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Related papers: Molecular Evolution in Collapsing Prestellar Cores

200 papers

Both analytic and numerical radiative transfer models applied to high spectral resolution CS and N2H+ data give insight into the evolutionary state of L1551 MC. This recently discovered pre-protostellar core in L1551 appears to be in the…

Astrophysics · Physics 2009-11-13 J. Swift , Wm. J. Welch , J. Di Francesco , I. Stojimirovic

The collapse of dense cores with different metallicities is studied by hydrodynamical calculations coupled with detailed chemical and radiative processes. For this purpose, we construct a simple chemical network with non-equilibrium…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Kazuyuki Omukai , Takashi Hosokawa , Naoki Yoshida

We present PrestaLine: Gorynych, a comprehensive numerical tool designed to model the dynamical, chemical, and spectral evolution of collapsing molecular cores from the prestellar phase to protostellar accretion. The code integrates three…

Astrophysics of Galaxies · Physics 2026-02-16 Olga Kochina , Dmitri Wiebe , Yaroslav Pavlyuchenkov , Maria S. Kirsanova

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

In this study, the main goal is to understand the molecular cloud core collapse through the stages of first and second hydrostatic core formation. We investigate the properties of Larson's first and second cores following the evolution of…

Solar and Stellar Astrophysics · Physics 2018-10-24 Asmita Bhandare , Rolf Kuiper , Thomas Henning , Christian Fendt , Gabriel-Dominique Marleau , Anders Kölligan

The current study was developed to provide a database of relatively simple numerical simulations of protostellar collapse, as a template library for observations of cores and very young protostars, and for researchers who wish to test their…

Solar and Stellar Astrophysics · Physics 2018-08-08 Neil Vaytet , Troels Haugbølle

Prestellar cores represent the initial conditions of star formation, but heavy molecules such as CO are strongly depleted in their cold, dense interiors, limiting the ability to probe core centers. Deuterated molecular ions therefore emerge…

In this study we investigate the formation and properties of prestellar and protostellar cores using hydrodynamic, self-gravitating Adaptive Mesh Refinement simulations, comparing the cases where turbulence is continually driven and where…

Astrophysics · Physics 2009-11-13 S. S. R. Offner , M. R. Krumholz , R. I. Klein , C. F. McKee

The evolution of star-forming core analogues undergoing inside-out collapse is studied with a multi-point chemodynamical model which self-consistently computes the abundance distribution of chemical species in the core. For several collapse…

Astrophysics · Physics 2008-07-27 Y. G. Tsamis , J. M. C. Rawlings , J. A. Yates , S. Viti

Prestellar cores are unique laboratories for studies of the chemical and physical conditions preceding star formation. We observed the prestellar core L1544 in the fundamental transition of ortho-H2D+ (1_1,0-1_1,1) at different positions…

Astrophysics · Physics 2009-11-11 C. Vastel , P. Caselli , C. Ceccarelli , T. G. Phillips , M. Wiedner , R. peng , M. Houde , C. Dominik

A solar-type system starts from an initial molecular core that acquires organic complexity as it evolves. The so-called prestellar cores that can be studied are rare, which has hampered our understanding of how organic chemistry sets in and…

We study the changes in physical and chemical conditions during the collapse of a pre--protostellar core, starting from initial conditions appropriate to a dense molecular cloud and proceeding to the ``completely depleted'' limit. We follow…

Astrophysics · Physics 2009-11-10 D. R. Flower , G. Pineau des Forets C. M. Walmsley

We report the detection of D2CO in a sample of starless dense cores, in which we previously measured the degree of CO depletion. The deuterium fractionation is found extremely high, [D2CO]/[H2CO] ~ 1-10 %, similar to that reported in…

We study the formation and evolution of several molecules in a collapsing interstellar cloud using a reasonably large reaction network containing more then four hundred atomic and molecular species. We employ a time dependent, spherically…

Astrophysics · Physics 2009-06-30 Ankan Das , Sandip Kumar Chakrabarti , Kinsuk Acharyya , Sonali Chakrabarti

We investigate the time evolution of dense cores identified in molecular cloud simulations using dendrograms, which are a common tool to identify hierarchical structure in simulations and observations of star formation. We develop an…

Astrophysics of Galaxies · Physics 2020-08-12 Rachel A. Smullen , Kaitlin M. Kratter , Stella S. R. Offner , Aaron T. Lee , Hope How-Huan Chen

Dense cloud cores present chemical differentiation due to the different distribution of C-bearing and N-bearing molecules, the latter being less affected by freeze-out onto dust grains. In this letter we show that two C-bearing molecules,…

Astrophysics of Galaxies · Physics 2016-08-17 Silvia Spezzano , Luca Bizzocchi , Paola Caselli , Jorma Harju , Sandra Brünken

Pre-stellar cores represent a critical evolutionary phase in low-mass star formation. We aim to unveil the detailed thermal structure and density distribution of three early-stage cores, starless core L1517B, and prestellar core L694-2 and…

Astrophysics of Galaxies · Physics 2023-08-25 Yuxin Lin , Silvia Spezzano , Jaime E. Pineda , Jorma Harju , Anika Schmiedeke , Sihan Jiao , Hauyu Baobab Liu , Paola Caselli

We have performed a pointed survey of N2D+ 2-1 and N2D+ 3-2 emission toward 64 N2H+-bright starless and protostellar cores in the Perseus molecular cloud using the Arizona Radio Observatory Submillimeter Telescope and Kitt Peak 12 m…

Solar and Stellar Astrophysics · Physics 2015-06-12 Rachel Friesen , Helen Kirk , Yancy Shirley

We present a catalogue of molecular cloud cores drawn from high latitude, medium opacity clouds, using the all-sky IRAS Sky Survey Atlas (ISSA) images at 60 and 100~$\mu$m. The typical column densities of the cores are $ N(H_2)\sim 3.8…

Astrophysics · Physics 2009-10-31 N. E. Jessop , D. Ward-Thompson

The deuterium fractionation in starless cores gives us a clue to estimate their lifetime scales, thus allowing us to distinguish between different dynamical theories of core formation. Cores also seem to be subject to a differential N2 and…

Astrophysics of Galaxies · Physics 2020-04-08 Sheng-Jun Lin , Laurent Pagani , Shih-Ping Lai , Charlène Lefèvre , François Lique