New variability types
The new variability types (ZZO, AM, R, BE, LBV, BLBOO, EP, SRS, LPB)
have been added in the Name-Lists 67- 77 and in the GCVS vol.V.
- ZZO - ZZ Cet type variables of the DO spectral type showing HeII and
CIV absorbtion lines in their spectra.
- AM - AM Her type variables; close binary systems consisting of a
dK-dM type dwarf and of a compact object with strong magnetic
field, characterized by variable linear and circular polarization
of light. The total range of light variations may reach 4-5 mag V.
- R - Close binary systems characterized by the presence of strong
reflection (re-radiation) of the light of the hot star
illuminating the surface of the cooler companion. Light curves
are sinusoidal with the period equal to Porb, maximum brightness
coinciding with the passage of the hot star in front of the
companion. The eclipse may be absent. The range of light
variation is about 0.5-1.0mag V (KV Vel).
- BE - It becomes more and more clear that, although the majority of Be
stars are photometrically variable, not all of them could be
properly called GCAS variables. Quite a number of them show
small-scale variations not necessarily related to shell events; in
some cases the variations are quasi-periodic. By now we are not
able to present an elaborated system of classification for Be
variables, but we adopt a decision that in the cases when a Be
variable cannot be readily described as a GCAS star we give simply
BE for the type of variability.
- EP - Stars showing eclipses by their planets. Prototype: V0376 Peg.
- SRS - Semiregular pulsating red giants with short period (several days
to month), probably high-overtone pulsators. Prototype: AU Ari.
- LPB - For comparatively long-period pulsating B stars (periods exceeding
(LBV) one day).
- BLBOO - The so-called "anomalous Cepheids", i.e. stars with periods
characteristic of comparatively long-period RRAB variables, but
considerably brighter by luminosity (BL Boo = NGC 5466 V19).
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