First detection of the ground-state J/sub K/ = 1/sub 0/. -->. 0/sub 0/ submillimeter transition of interstellar ammonia

Journal Article · Mon Aug 01 04:00:00 EDT 1983 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/184086· OSTI ID:5573007

Keene, J; Blake, G A; Phillips, T G

The J/sub K/ = l/sub 0/..-->..0/sub 0/ transition of ammonia at 572.5 GHz has been detected in OMC-1 from NASA's Kuiper Airborne Observatory. The central velocity of the line (V/sub LSR/roughly-equal9 km s/sup -1/) indicates that it originates in the molecular cloud material, not in the hot core. The derived filling factor of > or approx. =0.09 in a 2' beam implies a source diameter of > or approx. =35'' if it is a single clump. This clump area is much larger than that derived from observations of the l/sub 1/ inversion transition The larger optical depth in the l/sub 0/..-->..0/sub 0/ transition (75--350) can account for the increased source area and line width as compared with those seen in the l/sub 1/ inversion transition.

• Research Organization: California Institute of Technology
• OSTI ID: 5573007
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Journal Name: Astrophys. J., Lett. Ed.; (United States) Vol. 271:1; ISSN AJLEA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMMONIA
EMISSION
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITED STATES
FUNCTIONS
GROUND STATES
HYDRIDES
HYDROGEN COMPOUNDS
INFRARED SPECTRA
INTERSTELLAR GRAINS
LINE WIDTHS
NEBULAE
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
PARTICLES
ROTATIONAL STATES
SPECTRA
SPECTRAL DENSITY
SPECTRAL FUNCTIONS