Advances in ultraviolet observations.
Abstract
The accuracy of available ultraviolet measurements of planetary nebulae is examined, and some interpretations of the data are made. The observed dip in flux at 2200 A can be used to measure extinction if (1) the intrinsic spectrum of the object is relatively smooth over the interval 1700-2600 A, and (2) the intervening medium is characterized by a uniform extinction curve with known properties. It is argued that these conditions are likely to hold, and the extinction calculated on this basis and expressed at E(B-V) is in good correlation with the extinction calculated from the ratio of the H-beta flux to the radio flux. Methods of separating nebular emission from central star emission and measuring the nebular continuum are briefly mentioned.
- Publication:
-
Planetary Nebulae
- Pub Date:
- 1978
- Bibcode:
- 1978IAUS...76...93P
- Keywords:
-
- Astronomical Spectroscopy;
- Planetary Nebulae;
- Satellite Observation;
- Spaceborne Astronomy;
- Ultraviolet Astronomy;
- Continuous Spectra;
- Emission Spectra;
- Error Analysis;
- H Beta Line;
- Stellar Spectra;
- Td-1 Satellite;
- Astrophysics