SPECTROSCOPICAL STUDY OF FAINT SOUTHERN CEPHEIDS WITH SOUTHERN AFRICAN LARGE TELESCOPE (SALT). FIRST RESULTS.
Journal Title: Odessa Astronomical Publications - Year 2017, Vol 30, Issue
Abstract
First Cepheids observations using echelle-spectrograph HRS fed by Southern African Large Telescope (SALT) were realized during 2016. All spectra have been obtained in the medium resoltion mode (R≈31000–41000) wth high S/N ratio near 50–220. All data were processed using package developed by authors based on the standard system of astronomical data reduction MIDAS. Using new echelle data we found the atmosphere parameters and chemical composition for 30 faint Cepheids of southern hemisphere, where for the most of theses stars these results we obtained for the first time. 28 stars are Cepheids after the first-dredge up stage, while ASAS 075842-25336.1 and ASAS 1131714-6605.0 having remarkable Li I 6707.8 Å absorption line and anomalous CNO and Na content could be consider as first crossing of the Cepheids instability strip.
Authors and Affiliations
I. A. Usenko, A. Yu. Kniazev, V. V. Kovtyukh, S. I. Belik, L. N. Berdnikov
Keywords
Related Articles
- EP ID EP349431
- DOI 10.18524/1810-4215.2017.30.117156
- Views 92
- Downloads 0
SOFTWARE FOR PROCESSING OF DIGITIZED ASTRONEGATIVES FROM ARCHIVES AND DATABASES OF VIRTUAL OBSERVATORY
The paper discusses and illustrates the steps of basic processing of digitized image of astro negatives. Software for obtaining of a rectangular coordinates and photometric values of objects on photographic plates w...
ASTROMETRY OF Χ AND H PERSEI BASED ON PROCESSING OF DIGITIZED PLATES OF ARCHIVE OF THE ASTRONOMICAL INSTITUTE OF THE ACADEMY OF SCIENCES OF THE REPUBLIC OF UZBEKISTAN
Work is done with Epson Expression 10000XL scanner of Astronomical Institute (AI) of the Academy of Sciences of Uzbekistan. The plates were exposed with the Normal astrograph (D/F = 330mm / 3467mm, M = 59.56"/mm)....
RESULTS OF PROCESSING OF CCD OBSERVATIONS OF SELECTED OPEN CLUSTERS ON MAIDANAK
Observations of 20 open clusters at the Maidanak Observatory were performed using the Zeiss-1000 telescope in the winter of 2018. As the light receiver, a CCD camera Apogee Alta U9000 (3K x 3K, FOV 19.5'x19.5') was used....
PHASE PLANE ANALYSIS OF THE PHOTOMETRICAL VARIATIONS OF LONG-PERIOD VARIABLES
Using the phase plane diagrams, the phase light curves of a group of the Mira-type stars and semi-regular variables are analyzed. As generalized coordinates х and ẋ, we have used m – the brightne...
ANALYSIS OF SELF – GRAVITATING PLANETARY SATELLITES IN THE SOLAR SYSTEM
As of today there have been more than 180 planetary satellites discovered in the Solar system, and the number of outer moons found continues to grow. Most of those natural satellites have insufficient mass and are able t...