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Title: CARMA LARGE AREA STAR FORMATION SURVEY: STRUCTURE AND KINEMATICS OF DENSE GAS IN SERPENS MAIN

We present observations of N{sub 2}H{sup +} (J = 1 → 0), HCO{sup +} (J = 1 → 0), and HCN (J = 1 → 0) toward the Serpens Main molecular cloud from the CARMA Large Area Star Formation Survey (CLASSy). We mapped 150 arcmin{sup 2} of Serpens Main with an angular resolution of ∼7''. The gas emission is concentrated in two subclusters (the NW and SE subclusters). The SE subcluster has more prominent filamentary structures and more complicated kinematics compared to the NW subcluster. The majority of gas in the two subclusters has subsonic to sonic velocity dispersions. We applied a dendrogram technique with N{sub 2}H{sup +}(1-0) to study the gas structures; the SE subcluster has a higher degree of hierarchy than the NW subcluster. Combining the dendrogram and line fitting analyses reveals two distinct relations: a flat relation between nonthermal velocity dispersion and size, and a positive correlation between variation in velocity centroids and size. The two relations imply a characteristic depth of 0.15 pc for the cloud. Furthermore, we have identified six filaments in the SE subcluster. These filaments have lengths of ∼0.2 pc and widths of ∼0.03 pc, which is smaller than a characteristic width ofmore » 0.1 pc suggested by Herschel observations. The filaments can be classified into two types based on their properties. The first type, located in the northeast of the SE subcluster, has larger velocity gradients, smaller masses, and nearly critical mass-per-unit-length ratios. The other type, located in the southwest of the SE subcluster, has the opposite properties. Several YSOs are formed along two filaments which have supercritical mass per unit length ratios, while filaments with nearly critical mass-per-unit-length ratios are not associated with YSOs, suggesting that stars are formed on gravitationally unstable filaments.« less
Authors:
; ; ; ; ; ;  [1] ; ; ;  [2] ;  [3] ; ;  [4] ;  [5] ;  [6] ;  [7] ;  [8] ;  [9] ;  [10] ;  [11] more »; « less
  1. Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)
  2. Department of Astronomy, University of Illinois, Urbana-Champaign, IL 61801 (United States)
  3. Departments of Physics and Statistics, University of British Columbia, Okanagan Campus, 3333 University Way, Kelowna BC V1V 1V7 (Canada)
  4. Department of Astronomy, Yale University, PO Box 208101, New Haven, CT 06520-8101 (United States)
  5. Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)
  6. Steward Observatory, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)
  7. SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen (Netherlands)
  8. Max Planck Institut für Radioastronomie, Auf dem Hügel 69 D-53121, Bonn Germany (Germany)
  9. National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States)
  10. Astronomy Department, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
  11. Department of Physics and Institute of Theoretical and Computational Physics, University of Crete, PO Box 2208, GR-710 03, Heraklion, Crete (Greece)
Publication Date:
OSTI Identifier:
22364871
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 797; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CLOUDS; COMPARATIVE EVALUATIONS; CORRELATIONS; FILAMENTS; HYDROCYANIC ACID; LENGTH; MOLECULES; RESOLUTION; STAR CLUSTERS; STAR EVOLUTION; STARS; VARIATIONS; VELOCITY