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Related papers: OVRO N2H+ Observations of Class 0 Protostars: Cons…

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We have performed a 1 square degree 1.2mm dust continuum survey in the rho Oph molecular cloud. We detect a number of previously unknown sources, ranging from extended cores over compact, starless cores to envelopes surrounding young…

Astrophysics · Physics 2009-11-11 Thomas Stanke , Michael D. Smith , Roland Gredel , Tigran Khanzadyan

We present results of an extensive mapping survey of N2H+(1-0) in about 60 low mass cloud cores already mapped in the NH3(1,1) inversion transition line. The survey has been carried out at the FCRAO antenna with an angular resolution about…

Astrophysics · Physics 2010-04-06 Paola Caselli , Priscilla J. Benson , Philip C. Myers , Mario Tafalla

The results are presented of a molecular line survey to search for the spectral signature of infall towards 77 850 micron continuum sources believed to be candidate high mass protostellar objects. Up to six different transitions, HCO+ 1-0,…

Astrophysics · Physics 2009-11-11 G. A. Fuller , S. J. Williams , T. K. Sridharan

We present high angular resolution 1.3 mm and 850 um dust continuum data obtained with the Submillimeter Array toward 33 Class 0 protostars in nearby clouds (distance < 500 pc), which represents so far the largest survey toward protostellar…

We present combined BIMA interferometer and IRAM 30 m Telescope data of N2H+ 1-0 line emission across the nearby dense, star forming core Ophiuchus A (Oph A) at high linear resolution (e.g., ~1000 AU). Six maxima of integrated line…

Astrophysics · Physics 2009-08-03 James Di Francesco , Philippe Andre , Philip C. Myers

We aim to determine the physical and chemical properties of dense cores in Orion B9. We observed the NH3(1,1) and (2,2), and the N2H+(3-2) lines towards the submm peak positions. These data are used in conjunction with our LABOCA 870 micron…

Astrophysics of Galaxies · Physics 2015-05-19 Oskari Miettinen , Jorma Harju , Lauri K. Haikala , Mika Juvela

Using the archive data of the H13CO+ (J=1-0) line emission taken with the Nobeyama 45 m radio telescope with a spatial resolution of about 0.01pc, we have identified 68 dense cores in the central dense region of the rho Ophiuchi main cloud.…

Solar and Stellar Astrophysics · Physics 2015-05-13 Hajime Maruta , Fumitaka Nakamura , Ryoichi Nishi , Norio Ikeda , Yoshimi Kitamura

We present a characterization of the binary protostar system that is forming within a dense core in the isolated dark cloud BHR71. The pair of protostars, IRS1 and IRS2, are both in the Class 0 phase, determined from observations that…

We have analyzed the angular momentum of the molecular cloud cores in the Orion A giant molecular cloud observed in the N2H+ J = 1-0 line with the Nobeyama 45 m radio telescope. We have measured the velocity gradient using position velocity…

Abridged: We use three-dimensional SPH simulations to investigate the collapse of low-mass prestellar cores and the formation and early evolution of protostellar discs. The initial conditions are slightly supercritical Bonnor-Ebert spheres…

Astrophysics of Galaxies · Physics 2015-05-13 S. Walch , A. Burkert , A. Whitworth , T. Naab , M. Gritschneder

The ``integral-shaped filament'' of the Orion A giant molecular cloud was mapped in N2H+, and its northern end, the OMC-2/3 region was observed also in HC3N and CCS. The N2H+ distribution is similar to the dust continuum distribution,…

Astrophysics · Physics 2015-05-13 K. Tatematsu , R. Kandori , T. Umemoto , Y. Sekimoto

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…

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 observed the clustered star forming complex NGC1333 with the BIMA and FCRAO telescopes in the transitions HCO+(1-0) and N2H+(1-0) over an 11'x11' area with resolution ~10" (0.015pc). The N2H+ emission follows very closely the…

N2H+ observations of molecular cloud cores in Taurus with the Nobeyama 45 m radio telescope are reported. We compare ``cores with young stars'' with ``cores without young stars''. The differences in core radius, linewidth, and core mass are…

Astrophysics · Physics 2009-11-10 K. Tatematsu , T. Umemoto , R. Kandori , Y. Sekimoto

We analyze the dense gas kinematics in two Class 0/I protostellar cores, Per 30 and NGC 1333 IRAS 7, in the Perseus molecular cloud to determine whether their velocity structures are indicative of rotation. We examine the hyperfine…

Astrophysics of Galaxies · Physics 2025-04-22 Erica Behrens , Adele Plunkett , Zhi-Yun Li

Observing and characterizing pre- and protostellar cores in the earliest and densest stages of star formation is challenging due to their short timescales and high densities, limiting the suitable tracers and targets. We conducted…

We have measured the deuterium fractionation (through the column density ratio N(N2D+)/N(N2H+)) and the CO depletion factor (ratio between expected and observed CO abundance) in a sample of 10 high-mass protostellar candidates, in order to…

Astrophysics · Physics 2009-11-11 F. Fontani , P. Caselli , A. Crapsi , R. Cesaroni , S. Molinari , L. Testi , J. Brand

We present the results of N2H+(1-0) observations of 35 dense molecular cloud cores from the northern and southern hemispheres where massive stars and star clusters are formed. Line emission has been detected in 33 sources, for 28 sources…

Astrophysics · Physics 2009-11-07 L. Pirogov , I. Zinchenko , P. Caselli , L. E. B. Johansson , P. C. Myers

We present millimeter interferometric observations of the young stellar object SVS13 in NCG1333 in the N2H+(1-0) line and at 1.4 and 3mm dust continuum, using the IRAM Plateau de Bure interferometer. The results are complemented by infrared…

Astrophysics · Physics 2011-02-11 Xuepeng Chen , Ralf Launhardt , Thomas Henning
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