Water production of comets derived from observations of [OI] (6300 Å) and H2O+ (6150 Å): comets C/1998 U5 (Linear) and C/1999 J3 (Linear)
Abstract
The gas production rates of comets C/1998 U5 (Linear) and C/1999 J3 (Linear) are determined from observations obtained at the 2m-RCC telescope of Pik Terskol Observatory. In case of Comet C/1998 U5 the water production rate is derived from a classical Fabry-Perot interferogram of the [OI] 1D → 3P transition at 6300 Å. The interferogram shows the cometary [OI] line well separated from the night glow line because of the comet's radial velocity of 21.7 km s-1. The high spectral resolution of the interferogram allows to resolve the cometary [OI] line with respect to neighbouring NH2 lines. The [OI] emission is detected up to distances of 30,000 km from the nucleus. The water production rate amounts to 1.0×1028 molecules s-1. An H2O+ column density map of Comet C/1999 J3 (Linear) is used to infer the total gas production rate of this comet using the MHD similarity law. This method is based on the theory of comet-solar wind interaction. Assuming average solar wind behavior we determine a gas production rate of 1.6×1028 molecules s-1.
- Publication:
-
Kinematika i Fizika Nebesnykh Tel Supplement
- Pub Date:
- September 2000
- Bibcode:
- 2000KFNTS...3..262J