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Related papers: Chemistry and Dynamics in Pre-Protostellar Cores

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Deuteration is a crucial tool to understand the complexity of interstellar chemical processes, especially when they involve the interplay of gas-phase and grain-surface chemistry. In the case of multiple deuteration, comparing observation…

Astrophysics of Galaxies · Physics 2022-05-25 S. Spezzano , O. Sipilä , P. Caselli , S. S. Jensen , S. Czakli , L. Bizzocchi , J. Chantzos , G. Esplugues , A. Fuente , F. Eisenhauer

C17O (J=2-1) observations have been carried out towards the pre-stellar core L1689B. By comparing the relative strengths of the hyperfine components of this line, the emission is shown to be optically thin. This allows accurate CO column…

Astrophysics · Physics 2009-11-07 M. P. Redman , J. M. C. Rawlings , D. J. Nutter , D. Ward-Thompson , D. A. Williams

In the centre of pre-stellar cores, deuterium fractionation is enhanced due to the low temperatures and high densities. Therefore, the chemistry of deuterated molecules can be used to study the earliest stages of star formation. We analyse…

Astrophysics of Galaxies · Physics 2023-08-16 K. Giers , S. Spezzano , P. Caselli , E. Wirström , O. Sipilä , J. E. Pineda , E. Redaelli , C. T. Bop , F. Lique

Seven isolated, nearby low-mass starless molecular cloud cores have been observed as part of the Herschel key program Earliest Phases of Star formation (EPoS). By applying a ray-tracing technique to the obtained continuum emission and…

In star-forming regions, molecular cloud history and dynamics set the trend in the chemical composition. Ice formation, in particular, is affected by the evolution of physical conditions, which can lead to different ice compositions within…

Astrophysics of Galaxies · Physics 2025-07-02 A. Taillard , V. Wakelam , P. Gratier , E. Dartois , M. Chabot , J. A. Noble , L. Chu

Understanding the depletion of heavy elements is a fundamental step towards determining the structure of pre-protostellar cores just prior to collapse. We study the dependence of the NO abundance on position in the pre-protostellar cores…

We have investigated the evolution and distribution of molecules in collapsing prestellar cores via numerical chemical models, adopting the Larson-Penston solution and its delayed analogues to study collapse. Molecular abundances and…

Astrophysics · Physics 2009-11-07 Y. Aikawa , N. Ohashi , S. Inutsuka , E. Herbst , S. Takakuwa

We present results from the Spitzer Space Telescope and molecular line observations of 9 species toward the dark cloud L43. The Spitzer images and molecular line maps suggest it has a starless core and a Class I protostar evolving in the…

Astrophysics of Galaxies · Physics 2014-11-20 Jo-Hsin Chen , Neal J. Evans , Jeong-Eun Lee , Tyler L. Bourke

The increased sensitivity and spectral resolution of observed spectra towards the pre-stellar core L1544 are challenging the current physical and chemical models. With the aim of further constraining the structure of L1544 as well as…

Astrophysics of Galaxies · Physics 2025-08-29 J. Ferrer Asensio , S. S. Jensen , S. Spezzano , P. Caselli , F. O. Alves , O. Sipilä , E. Redaelli

Using the IRAM 30m telescope, we mapped the methanol emission in the pre-stellar core L1544 and observed singly deuterated methanol (CH$_2$DOH and CH$_3$OD) towards the dust peak of L1544. Non-LTE radiative transfer modelling was performed…

Solar and Stellar Astrophysics · Physics 2014-09-17 Luca Bizzocchi , Paola Caselli , Silvia Spezzano , Elvira Leonardo

We have mapped the dense dark core L1544 in H13CO+(1-0), DCO+(2-1), DCO+(3-2), N2H+(1-0), NTH+(3-2), N2D+(2-1), N2D+(3-2), C18O(1-0), and C17O(1-0) using the IRAM 30-m telescope. We have obtained supplementary observations of HC18O+(1-0),…

Astrophysics · Physics 2019-08-17 P. Caselli , C. M. Walmsley , A. Zucconi , M. Tafalla , L. Dore , P. C. Myers

The chemical evolution of pre-stellar cores during their transition to a protostellar stage is not yet fully understood. Detailed chemical characterizations of these sources are needed to better define their chemistry during star formation.…

This work explores the differences between static and dynamically evolving physico-chemical models of pre-stellar cores. A 3D MHD model of a pre-stellar core embedded in a dynamic star-forming cloud is post-processed using sequentially dust…

Solar and Stellar Astrophysics · Physics 2026-03-19 S. S. Jensen , S. Spezzano , P. Caselli , T. Grassi , O. Sipilä , T. Haugbølle

Lynds 1498 is a pre-protostellar core (PPC) and was one of the initial objects toward which molecular depletion and differentiation was detected. Despite the considerable scrutiny of L1498, there has not been a extensive study of the…

The molecular evolution that occurs in collapsing prestellar cores is investigated. To model the dynamics, we adopt the Larson-Penston (L-P) solution and analogues with slower rates of collapse. For the chemistry, we utilize the new…

Astrophysics · Physics 2009-11-07 Yuri Aikawa , Nagayoshi Ohashi , Eric Herbst

We present Herschel, ALMA Compact Array (ACA), and Caltech Submillimeter Observatory (CSO) observations of the prestellar core in L1689N, which has been suggested to be interacting with a molecular outflow driven by the nearby solar type…

Astrophysics of Galaxies · Physics 2016-08-24 D. C. Lis , H. A. Wootten , M. Gerin , L. Pagani , E. Roueff , F. F. S van der Tak , C. Vastel , C. M. Walmsley

We combine dynamical and non-equilibrium chemical modeling of evolving prestellar molecular cloud cores, and explore the evolution of molecular abundances in the contracting core. We model both magnetic cores, with varying degrees of…

Astrophysics of Galaxies · Physics 2015-06-03 Konstantinos Tassis , Karen Willacy , Harold W. Yorke , Neal J. Turner

The study of deuteration in pre-stellar cores is important to understand the physical and chemical initial conditions in the process of star formation. In particular, observations toward pre-stellar cores of methanol and deuterated…

(Abridged) We present evidence that low-mass starless cores, the simplest units of star formation, are systematically differentiated in their chemical composition. Molecules including CO and CS almost vanish near the core centers, where the…

Astrophysics · Physics 2008-11-26 M. Tafalla , P. C. Myers , P. Caselli , C. M. Walmsley , C. Comito

Pre-stellar cores represent the initial conditions in the process of star and planet formation. Their low temperatures ($<$10 K) allow the formation of thick icy dust mantles, which will be partially preserved in the future protoplanetary…