dubernet,Martin Emprechtinger,P. J. Encrenaz,E. Falgarone,Maryvonne Gerin,Thomas F. Giesen,J. R. Goicoechea,P. F. Goldsmith,H. Gupta,Paul Hartogh,Frank Helmich,Eric Herbst,C. Joblin,D. Johnstone,J. Kawamura,W. D. Langer,William B. Latter,S. D. Lord,Sébastien Maret,Pierrick Martin,Gary J. Melnick,Karl M. Menten,Patrick W. Morris,Holger S. P. Müller,J. A. Murphy,David A. Neufeld,Volker Ossenkopf,Laurent Pagani,J. C. Pearson,M. Perault,Rene Plume,Pieter R. Roelfsema,S.-L. Qin,M. Salez,Stephan Schlemmer,J. Stutzki,Aggm Tielens,Neil Trappe,F. F. S. van der Tak,Charlotte Vastel,H. W. Yorke,Shanshan Yu,Jonas Zmuidzinas +58 more
TL;DR: In this paper, the spectral properties of the Orion hot core were investigated using the Herschel GT key program and the HIFI spectra of Orion KL between 480 and 560 GHz and from 1.06 to 1.115 THz.
Oxygen depletion in dense molecular clouds: a clue to a low O-2 abundance?
U. Hincelin,U. Hincelin,Valentine Wakelam,Valentine Wakelam,F. Hersant,F. Hersant,Stéphane Guilloteau,Stéphane Guilloteau,Jean-Christophe Loison,Jean-Christophe Loison,Pascal Honvault,Pascal Honvault,Jürgen Troe +12 more
TL;DR: In this article, the authors used the gas-grain code Nautilus with an up-to-date gas-phase network to study the sensitivity of the molecular oxygen abundance to the oxygen elemental abundance.
154
Ultraviolet photodesorption from water ice
TL;DR: The absolute desorption yield of low temperature (35-100 K) water ice under irradiation with Lyman-α (121.6 nm) photons was measured in this paper.
153
Master Equation for Hydrogen Recombination on Grain Surfaces
TL;DR: In this article, a master equation that takes into account both the discrete nature of the H atoms and the fluctuations in the number of atoms on a grain is introduced to calculate the hydrogen recombination rate on microscopic grains, as a function of grain size and temperature.