Zobrazeno 1 - 10
of 680
pro vyhledávání: '"Andrievsky, S. M."'
The purpose of this work is to spectroscopically analyse the classical Cepheid V708 Car. A preliminary check of the spectrum of V708 Car showed that this is a lithium-rich supergiant. We also found that V708 Car has an unusual chemical composition in
Externí odkaz:
http://arxiv.org/abs/2402.13072
While looking for recently discovered distant Cepheids with an interesting chemical composition, we noticed one star (OGLE GD-CEP-1353) with extremely large equivalent widths of spectral lines of heavy elements. The aim of this work is to perform an
Externí odkaz:
http://arxiv.org/abs/2310.10381
We have searched for lines of the radioactive element technetium (Tc) in the spectrum of Przybylski's star (HD101065). The nuclei of this chemical element are formed in the slow process of capturing thermalized neutrons. The possible lines of Tc~I ar
Externí odkaz:
http://arxiv.org/abs/2308.04479
Comet 29P/Schwassmann-Wachmann 1 dust environment from photometric observation at the SOAR Telescope
Autor:
Picazzio, E., Luk'yanyk, I. V., Ivanova, O. V., Zubko, E., Cavichia, O., Videen, G., Andrievsky, S. M.
We report photometric observations of comet 29P/Schwassmann-Wachmann 1 made on August 12, 2016 with the broadband B, V, R and I filters and the SOAR 4.1-meter telescope (Chile). We find the comet active at that time. Enhanced images obtained in all f
Externí odkaz:
http://arxiv.org/abs/2012.10718
Autor:
Ivanova, O. V., Luk'yanyk, I. V., Kiselev, N. N., Afanasiev, V. L., Picazzi, E., Cavichia, O., de Almeida, A. A., Andrievsky, S. M.
We carried out photometric and spectroscopic observations of comet 29P/Schwassmann-Wachmann 1 at the 6-m BTA telescope (SAO RAS, Russia) and the 1.6-m telescope of the National Laboratory for Astro-physics (LNA, Brazil) on February 20, 2012, and on M
Externí odkaz:
http://arxiv.org/abs/2012.10705
We present a study of departures from Local Thermodynamic Equilibrium (LTE) in the formation of infra-red lines of Na I, Mg I, Al I, S I, K I and Sr II in unevolved stars of spectral types F,G,K and metallicities around the solar metallicity. The pur
Externí odkaz:
http://arxiv.org/abs/2006.10998
Autor:
Kovtyukh, V. V., Andrievsky, S. M., Martin, R. P., Korotin, S. A., Lepine, J. R. D., Maciel, W. J., , L. E Keir, Panko, E. A.
We have made the first attempt to derive the chemical properties of the Galactic disc at its very central part using high-resolution infrared spectroscopic observations of four classical Cepheids. Those stars are located at Galactocentric distances s
Externí odkaz:
http://arxiv.org/abs/1909.00662
We checked consistency between the copper abundance derived in six metal-poor stars using UV Cu II lines (which are assumed to form in LTE) and UV Cu I lines (treated in NLTE). Our program stars cover the atmosphere parameters which are typical for i
Externí odkaz:
http://arxiv.org/abs/1807.08972
We revisited barium abundance in a sample of giant stars in the dwarf spheroidal Fornax galaxy. Non-local thermodynamic equilibrium (NLTE) synthesis was used to derive the barium abundance from two Ba II lines. Our new NLTE result for barium shows th
Externí odkaz:
http://arxiv.org/abs/1710.04930
We have derived the abundances of 36 chemical elements in one Cepheid star, ASAS 181024--2049.6, located R$_{\rm G}= 2.53$ kpc from the Galactic center. This star falls within a region of the inner thin disc poorly sampled in Cepheids. Our spectral a
Externí odkaz:
http://arxiv.org/abs/1607.00129