U, B, V photometry and spectroscopy of HM Sagittae in 1978
Abstract
During 1978 the peculiar object HM Sge faded gradually in all the U, B, V bands; the mean B-V color index increased somewhat, while U-B was slightly smaller than in 1977. Rapid light fluctuations of up to 0.1m amplitude again occurred, lasting about a day. Several forbidden lines were significantly enhanced relative to the hydrogen emission lines. High-dispersion coude spectrograms show that different hydrogen lines have similar profiles, implying that their great width (plus or minus 2000 km/sec) is due to the Doppler effect.
- Publication:
-
Soviet Astronomy Letters
- Pub Date:
- December 1979
- Bibcode:
- 1979SvAL....5..349B
- Keywords:
-
- Emission Spectra;
- Stellar Spectrophotometry;
- Ubv Spectra;
- Visual Photometry;
- Forbidden Bands;
- Hydrogen;
- Light Curve;
- Oxygen Spectra;
- Ultraviolet Photometry;
- Astronomy;
- EMISSION SPECTRA;
- STELLAR SPECTROPHOTOMETRY;
- UBV SPECTRA;
- VISUAL PHOTOMETRY;
- FORBIDDEN BANDS;
- HYDROGEN;
- LIGHT CURVE;
- OXYGEN SPECTRA;
- ULTRAVIOLET PHOTOMETRY