Methyl cyanide observations toward massive protostars

V. Rosero, P. Hofner, S. Kurtz, John H Bieging, E. D. Araya

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

We report the results of a survey in the CH3CN J = 12 → 11 transition toward a sample of massive proto-stellar candidates. The observations were carried out with the 10 m Submillimeter Telescope on Mount Graham, AZ. We detected this molecular line in 9 out of 21 observed sources. In six cases this is the first detection of this transition. We also obtained full beam sampled cross-scans for five sources which show that the lower K-components can be extended on the arcminute angular scale. The higher K-components, however, are always found to be compact with respect to our 36″ beam. A Boltzmann population diagram analysis of the central spectra indicates CH3CN column densities of about 1014 cm-2, and rotational temperatures above 50 K, which confirms these sources as hot molecular cores. Independent fits to line velocity and width for the individual K-components resulted in the detection of an increasing blueshift with increasing line excitation for four sources. Comparison with mid-infrared (mid-IR) images from the SPITZER GLIMPSE/IRAC archive for six sources show that the CH3CN emission is generally coincident with a bright mid-IR source. Our data clearly show that the CH3CN J = 12 → 11 transition is a good probe of the hot molecular gas near massive protostars, and provide the basis for future interferometric studies.

Original languageEnglish (US)
Article number12
JournalAstrophysical Journal, Supplement Series
Volume207
Issue number1
DOIs
StatePublished - Jul 2013

Fingerprint

protostars
cyanide
acetonitrile
diagram
probe
gas
high temperature gases
molecular gases
temperature
diagrams
detection
telescopes
probes
excitation
analysis
comparison

Keywords

  • ISM: molecules
  • stars: formation

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Methyl cyanide observations toward massive protostars. / Rosero, V.; Hofner, P.; Kurtz, S.; Bieging, John H; Araya, E. D.

In: Astrophysical Journal, Supplement Series, Vol. 207, No. 1, 12, 07.2013.

Research output: Contribution to journalArticle

Rosero, V. ; Hofner, P. ; Kurtz, S. ; Bieging, John H ; Araya, E. D. / Methyl cyanide observations toward massive protostars. In: Astrophysical Journal, Supplement Series. 2013 ; Vol. 207, No. 1.
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