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We have recently developed a coupled chemistry-emission model for the greenand red-doublet emissions of atomic oxygen on comet Hyakutake. In the presentwork we applied our model to comet Hale-Bopp, which had an order of magnitudehigher H2O production rate than comet Hyakutake, to evaluate the photochemistryassociated with the production and loss of O(1S) and O(1D) atoms and emissionprocesses of green and red-doublet lines. We present the wavelength-dependentphoto-attenuation rates for different photodissociation processes forming O(1S)and O(1D). The calculated radiative efficiency profiles of O(1S) and O(1D)atoms show that in comet Hale-Bopp the green and red-doublet emissions areemitted mostly above radial distances of 10^3 and 10^4 km, respectively. Themodel calculated [OI] 6300 A emission surface brightness and average intensityover the Fabry-P{\'e}rot spectrometer field of view are consistent with theobservation of Morgenthaler et al. (2001), while the intensity ratio of greento red-doublet emission is in agreement with the observation of Zhang et al.(2001). In comet Hale-Bopp, for cometocentric distances less than 10^5 km, theintensity of [OI] 6300 A line is mainly governed by photodissociation of H2O.Beyond 10^5 km, O(1D) production is dominated by photodissociation of the waterphotochemical daughter product OH. Whereas the [OI] 5577 A emission line iscontrolled by photodissociation of both H2O and CO2. The calculated mean excessenergy in various photodissociation processes show that the photodissociationof CO2 can produce O(1S) atoms with higher excess velocity compared to thephotodissociation of H2O. Thus, our model calculations suggest that involvementof multiple sources in the formation of O(1S) could be a reason for the largerwidth of green line than that of red-doublet emission lines observed in severalcomets.

Model for Atomic Oxygen Visible Line Emissions in Comet C/1995 O1 Hale-Bopp