A Study of Radial Velocities in Diffuse Emission Regions Using a Fabry-Perot Interferometer.
Abstract
A photographic Fabry-Perot interferometer was built for the University of Maryland's 20-inch telescope for the study of the radial velocities of diffuse emission nebulae. Observations of S101, S112, IC5146, NGC281, and IC1795 were made and radial velocities at many points within each nebula were determined with an estimated error of plus or minus 3 km/sec. Average heliocentric radial velocities were obtained for each nebula and they agree well with those found by other observers. For S112 and IC5146, a systematic difference of 6-8 km/sec in the radial velocities between the east and west sides of the nebulae was observed. This phenomenon is attributed to the 'braking' effect of cold gas which appears to be associated with the western side of both nebulae. Ring half-widths were obtained for S112, IC5146 and NGC281. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1968
- Accession Number
- AD0718838
Entities
People
- Ray A. Williamson
Organizations
- University of Maryland