THE FLUORESCENCE EFFICIENCIES OF THE CN VIOLET BANDS IN COMETS
- Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States)
We have carried out calculations of the fluorescent equilibrium of the CN molecule in the solar radiation field as a function of heliocentric radial velocity and distance. The detailed rotational line intensities of the CN violet 0-0 band have been recalculated for radial velocities between -60 and +60 km s{sup -1} and at 10 distances in steps of {radical}2 from 0.25 to 5.7 AU. Comparisons with observed CN violet 0-0 band profiles yield reasonable agreement and remaining discrepancies are well understood. Based on the derived equilibrium rotational level populations of the ground state, 1-1 band rotational line intensities were also calculated. Total band fluorescence efficiencies for the violet {Delta}{nu} = 0 sequence are tabulated for the above range of distances and velocities, permitting the interpolation to any given comet's observational circumstances. These fluorescence efficiencies, L/N, or 'g-factors', needed to reduce CN emission band fluxes to CN abundances, are also accessible via a Web-based service. The values at any heliocentric distance vary by about a factor of two with varying velocities, but the specific structure of this variation with velocity changes dramatically with distance.
- OSTI ID:
- 21443225
- Journal Information:
- Astronomical Journal (New York, N.Y. Online), Vol. 140, Issue 4; Other Information: DOI: 10.1088/0004-6256/140/4/973; ISSN 1538-3881
- Country of Publication:
- United States
- Language:
- English
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