LITHIUM-RICH CLASSICAL CEPHEID V1033 CYG: EVOLUTIONARY STATUS

Анотація

We investigate evolutional status of
cepheid V1033 Cyg in this work, its period of light
variation consists 4 d .94 and the star is a real candidate
on first crossing of instability stripe (IS) (as well as
α of UMi). At first crossing of instability stripe, that
lasts all close 1000 years, cepheids demonstrate the
rapid increase of period, sometimes is a presence of
strong line of lithium 6707 ˚ A. Such objects knows only
four in our Galaxy, one of them - V1033 Cyg. During
included in a instability stripe amplitude of pulsations
headily grows from a zero to some permanent size, and
on leaving from (IS) - again falls to a zero. For verifica-
tion this phenomenon in the Astronomical observatory
of Odesa National University (Ukraine) on the 48-cm
telescope AZT-3, equipped by CCD photometer with
the optical sensor Sony ICX429ALL, a 1864 measuring
of light V1033 Cyg were done in the filter of V and
713 in the filter R, that are partly presented in the
Table. 1 and Fig. 2, and fully accessible to address
http://cdsarc.ustrasbg.fr/viz-bin/cat. Considerable
change of amplitude it is not got by us. The position
of cepheid is certain by us in the (IS) - it appeared that
star is near her center. In this phase evolutional to
development and it must not be observed considerable
change of amplitude (color index). The light curves,
effective temperature and luminosity of V1033 Cyg
are consistent with fundamental mode pulsation for a
classical Cepheid on the center of the instability strip.