Zobrazeno 1 - 10
of 39
pro vyhledávání: '"O. Alksnis"'
Autor:
L. Zacs, O. Alksnis
Publikováno v:
Odessa Astronomical Publications, Vol 18, Iss 0, Pp 144-145 (2017)
The first results of detailed spectroscopy are presented for carbon Mira R Leporis. This long-period variable is undergoing deep fadings, apparently caused by dust formation around the star. High-resolution CCD spectra were observed for two seasons.
Externí odkaz:
https://doaj.org/article/b3fd8b86cf0249bc94a5f5a04bb05bc9
Publikováno v:
Astrophysics and Space Science. 365
The mass of the cool carbon star HD 54361 was suspected to be high, assuming the membership in the stellar association CMa OB1, in conflict with the theory of stellar evolution. The Gaia parallax and a high-resolution spectrum in the wavelength regio
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 417:649-658
The results of local thermodynamic equilibrium (LTE) abundance analysis are presented for four red giants in the fields of open clusters NGC 1545 and Tr2. The membership of HD 27276, HD 27292 and HD 16068 was confirmed and the age of NGC 1545 was upd
Publikováno v:
Astronomy & Astrophysics. 472:247-256
Context. Theoretically, the number of cool Galactic R Coronae Borealis stars (RCBs) should be greater than the warm RCBs, however to date, only a few candidates have been detected. Aims. Observations of the extremely cool RCB candidate, DY Per, and t
Autor:
H. T. Lee, F. A. Musaev, C. W. Chen, T. Brice, Kaushar Sanchawala, Wen Ping Chen, O. Alksnis, L. Začs, Daisuke Kinoshita
Publikováno v:
Astronomy & Astrophysics. 438:L13-L16
Results of first CCD photometry during the recent deep light decline, and high-resolution spectroscopy, are presented for DY Persei. The spectra show variable blueshifted features in the sodium D lines. The C lines are strong whereas neutron- cap
Autor:
O. Alksnis, L. Začs
Publikováno v:
Astrophysics and Space Science. 215:73-82
Moderate dispersion (25-35 A mm−1) spectra were obtained from two carbon stars, V Cyg and WZ Cas, in a wide range of wavelengths (λλ3400-6800 A) with the echelle-spectrometer, ZEBRA, of the 6 m telescope and two-dimensional photon-counting system
Autor:
O. Alksnis, L. Zacs
Publikováno v:
Astrophysics and Space Science. 207:183-195
Publikováno v:
AIP Conference Proceedings.
The spectroscopy of two carbon‐rich mass‐loosing variables—R Leporis and DY Persei ‐is presented. High‐resolution echelle spectra of carbon Mira R Lep were observed for two seasons. The heliocentric photospheric radial velocity was found to
Publikováno v:
Proceedings of the International Astronomical Union. 1:281-282
The preliminary results of abundance analysis are presented for extremely metal-poor carbon star HD 112869 = TT CVn = CGCS 3319. The radial velocity was found to be −137.7 km s −1 . Our LTE abundance analysis supports an extremely low metallicity
Publikováno v:
Astronomy and Astrophysics Supplement Series. 136:453-454
High{resolution spectroscopic observations are presented for 19 single{lined binaries (giants and dwarfs) with orbital elements and mass functions similar to those of barium stars, two radial velocity non{variable barium stars, and two standards. All