Observations and analyses of interstellar cyanogen

Journal Article · Mon Sep 15 04:00:00 EDT 1980 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/158294· OSTI ID:6636417

Churchwell, E

CN(113.5 GHz) has been detected at two (and possibly four) locations in the Taurus dark cloud complex and in 12 molecular clouds associated with H II regions. Partial maps of CN line intensities were obtained for DR 21 and Sgr A. In those sources where the CN hyperfine components were observed, line opacities and excitation temperatures have been estimated and used to derive CN column densities in the ground rotational state. Total Cn column densities were estimated by applying a large velocity gradient (LVG) model to estimate the fraction of CN in unobserved states. The primary results of this study are the following: (1) CN is apparently about as abundant as CS in molecular clouds associated with H II regions. (2) Opaticities in the N=1..-->..0 lines of CN are generally small relative to unity. (3) If CN collision cross sections are approximately the same as those of CO, then over a wide range of temperatures and densities a large fraction of CN should be in the ground rotational state. (4) In Taurus, CN appears to be spatially correlated with NH/sub 3/ and anticorrelated with HC/sub 3/N. (5) In DR 21, CN has a distribution similar to that of HCN and C/sub 2/H (a narrow N-S ridge with HPW approx.9.5' x 5'). Relatively large variations of opacity and velocity are apparent in the CN lines along the ridge.

• Research Organization: Washburn Observatory, University of Wisconsin, Madison
• OSTI ID: 6636417
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 242:3; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
CHEMISTRY
COSMIC RADIO SOURCES
COSMOCHEMISTRY
CYANOGEN
ELECTROMAGNETIC RADIATION
ENERGY LEVELS
ENERGY SPECTRA
EXCITED STATES
FUNCTIONS
H2 REGIONS
INTERSTELLAR GRAINS
MOLECULES
NEBULAE
OPACITY
OPTICAL PROPERTIES
PARTICLES
PHYSICAL PROPERTIES
RADIATIONS
RADIOWAVE RADIATION
ROTATIONAL STATES
SPECTRA
SPECTRAL DENSITY
SPECTRAL FUNCTIONS