Publications (14)
Doppler confirmation of TESS planet candidate TOI1408.01: grazing transit and likely eccentric orbit
G. A. Galazutdinov, R. V. Baluev, G. Valyavin +16
We report an independent Doppler confirmation of the TESS planet candidate orbiting an F-type main sequence star TOI-1408 located 140 pc away. We present a set of radial velocities…
Magnetic field and radial velocities of the star Chi Draconis A
Byeong-Cheol Lee, D. Gadelshin, Inwoo Han +13
We present high-resolution spectropolarimetric observations of the spectroscopic binary Chi Dra. Spectral lines in the spectrum of the main component Chi Dra A show variable Zeeman…
Search for LBVs in the Local Volume galaxies: study of four stars in NGC 4449
Y. Solovyeva, A. Vinokurov, A. Sarkisyan +8
We continue to search for LBV stars in galaxies outside the Local Group. In this work, we have investigated four luminous stars in NGC 4449. Multiple spectral observations carried…
Luminous Blue Variable candidates in M31
A. Sarkisyan, O. Sholukhova, S. Fabrika +7
We study five Luminous Blue Variable (LBV) candidates in the Andromeda galaxy and one more (MN112) in the Milky Way. We obtain the same-epoch near-infrared (NIR) and optical spectr…
Optical counterparts of two ULXs in NGC5474 and NGC3627 (M66)
S. Avdan, A. Vinokurov, S. Fabrika +6
We identified two optical counterparts of brightest ultraluminous X-ray Sources (ULXs) in galaxies NGC5474 and NGC3627 (M66). The counterparts in Hubble Space Telescope images are…
Photometric and spectroscopic analysis of LBV candidate J004341.84+411112.0 in M31
A. Sarkisyan, O. Sholukhova, S. Fabrika +4
We study Luminous Blue Variable (LBV) candidate J004341.84+411112.0 in the Andromeda galaxy. We present optical spectra of the object obtained with the 6-m telescope of SAO RAS. Th…
A detailed time-resolved and energy-resolved spectro-polarimetric study of bright GRBs detected by AstroSat CZTI in its first year of operation
Rahul Gupta, S. B. Pandey, S. Gupta +11
The radiation mechanism underlying the prompt emission remains unresolved and can be resolved using a systematic and uniform time-resolved spectro-polarimetric study. In this paper…
Search for LBVs in the Local Volume galaxies: study of two stars in NGC 1156
Y. Solovyeva, A. Vinokurov, N. Tikhonov +7
We continue the search for luminous blue variables (LBVs) in Local Volume galaxies in order to study their fundamental parameters. In this paper, we report the discovery of two new…
New Luminous Blue Variables in the Andromeda galaxy
O. Sholukhova, D. Bizyaev, S. Fabrika +3
We performed spectroscopy of five Luminous Blue Variable (LBV) candidates and two known LBV stars (AE And and Var A-1) in M31. We obtained the same-epoch near-infrared (NIR) and op…
High-redshift GRB 140304A at z = 5.282 with flaring activity: A multi-wavelength study
Shashi. B. Pandey, Amit. K. Ror, A. J. Castro-Tirado +48
Context. This article presents a detailed multi-wavelength analysis of GRB 140304A at z = 5.282, having uncommon late-time flaring features. The aim is to study GRB 140304A and oth…
Fast spectral variations of OBA stars
A. F. Kholtygin, S. Hubrig, V. V. Dushin +4
Our search for magnetic fields in selected OBA stars using FOcal Reducer low dispersion Spectrographs FORS 1 and FORS 2 in spectropolarimetric mode revealed the presence of strong…
New data for the LBV in NGC 4736
Y. Solovyeva, A. Vinokurov, A. Kostenkov +3
We present new spectral and photometric data of confirmed LBV star from the NGC4736 galaxy. The star NGC4736_1 (Mbol = -11.5 mag) showed noticeable spectral variability from 2015 t…
New Luminous Blue Variable Candidates in NGC 4736
Y. Solovyeva, A. Vinokurov, S. Fabrika +8
We have found three new LBV candidates in the star-forming galaxy NGC 4736. They show typical well-known LBV spectra, broad and strong hydrogen lines, He I lines, many Fe II lines,…
Optical Identification of Four Hard X-ray Sources from the Swift All-Sky Survey
A. Lutovinov, R. Burenin, M. Revnivtsev +3
We present the results of our optical identifications of four hard X-ray sources from the Swift all-sky survey. We obtained optical spectra for each of the program objects with the…