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Related papers: Infall models of Class 0 protostars

200 papers

We present molecular line observations made with the IRAM 30-m telescope of the immediate surroundings of a sample of 11 candidate high-mass protostars. These observations are part of an effort to clarify the evolutionary status of a set of…

Astrophysics · Physics 2009-11-06 J. Brand , R. Cesaroni , F. Palla , S. Molinari

We present the results of an extensive mapping survey of 53 `starless' cores in the optically thick line of CS 2-1 and the optically thin lines of N2H+ 1-0 and C18O 1-0. The purpose of this survey was to search for signatures of extended…

Astrophysics · Physics 2009-11-06 Chang Won Lee , Philip C. Myers , Mario Tafalla

Context. This is the third of a series of papers devoted to study in detail and with high-angular resolution intermediate-mass molecular outflows and their powering sources. Aims. The aim of this paper is to study the intermediate-mass YSO…

Astrophysics · Physics 2009-11-13 M. T. Beltran , R. Estalella , J. M. Girart , P. T. P. Ho , G. Anglada

We present ALMA Band 7 molecular line observations of the protostars within the VLA 1623 system. We map C$^{17}$O (3 - 2) in the circumbinary disk around VLA 1623A and the outflow cavity walls of the collimated outflow. We further detect…

We used the NRAO Very Large Array to search for 3.6 cm continuum emission from embedded protostars in a sample of 8 nearby ``starless'' cores that show spectroscopic evidence for infalling motions in molecular emission lines. We detect a…

Astrophysics · Physics 2009-11-07 D. W. A. Harvey , D. J. Wilner , J. Di Francesco , C. -W. Lee , P. C. Myers , J. P. Williams

To study the early phases of massive star formation, we present ALMA observations of SiO(5-4) emission and VLA observations of 6 cm continuum emission towards 32 Infrared Dark Cloud (IRDC) clumps, spatially resolved down to $\lesssim 0.05$…

Astrophysics of Galaxies · Physics 2021-11-17 Mengyao Liu , Jonathan C. Tan , Joshua Marvil , Shuo Kong , Viviana Rosero , Paola Caselli , Giuliana Cosentino

(Abridged) The physical structure of deeply-embedded low-mass protostars (Class 0) on scales of less than 300 AU is still poorly constrained. Determining this is crucial for understanding the physical and chemical evolution from cores to…

Solar and Stellar Astrophysics · Physics 2016-05-04 M. V. Persson , D. Harsono , J. J. Tobin , E. F. van Dishoeck , J. K. Jørgensen , N. Murillo , S. -P. Lai

Due to instrumental limitations and a lack of disk detections, the structure between the envelope and the rotationally supported disk has been poorly studied. This is now possible with ALMA through observations of CO isotopologs and tracers…

We investigate the nature of 24micron sources in M33 which have weak or no associated Halpha emission. Both bright evolved stars and embedded star forming regions are visible as compact infrared sources in the 8 and 24micron maps of M33 and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Edvige Corbelli , Carlo Giovanardi , Francesco Palla , Simon Verley

The evolutionary sequence for high-mass star formation starts with massive starless clumps that go on to form protostellar, young stellar objects and then compact HII regions. While there are many examples of the three later stages, the…

Astrophysics of Galaxies · Physics 2023-05-09 T. G. S. Pillai , J. S. Urquhart , S. Leurini , Q. Zhang , A. Traficante , D. Colombo , K. Wang , L. Gomez , F. Wyrowski

We present dust opacity spectral indexes (beta) of the youngest protostellar systems (so-called Class 0 sources), L1448 IRS 2, L1448 IRS 3, and L1157, obtained between 1.3 mm and 2.7 mm continua, using the Combined Array for Research in…

Solar and Stellar Astrophysics · Physics 2011-02-11 Woojin Kwon , Leslie W. Looney , Lee G. Mundy , Hsin-Fang Chiang , Athol J. Kemball

We perform imaging and analyses of SMA 1.3 mm continuum, C18O (2-1) and 12CO (2-1) line data of 17 Class 0 and 0/I protostars to study their gas kinematics on a 1,000-AU scale. Continuum and C18O (2-1) emission are detected toward all the…

Solar and Stellar Astrophysics · Physics 2015-06-23 Hsi-Wei Yen , Patrick M. Koch , Shigehisa Takakuwa , Paul T. P. Ho , Nagayoshi Ohashi , Ya-Wen Tang

The onset of massive star formation is not well understood because of observational and theoretical difficulties. To find the dense and cold clumps where massive star formation can take place, we compiled a sample of high infrared…

Astrophysics of Galaxies · Physics 2015-06-11 K. L. J. Rygl , F. Wyrowski , F. Schuller , K. M. Menten

We present model spectral energy distributions, colors, polarization, and images for an evolutionary sequence of a low-mass protostar from the early collapse stage (Class 0) to the remnant disk stage (Class III). We find a substantial…

Astrophysics · Physics 2010-04-08 Barbara A. Whitney , Kenneth Wood , J. E. Bjorkman , Martin Cohen

We present a search for outflows towards 51 submillimetre cores in Perseus. With consistently derived outflow properties from a large homogeneous dataset within one molecular cloud we can investigate further the mass dependence and time…

Astrophysics · Physics 2009-11-13 J. Hatchell , G. A. Fuller , J. S. Richer

We are motivated by the recent measurements of dust opacity indices beta around young stellar objects (YSOs), which suggest that efficient grain growth may have occurred earlier than the Class I stage. The present work makes use of abundant…

Solar and Stellar Astrophysics · Physics 2017-05-24 Jennifer I-Hsiu Li , Hauyu Baobab Liu , Yasuhiro Hasegawa , Naomi Hirano

We report centimeter continuum observations with the VLA and the VLBA as well as mid-infrared observations with COMICS/SUBARU toward the components of the YLW 15 very young binary system, VLA 1 and VLA 2. The centimeter emission of the two…

Astrophysics · Physics 2009-11-10 J. M. Girart , S. Curiel , L. F. Rodriguez , M. Honda , J. Canto , Y. K. Okamoto , S. Sako

We present the results of an outflow and infall survey towards a distance limited sample of 31 massive star forming regions drawn from the RMS survey. The presence of young, active outflows is identified from SiO (8-7) emission and the…

Astrophysics of Galaxies · Physics 2018-04-04 Nichol Cunningham , Stuart Lumsden , Toby Moore , Luke Maud , Ignacio. Mendigutia

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

When the planet formation process begins in the disks surrounding young stars is still an open question. Annular substructures such as rings and gaps in disks are intertwined with planet formation, and thus their presence or absence is…