English
Related papers

Related papers: Systematic Molecular Differentiation in Starless C…

200 papers

This paper presents the first substantial study of the chemistry of the envelopes around a sample of 18 low-mass pre- and protostellar objects for which physical properties have previously been derived from radiative transfer modeling of…

Astrophysics · Physics 2009-11-10 J. K. Jorgensen , F. L. Schoeier , E. F. van Dishoeck

We aim at investigating with high angular resolution the NH3/N2H+ ratio toward the high-mass star-forming region AFGL 5142 in order to study whether this ratio behaves similarly to the low-mass case, for which the ratio decreases from…

Astrophysics of Galaxies · Physics 2015-05-19 Gemma Busquet , Robert Estalella , Qizhou Zhang , Serena Viti , Aina Palau , Paul T. P. Ho , Alvaro Sanchez-Monge

AIMS: To study the structure of nearby (< 500 pc) dense starless and star-forming cores with the particular goal to identify and understand evolutionary trends in core properties, and to explore the nature of Very Low Luminosity Objects (<…

Astrophysics · Physics 2009-11-13 Jens Kauffmann , Frank Bertoldi , Tyler L. Bourke , Neal J. Evans , Chang Won Lee

This paper presents a large spectral line and continuum survey of 8 deeply embedded, low-mass protostellar cores using the Submillimeter Array. Each source was observed in high excitation lines of some of the most common molecular species,…

Although the deuterium fraction is known to be a powerful evolutionary tracer, its variation within individual molecular cloud cores is still poorly understood. The northern $\int$-shaped filament and 20 individual starless cores in the…

We use sub-arcsecond resolution ($\sim$0.4$''$) observations with NOEMA at 1.37 mm to study the dust emission and molecular gas of 18 high-mass star-forming regions. We combine the derived physical and chemical properties of individual…

We investigate the molecular evolution and D/H abundance ratios that develop as star formation proceeds from a dense-cloud core to a protostellar core, by solving a gas-grain reaction network applied to a 1-D radiative hydrodynamic model…

Astrophysics of Galaxies · Physics 2015-06-11 Yuri Aikawa , Valentine Wakelam , Franck Hersant , Robin T. Garrod , Eric Herbst

We have investigated the two-dimensional (R,Z) distribution of deuterated molecular species in circumstellar disks around young stellar objects. The abundance ratios between singly deuterated and normal molecules (``D/H ratios'') in disks…

Astrophysics · Physics 2009-11-07 Y. Aikawa , E. Herbst

(abridged) [...] Methods: In a continued study of the molecular core population of the Pipe Nebula, we present a molecular-line survey of 52 cores. Previous research has shown a variety of different chemical evolutionary stages among the…

Solar and Stellar Astrophysics · Physics 2014-09-05 Jan Forbrich , Karin Öberg , Charles J. Lada , Marco Lombardi , Alvaro Hacar , João Alves , Jill M. Rathborne

We report the first detection of hot molecular cores in the Small Magellanic Cloud, a nearby dwarf galaxy with 0.2 solar metallicity. We observed two high-mass young stellar objects in the SMC with ALMA, and detected emission lines of CO,…

Astrophysics of Galaxies · Physics 2023-04-12 Takashi Shimonishi , Kei E. I. Tanaka , Yichen Zhang , Kenji Furuya

The complexity of physico-chemical models of star formation is increasing, with models that take into account new processes and more realistic setups. These models allow astrochemists to compute the evolution of chemical species throughout…

Astrophysics of Galaxies · Physics 2019-07-17 Thomas H. G. Vidal , Pierre Gratier , Neil Vaytet , Audrey Coutens , Valentine Wakelam

We have observed molecular cloud cores in the Orion A giant molecular cloud (GMC) in CCS, HC3N, DNC, and HN13C to study their chemical characteristics. We have detected CCS in the Orion A GMC for the first time. CCS was detected in about a…

Astrophysics of Galaxies · Physics 2015-05-20 Ken'ichi Tatematsu , Tomoya Hirota , Ryo Kandori , Tomofumi Umemoto

Complex organic molecules (COMs) have been observed towards several low-mass young stellar objects (LYSOs). Small and heterogeneous samples have so far precluded conclusions on typical COM abundances, as well as the origin(s) of abundance…

Solar and Stellar Astrophysics · Physics 2017-06-21 Jennifer B. Bergner , Karin I. Öberg , Robin T. Garrod , Dawn M. Graninger

We aim to characterize the physical and chemical properties of fragmented cores during the earliest evolutionary stages in the very young star-forming regions ISOSS J22478+6357 and ISOSS J23053+5953. NOEMA 1.3 mm data are used in…

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 present high spatial (<300 AU) and spectral (0.07 km/s) resolution Submillimeter Array observations of the dense starless cluster core Oph A-N6, in the 1 mm dust continuum and the 3-2 line of N2H+ and N2D+. The dust continuum…

We aim to investigate the chemistry and gas phase abundance of HNCO and the variation of the HNCO/CS abundance ratio as a diagnostic of the physics and chemistry in regions of massive star formation. A numerical-chemical model has been…

Astrophysics of Galaxies · Physics 2015-05-14 D. M. Tideswell , G. A. Fuller , T. J. Millar , A. J. Markwick

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

In this paper we present the results of a high resolution (5") CARMA and SZA survey of the 3mm continuum emission from 11 of the brightest (at 1.1mm) starless cores in the Perseus molecular cloud. We detect 2 of the 11 cores, both of which…

Astrophysics of Galaxies · Physics 2015-05-19 Scott Schnee , Melissa Enoch , Doug Johnstone , Thomas Culverhouse , Erik Leitch , Daniel P. Marrone , Anneila Sargent

We present a Berkeley-Illinois-Maryland Association (BIMA) Array molecular survey of the star forming core ahead of HH 80N, the optically obscured northern counterpart of the Herbig-Haro objects HH 80/81. Continuum emission at 1.4 mm and 8…

Solar and Stellar Astrophysics · Physics 2011-02-11 Josep M. Masqué , Josep M. Girart , Maria T. Beltrán , Robert Estalella , Serena Viti
‹ Prev 1 4 5 6 7 8 10 Next ›