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Towards a Multi-Dimensional Stellar Classification System
Stock, J.; Agostinho, R.; Rose, J. A. +2 more
Practically all the MK spectral types known today are the result of visual inspection of photographic spectra. This includes the monumental work by Nancy Houk. Two questions related to the MK system remained unanswered all along, namely 1) How accurate are the luminosities and intrinsic colors derived from these types? And 2) Can the classificatio…
The Secondary Star in AM CVn
Solheim, J. -E.; Nymark, T. K.
The spectrum of AM CVn shows no definite sign of a secondary star, but through black body calculations of the spectra of the primary, disc and secondary objects, we find that if a one-temperature model for the secondary is assumed, a secondary which is cooler than 5000 K may be present without being seen in the spectrum. There is some excess flux …
HST Observations of the DAV White Dwarf G 226--29
Kepler, S. O.; Robinson, E. L.; Nather, R. E.
We observed G 226-29 for 15 hours with the HST and detected two problems in spectrograms obtained with the post-COSTAR Faint Object Spectrograph and the G160L grating. First, using the 1 arcsec entrance aperture with a triple peakup, we found a strong ( =~ 3 %) modulation of the total count rate on a time scale similar to the HST orbital period. S…
Progress report on the radial velocity measurement programme of Population II stars.
Bartkevičius, A.; Sperauskas, J.
The Population II radial velocity measurement programme was started in 1988 and was carried out during six observing runs. Metal-deficient stars, components of Population II visual binaries or common proper motion pairs, suspected radial velocity variables, HIPPARCOS programme stars are included into the observing programme. The measurements were …
HIPPARCOS programme for field metal-deficient F-M stars
Bartkevicius, A.
Bartkevicius A., Sperauskas J., Rastorguev A.S., Tokovinin
Rastorguev, A. S.; Bartkevicius, A.; Sperauskas, J. +1 more
Radial velocity measurements are presented for 81 Population II stars. The sample comprises components of metal-poor binary stars, spectroscopic binary candidates, high latitude supergiants, metal-deficient stars with spectroscopic determinations of Fe/H, HIPPARCOS program stars, and some other stars of metal-poor population. The radial velocity m…
A study of the IUE ultraviolet spectrum of KHI 02 Orionis.
Sapar, L.; Sapar, A.
The IUE ultraviolet spectrum of eta CMa.
Sapar, Lili; Sapar, Arved
The results of a study of the high-resolution IUE spectrum of Eta CMa in the range 1,170-3,000 A are outlined. The observed spectrum has the best fit to the model spectrum with Teff = 1,3000 K and log g = 2. Computer recognition and identification of about 1,700 observed spectral features has been carried out. The resonance lines of CII, SiIV, AlI…