H-alpha Observations Using Closure Phases at the NPOI
Abstract
We have enhanced the spectral resolution of the Navy Prototype Optical Interferometer (NPOI) at the H-alpha line to 3 nm (FWHM). We use customized filters that suppresses light in the ~600-725 nm window except for light at the H-alpha wavelength (656.3 nm). The bands shortward of 600 nm and longward of 725 nm are used for fringe tracking and for calibrating the system fringe visibility. We have used these filters to observe H-alpha emission from circumstellar material around Be stars. Closure phases from our initial observations of the Be star zeta Tau with three array elements suggest that the H-alpha emission is not centered on the star. We will show these three-element results, as well as recently-acquired data from the NPOI using 4, 5, and 6 stations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2004
- Accession Number
- ADA477298
Entities
People
- David Mozurkewich
- Donald J. Hutter
- G. Gilbreath
- James H. Clark
- John Thomas Armstrong
- Robert B. Hindsley
- Thomas A. Pauls
Organizations
- United States Naval Research Laboratory