NA D and CA K emission associated with HD 44179 (The Red Rectangle).
Abstract
A high-spectral-resolution investigation of 'interstellar' lines in the form of narrow-band emission in the spectrum of the late B type star HD 44179 is recounted. Observations of spectral regions centered on the K line of CaII (3933.66 angstroms) and between the D lines of NaI (5889.95, 5895.92 angstroms) were obtained at the Coude focus of the 74-inch telescope of the Mount Stromlo and Siding Spring Observatories, using Echell and cross-disperser gratings, 32-inch camera, and photon-counting arrays. In the profiles illustrated, both profiles contain prominent narrow emission and wider underlying absorption. The emission consists of two narrow components with heliocentric velocities of 13.4 and 23.0 km/s and half-intensity widths (uncorrected) of 6.3 and 4.7 km/s respectively. The absorption probably extends between -13 and 43 km/s, with a peak absorption of about 50 percent. The double emission lines might be explained as arising from plasma streams flowing through a bicone or as evidence that the star is binary. Further observations are planned to try to understand this puzzling system.
- Publication:
-
Publications of the Astronomical Society of Australia
- Pub Date:
- 1983
- DOI:
- 10.1017/S1323358000016921
- Bibcode:
- 1983PASA....5..219W
- Keywords:
-
- B Stars;
- D Lines;
- Emission Spectra;
- K Lines;
- Stellar Spectra;
- Line Spectra;
- Radial Velocity;
- Astrophysics