Observation of Ultraviolet Light VAriations of POP II Cepheids
Abstract
We want to study the changes of the ultraviolet energy distributions in Pop II cepheids, and see whether emission lines during maximum light can be detected. The gradient of the energy distributions for longer wavelengths (lambda >1900A) together with studies of the discontinuities at 2600A and at 1700A (for the brighter stars) will permit to determine the metal abundances and the effective temperatures as a function of phase. For k Pav we will in connection with radial velocity measurements be able to determine radii. Comparision with stellar evolution calculations will yield masses for these stars. A comparison of spectra for W Vir and ST Pup both with periods of 17^d but vastly different spectral types will be very interesting. The metal abundances are expected to be very different.
- Publication:
-
IUE Proposal
- Pub Date:
- 1982
- Bibcode:
- 1982iue..prop.1055B