Submillimeter Wave Astronomy Satellite observations of water vapor toward comet C/1999 H1 (Lee)

Citation
Da. Neufeld et al., Submillimeter Wave Astronomy Satellite observations of water vapor toward comet C/1999 H1 (Lee), ASTROPHYS J, 539(2), 2000, pp. L151-L154
Citations number
16
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICAL JOURNAL
ISSN journal
0004637X → ACNP
Volume
539
Issue
2
Year of publication
2000
Part
2
Pages
L151 - L154
Database
ISI
SICI code
0004-637X(20000820)539:2<L151:SWASOO>2.0.ZU;2-J
Abstract
We have detected the 1(10)-1(01) pure rotational transition of water vapor toward comet C/1999 H1 using the Submillimeter Wave Astronomy Satellite. Ov er the period 1999 May 19.01-23.69 UT, the average integrated antenna tempe rature was 1.79 +/- 0.03 K km s(-1) within a 3.'3 x 4.'5 (FWHM) elliptical beam. For an assumed ortho-to-para ratio of 3, we estimate the total water production rate as 8 x 10(28) s(-1). This value lies approximately 50% abov e the value estimated by Biver et al. from contemporaneous radio observatio ns of hydroxyl molecules. The observed line width of 1.8 km s(-1) (FWHM) is broader than the instrumental profile and suggests an intrinsic line width of about 1.4 km s(-1) (FWHM). The data, taken during a portion of every 97 minute spacecraft orbit over a 4.68 day period, provide no evidence for va riability.