English
Related papers

Related papers: Chemical Evolution in VeLLOs

200 papers

Young stellar objects (YSOs) may undergo periods of active accretion (outbursts), during which the protostellar accretion rate is temporarily enhanced by a few orders of magnitude. Whether or not these accretion outburst YSOs possess…

A clear understanding of the chemical processing of matter, as it is transferred from a molecular cloud to a planetary system, depends heavily on knowledge of the physical conditions endured by gas and dust as these accrete onto a disk and…

Astrophysics · Physics 2007-05-23 David W. Koerner

We use high-resolution three-dimensional adaptive mesh refinement simulations to investigate the interaction of high-redshift galaxy outflows with low-mass virialized clouds of primordial composition. While atomic cooling allows star…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-24 William J Gray , Evan Scannapieco

The early universe hosted a large population of low-mass virialized "minihalos," that were not massive enough to form stars on their own. While most minihalos were photoevaporated by ionizing photons from star-forming galaxies, these…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 William J Gray , Evan Scannapieco

Understanding the chemical evolution in star-forming cores is a necessary pre-condition to correctly assess physical conditions when using molecular emission. We follow the evolution of chemistry and molecular line profiles through the…

Astrophysics · Physics 2009-11-10 Jeong-Eun Lee , Edwin A. Bergin , Neal J. Evans

Due to the recent dramatic technological advances, infrared interferometry can now be applied to new classes of objects, resulting in exciting new science prospects, for instance, in the area of high-mass star formation. Although…

Massive protostars grow and evolve under the effect of rapid accretion of circumstellar gas and dust, falling at high rates ($\ge 10^{-4}$-$10^{-3}\, \rm M_{\odot}\, \rm yr^{-1}$). This mass infall has been shown, both numerically and…

Solar and Stellar Astrophysics · Physics 2019-01-16 D. M. A. Meyer , L. Haemmerlé , E. I. Vorobyov

Complex organic molecules (COMs) are thought to be the precursors of pre-biotic molecules and are observed in many protostellar sources. For this paper we studied the formation of COMs during star formation and their evolution in the…

Jets and outflows are key components of low-mass star formation, regulating accretion and shaping the surrounding molecular clouds. These flows, traced by molecular species at (sub)millimeter wavelengths (e.g., CO, SiO, SO, H$_2$CO, and…

Astrophysics of Galaxies · Physics 2025-10-15 Somnath Dutta

The physical state of cold cloud clumps has a great impact on the process and efficiency of star formation and the masses of the forming stars inside these objects. The sub-millimetre survey of the Planck space observatory and the…

Astrophysics of Galaxies · Physics 2017-10-25 O. Fehér , M. Juvela , T. Lunttila , J. Montillaud , I. Ristorcelli , S. Zahorecz , L. V. Tóth

Young massive stars influence their surroundings from local to galactic scales, but the observational challenges associated with their distance and embedded nature has, until the recent decade, made high-resolution studies of these objects…

Solar and Stellar Astrophysics · Physics 2021-10-27 A. J. Frost , R. D. Oudmaijer , S. L. Lumsden , W-J de Wit

We present a survey toward 16 Low Luminosity Objects (LLOs with an internal luminosity, Lint, lower than 0.2 Lsun) with N2H+ (1-0), N2H+ (3-2), N2D+ (3-2), HCO+ (3-2) and HCN (3-2) using the Arizona Radio Observatory Kitt Peak 12m Telescope…

Astrophysics of Galaxies · Physics 2015-06-24 Tien-Hao Hsieh , Shih-Ping Lai , Arnaud Belloche , Friedrich Wyrowski , Chao-Ling Hung

Recent observations of the HDO/H$_2$O ratio toward protostars in isolated and clustered environments show an apparent dichotomy, where isolated sources show higher D/H ratios than clustered counterparts. Establishing which physical and…

Astrophysics of Galaxies · Physics 2021-05-12 S. S. Jensen , J. K. Jørgensen , K. Furuya , T. Haugbølle , Y. Aikawa

Very low-mass Class I protostars have been investigated very little thus far. Variability of these young stellar objects (YSOs) and whether or not they are capable of strong episodic accretion is also left relatively unstudied. We…

This paper explores the mapping between the observable properties of a stellar halo in phase- and abundance-space and the parent galaxy's accretion history in terms of the characteristic epoch of accretion and mass and orbits of progenitor…

Icy grain mantles are commonly observed through infrared spectroscopy toward dense clouds, cloud cores, protostellar envelopes and protoplanetary disks. Up to 80% of the available oxygen, carbon and nitrogen are found in such ices; the most…

[Abridged] Planets and their atmospheres are built from gas and solid material in protoplanetary disks. This solid material grows from smaller, micron-sized grains to larger sizes in the disks, during the process of planet formation. Our…

Earth and Planetary Astrophysics · Physics 2022-11-30 Christian Eistrup , L. Ilsedore Cleeves , Sebastiaan Krijt

Herbig-Haro objects (HHOs) are caused by outflows from young objects. Since the outflow relies on mass accretion from a circumstellar disk, it indicates ongoing growth. Recent results of infrared observations yielded evidence for disks…

Astrophysics · Physics 2008-11-26 Bringfried Stecklum , Helmut Meusinger , Dirk Froebrich

Submillimeter Array 1.3mm line and continuum observations toward the young massive star-forming region IRAS18182-1433 are presented. The data are complemented with short-spacing CO(2-1) observations and SiO(1-0) data from the VLA. Multiple…

Astrophysics · Physics 2009-11-11 H. Beuther , Q. Zhang , T. K. Sridharan , C. -F. Lee , L. A. Zapata

A model for massive stars is constructed by piecing together evolutionary algorithms for the protostellar structure, the environment, the inflow and the radiation feedback. We investigate specified accretion histories of constant,…

Astrophysics of Galaxies · Physics 2015-06-17 Michael D. Smith
‹ Prev 1 3 4 5 6 7 10 Next ›