Discovery of Four New Massive and Dense Cold Cores

We report the identification, from a 1.2 mm dust continuum emission survey toward massive star-forming regions, of four strong 1.2 mm sources without counterparts at mid-infrared (Midcourse Space Experiment [MSX]) and far-infrared (IRAS) wavelengths. They have radii in the range 0.2-0.3 pc, dust temperatures ≤17 K, masses in the range 4 × 102-2 × 103 M☉, and densities of ~2 × 105 cm-3. We suggest that these objects are massive and dense cold cores that will eventually collapse to form high-mass stars.

[1]  L. Bronfman,et al.  Discovery of a Massive Protostar near IRAS 18507+0121 , 2003, astro-ph/0310774.

[2]  R. Pudritz,et al.  Gravitational Collapse of Filamentary Magnetized Molecular Clouds , 2003, astro-ph/0306476.

[3]  G. Garay,et al.  A Triple Radio Continuum Source Associated with IRAS 16547-4247: A Collimated Stellar Wind Emanating from a Massive Protostar , 2003 .

[4]  Y. Shirley,et al.  The Physical Conditions for Massive Star Formation: Dust Continuum Maps and Modeling , 2002, astro-ph/0207322.

[5]  T. K. Sridharan,et al.  High-Mass Proto-Stellar Candidates - II : Density structure from dust continuum and CS emission , 2001, astro-ph/0110370.

[6]  James M. Stone,et al.  Density, Velocity, and Magnetic Field Structure in Turbulent Molecular Cloud Models , 2000, astro-ph/0008454.

[7]  R. Klessen,et al.  The Formation of Stellar Clusters: Gaussian Cloud Conditions. I. , 1999, astro-ph/9904090.

[8]  J. Fiege,et al.  Helical fields and filamentary molecular clouds — II. Axisymmetric stability and fragmentation , 1999, astro-ph/9902385.

[9]  N. Evans Physical conditions in regions of star formation , 1999, astro-ph/9905050.

[10]  K. Menten,et al.  Hot Gas and Dust in a Protostellar Cluster near W3(OH) , 1999, astro-ph/9901261.

[11]  Martin G. Cohen,et al.  A Population of Cold Cores in the Galactic Plane , 1998 .

[12]  R. Plume,et al.  Dense Gas and Star Formation: Characteristics of Cloud Cores Associated with Water Masers , 1996, astro-ph/9609061.

[13]  M. Juvela Studies of dense molecular cores in regions of massive star formation. IV. Multitransition CS-study towards , 1996 .

[14]  Y. Nakajima,et al.  Formation and Evolution of Filamentary Molecular Clouds with Oblique Magnetic Field , 1996 .

[15]  Luis F. Rodríguez,et al.  Radio Continuum, Ammonia and Water Maser Observations of Bright, Unassociated IRAS Point Sources , 1993 .

[16]  R. Laureijs,et al.  The temperature of large dust grains in molecular clouds , 1991 .

[17]  N. Evans,et al.  A survey of CS J = 7 → 6 in regions of massive star formation , 1991 .

[18]  A. Wolfendale,et al.  Corrections to virial estimates of molecular cloud masses , 1988 .

[19]  R. Larson Cloud fragmentation and stellar masses , 1985 .

[20]  D. Gezari The remarkable 400 micron source NGC 6334/I/North/ , 1982 .

[21]  R. Larson Mass spectra of young stars , 1981 .