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Title: THE BOLOCAM GALACTIC PLANE SURVEY. V. HCO{sup +} AND N{sub 2}H{sup +} SPECTROSCOPY OF 1.1 mm DUST CONTINUUM SOURCES

Abstract

We present the results of observations of 1882 sources in the Bolocam Galactic Plane Survey (BGPS) at 1.1 mm with the 10 m Henrich Hertz Telescope simultaneously in HCO{sup +} J = 3-2 and N{sub 2}H{sup +} J = 3-2. We detect 77% of these sources in HCO{sup +} and 51% in N{sub 2}H{sup +} at greater than 3{sigma}. We find a strong correlation between the integrated intensity of both dense gas tracers and the 1.1 mm dust emission of BGPS sources. We determine kinematic distances for 529 sources (440 in the first quadrant breaking the distance ambiguity and 89 in the second quadrant). We derive the size, mass, and average density for this subset of clumps. The median size of BGPS clumps is 0.75 pc with a median mass of 330 M{sub sun} (assuming T{sub Dust} = 20 K). The median HCO{sup +} linewidth is 2.9 km s{sup -1} indicating that BGPS clumps are dominated by supersonic turbulence or unresolved kinematic motions. We find no evidence for a size-linewidth relationship for BGPS clumps. We analyze the effects of the assumed dust temperature on the derived clump properties with a Monte Carlo simulation and find that changing the temperature distributionmore » will change the median source properties (mass, volume-averaged number density, surface density) by factors of a few. The observed differential mass distribution has a power-law slope that is intermediate between that observed for diffuse CO clouds and the stellar initial mass function. BGPS clumps represent a wide range of objects (from dense cores to more diffuse clumps) and are typically characterized by larger sizes and lower densities than previously published surveys of high-mass star-forming regions. This collection of objects is a less-biased sample of star-forming regions in the Milky Way that likely span a wide range of evolutionary states.« less

Authors:
; ;  [1]
  1. Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)
Publication Date:
OSTI Identifier:
21562477
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal, Supplement Series
Additional Journal Information:
Journal Volume: 195; Journal Issue: 2; Other Information: DOI: 10.1088/0067-0049/195/2/14; Journal ID: ISSN 0067-0049
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CLOUDS; COMPUTERIZED SIMULATION; DENSITY; DISTANCE; DUSTS; EMISSION; MASS; MILKY WAY; MONTE CARLO METHOD; SPECTROSCOPY; CALCULATION METHODS; GALAXIES; PHYSICAL PROPERTIES; SIMULATION

Citation Formats

Schlingman, Wayne M., Shirley, Yancy L., and Schenk, David E., E-mail: wschlingman@as.arizona.edu, E-mail: yshirley@as.arizona.edu, E-mail: daves24@email.arizona.edu. THE BOLOCAM GALACTIC PLANE SURVEY. V. HCO{sup +} AND N{sub 2}H{sup +} SPECTROSCOPY OF 1.1 mm DUST CONTINUUM SOURCES. United States: N. p., 2011. Web. doi:10.1088/0067-0049/195/2/14.
Schlingman, Wayne M., Shirley, Yancy L., & Schenk, David E., E-mail: wschlingman@as.arizona.edu, E-mail: yshirley@as.arizona.edu, E-mail: daves24@email.arizona.edu. THE BOLOCAM GALACTIC PLANE SURVEY. V. HCO{sup +} AND N{sub 2}H{sup +} SPECTROSCOPY OF 1.1 mm DUST CONTINUUM SOURCES. United States. doi:10.1088/0067-0049/195/2/14.
Schlingman, Wayne M., Shirley, Yancy L., and Schenk, David E., E-mail: wschlingman@as.arizona.edu, E-mail: yshirley@as.arizona.edu, E-mail: daves24@email.arizona.edu. Mon . "THE BOLOCAM GALACTIC PLANE SURVEY. V. HCO{sup +} AND N{sub 2}H{sup +} SPECTROSCOPY OF 1.1 mm DUST CONTINUUM SOURCES". United States. doi:10.1088/0067-0049/195/2/14.
@article{osti_21562477,
title = {THE BOLOCAM GALACTIC PLANE SURVEY. V. HCO{sup +} AND N{sub 2}H{sup +} SPECTROSCOPY OF 1.1 mm DUST CONTINUUM SOURCES},
author = {Schlingman, Wayne M. and Shirley, Yancy L. and Schenk, David E., E-mail: wschlingman@as.arizona.edu, E-mail: yshirley@as.arizona.edu, E-mail: daves24@email.arizona.edu},
abstractNote = {We present the results of observations of 1882 sources in the Bolocam Galactic Plane Survey (BGPS) at 1.1 mm with the 10 m Henrich Hertz Telescope simultaneously in HCO{sup +} J = 3-2 and N{sub 2}H{sup +} J = 3-2. We detect 77% of these sources in HCO{sup +} and 51% in N{sub 2}H{sup +} at greater than 3{sigma}. We find a strong correlation between the integrated intensity of both dense gas tracers and the 1.1 mm dust emission of BGPS sources. We determine kinematic distances for 529 sources (440 in the first quadrant breaking the distance ambiguity and 89 in the second quadrant). We derive the size, mass, and average density for this subset of clumps. The median size of BGPS clumps is 0.75 pc with a median mass of 330 M{sub sun} (assuming T{sub Dust} = 20 K). The median HCO{sup +} linewidth is 2.9 km s{sup -1} indicating that BGPS clumps are dominated by supersonic turbulence or unresolved kinematic motions. We find no evidence for a size-linewidth relationship for BGPS clumps. We analyze the effects of the assumed dust temperature on the derived clump properties with a Monte Carlo simulation and find that changing the temperature distribution will change the median source properties (mass, volume-averaged number density, surface density) by factors of a few. The observed differential mass distribution has a power-law slope that is intermediate between that observed for diffuse CO clouds and the stellar initial mass function. BGPS clumps represent a wide range of objects (from dense cores to more diffuse clumps) and are typically characterized by larger sizes and lower densities than previously published surveys of high-mass star-forming regions. This collection of objects is a less-biased sample of star-forming regions in the Milky Way that likely span a wide range of evolutionary states.},
doi = {10.1088/0067-0049/195/2/14},
journal = {Astrophysical Journal, Supplement Series},
issn = {0067-0049},
number = 2,
volume = 195,
place = {United States},
year = {2011},
month = {8}
}