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Related papers: Chemical Models of Collapsing Envelopes

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This paper will review the basic concepts of gas-phase and grain surface chemistry of dense molecular clouds, where low mass and high mass stars form. The chemistry of cold pre-stellar cloud cores, where molecular freeze-out and deuterium…

Astrophysics · Physics 2017-03-08 Paola Caselli

The predictions of the multiple burst accretion model of chemical evolution are compared to the observations of the stellar masses and metallicities of star-forming galaxies. With the addition of one parameter, the model can account for the…

Astrophysics of Galaxies · Physics 2016-04-27 F. D. A. Hartwick

We are carrying out a physical and chemical study of the protostellar envelopes in a representative sample of IM Class 0 protostars. In our first paper (Crimier et al. 2010), we determined the physical structure (density-temperature radial…

Context. The recent detection of nitrogen-enhanced, metal-poor galaxies at high redshift by the James Webb Space Telescope has sparked renewed interest in exploring the chemical evolution of carbon, nitrogen, and oxygen (the CNO elements)…

Sun like stars are born from the collapse of fragment of molecular clouds. During the first embedded phase (the so called class 0/1), the protostar is surrounded by a collapsing envelope, whose physical and chemical structure would set up…

Astrophysics · Physics 2007-05-23 S. Maret , C. Ceccarelli , E. Caux , A. G. G. M. Tielens , A. Castets

Protoplanetary discs are dynamic environments where the interplay between chemical processes and mass transport shapes the composition of gas and dust available for planet formation. We investigate the combined effects of volatile chemistry…

Observations have revealed that the elemental abundances of carbon and oxygen in the warm molecular layers of some protoplanetary disks are depleted compared to those is the interstellar medium by a factor of ~10-100. Meanwhile, little is…

Earth and Planetary Astrophysics · Physics 2022-10-26 Kenji Furuya , Seokho Lee , Hideko Nomura

We present the first gas-grain astrochemical model of the NGC 2264 CMM3 protostellar core. The chemical evolution of the core is affected by changing its physical parameters such as the total density and the amount of gas-depletion onto…

Astrophysics of Galaxies · Physics 2017-03-21 Zainab Awad , Osama M. Shalabeia

Molecular oxygen has been the subject of many observational searches as chemical models predicted it to be a reservoir of oxygen. Although it has been detected in two regions of the interstellar medium, its rarity is a challenge for…

Astrophysics of Galaxies · Physics 2019-06-04 V. Wakelam , M. Ruaud , P. Gratier , I. A. Bonnell

Stars in galaxies form in giant molecular clouds that coalesce when the atomic hydrogen is converted into molecules. There are currently two dominant models for what property of the galactic disk determines its molecular fraction: either…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Michele Fumagalli , Mark R. Krumholz , Leslie K. Hunt

Protoplanetary disks are the target of many chemical studies (both observational and theoretical) as they contain the building material for planets. Their large vertical and radial gradients in density and temperature make them challenging…

Astrophysics of Galaxies · Physics 2016-10-07 V. Wakelam , M. Ruaud , F. Hersant , A. Dutrey , D. Semenov , L. Majumdar , S. Guilloteau

We review general characteristics of massive stars, present the main observable constraints that stellar models should reproduce. We discuss the impact of massive star nucleosynthesis on the early phases of the chemical evolution of the…

The study of protostellar collapse or infall has proven unusually difficult and controversial. Some historical context will be provided, against which recent advances can be measured. We now have a substantial number of objects with…

Astrophysics · Physics 2007-05-23 N. J. Evans

We investigate chemistry in the compression layer behind the interstellar shock waves, where molecular cloud formation starts. We perform three-dimensional magnetohydrodynamics simulations of converging flows of atomic gas with shock…

Astrophysics of Galaxies · Physics 2024-11-20 Yuto Komichi , Yuri Aikawa , Kazunari Iwasaki , Kenji Furuya

We examined the gravitational contraction of isothermal molecular cloud cores with slow rotation by means of two-dimensional numerical simulations. Applying a sink-cell method, we followed the evolution of the cloud cores up to the stages…

Astrophysics · Physics 2009-10-31 Fumitaka Nakamura

The kinematic and radiative power of molecular jets is expected to change as a protostar undergoes permanent or episodal changes in the rate at which it accretes. We study here the consequences of evolving jet power on the spatial and…

Astrophysics · Physics 2009-11-07 Alexander Rosen , Michael D. Smith

Context. Interstellar surface chemistry is a complex process that occurs in icy layers accumulated onto grains of different sizes. Efficiency of surface processes often depends on the immediate environment of adsorbed molecules. Aims. We…

Astrophysics of Galaxies · Physics 2024-07-31 Juris Kalvāns , Aija Kalniņa , Kristaps Veitners

Sun like stars are born from the collapse of fragment of molecular clouds. During the first embedded phase (the so called class 0/1), the protostar is surrounded by a collapsing envelope, whose physical and chemical structure would set up…

Astrophysics · Physics 2009-11-07 S. Maret , C. Ceccarelli , E. Caux , A. G. G. M. Tielens , A. Castets

The composition of gas and solids in protoplanetary discs sets the composition of planets that form out of them. Recent chemical models have shown that the composition of gas and dust in discs evolves on Myr time-scales, with volatile…

Earth and Planetary Astrophysics · Physics 2019-05-31 Richard A. Booth , John D. Ilee

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…

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