Extreme Ultraviolet Spectrum of epsilon Canis Majoris between 600-920 Angstroms
Abstract
We present the spectrum the brightest known extreme ultraviolet source, epsilon Canis Majoris, between 600 and 920 Angstroms. epsilon Canis Majoris (B2 II) was discovered to be the brightest EUV source in the sky during the Extreme Ultraviolet Explorer (EUVE) all-sky survey. Subsequent spectroscopic observations found an anomolously low neutral hydrogen column density, allowing for the first time the observation of a B star between 500 and 730 Angstroms. Unexpectedly, the spectrum is still increasing at 730 Angstroms. By observing epsilon CMa between 600 and 920 Angstroms, the spectrum of epsilon CMa is now complete from the x-ray thru to the infrared. This provides a unique opportunity for studying the atmospheres of B stars and refining the current atmospheric models, which cannot currently model the stellar flux from epsilon CMa. epsilon CMa was observed on March 4, 1996 from White Sands Missile Range using a sounding rocket borne spectrograph. The spectrum has a resolution ranging between 1000 at 735 Angstroms to 450 at 900 Angstroms . Two data sets were acquired during the flight; one with a tin filter, to block out potential scattered light longward of 920 Angstroms, and one without the filter. We will present the spectrum epsilon CMa and discuss and the current state of our analysis.
- Publication:
-
American Astronomical Society Meeting Abstracts #188
- Pub Date:
- May 1996
- Bibcode:
- 1996AAS...188.5802W