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2S 1553-542: a Be/X-ray binary pulsar on the far side of the Galaxy
Monthly Notices of the Royal Astronomical Society. 2016. Vol. 462. No. 4. P. 3823–3829.
Lutovinov A.
We report the results of a comprehensive analysis of X-ray (Chandra and Swift observatories), optical (Southern African Large Telescope, SALT) and near-infrared (the VVV survey) observations of the Be/X-ray binary pulsar 2S 1553-542. Accurate coordinates for the X-ray source are determined and are used to identify the faint optical/infrared counterpart for the first time. Using VVV and SALTICAM photometry, we have constructed the spectral energy distribution (SED) for this star and found a moderate NIR excess that is typical for Be stars and arises due to the presence of circumstellar material (disc). A comparison of the SED with those of known Be/X-ray binaries has allowed us to estimate the spectral type of the companion star as B1-2V and the distance to the system as >15 kpc. This distance estimation is supported by the X-ray data and makes 2S 1553-542 one of the most distant X-ray binaries within the Milky Way, residing on the far side in the Scutum-Centaurus arm or even further.
Sazonov S., Experimental Astronomy 2019 Vol. 48 No. 2-3 P. 233–244
We have performed tests of the SRG project's ART-XC telescope's flight spare units of the mirror system (MS) and the URD focal plane X-ray detector. During the tests, the MS was illuminated by a quasi-parallel X-ray beam from a microfocus tube. By changing the angle between the MS optical axis and the incoming beam we ...
Added: August 6, 2020
Sazonov S., Experimental Astronomy 2019 Vol. 47 No. 1-2 P. 1–27
We have performed calibration tests of a spare CdTe detector unit of the ART-XC/SRG telescope at the Space Research Institute's 60-m-long X-ray test facility. During the tests, we illuminated the detector with a quasi-parallel X-ray beam generated by interchangeable X-ray tubes with different targets. To monitor the X-ray flux, we used two commercial detectors Amptek ...
Added: February 1, 2019
Sazonov S., Experimental Astronomy 2018 Vol. 45 No. 3 P. 315–350
From October 2016 to September 2017, we performed tests of the ART-XC /SRG spare mirror system and detector unit at the 60-m-long IKI X-ray test facility. We describe some technical features of this test facility. We also present a brief description of the ART-XC mirror system and focal detectors. The nominal focal length of the ...
Added: February 1, 2019
Lutovinov A., Monthly Notices of the Royal Astronomical Society 2017 Vol. 464 No. 2 P. 2039–2045
In this paper, we investigated the long-term evolution of the pulse period in the high-mass X-ray binary LMC X-4 by taking advantage of more than 43 yr of measurements in the X-ray domain. Our analysis revealed for the first time that the source is displaying near-periodical variations of its spin period on a time-scale of ...
Added: January 16, 2018
Lutovinov A., Monthly Notices of the Royal Astronomical Society 2017 Vol. 466 No. 1 P. 593–599
We report on the first focused hard X-ray view of the absorbed supergiant system IGR J18027-2016 performed with the Nuclear Spectroscopic Telescope Array observatory. The pulsations are clearly detected with a period of Pspin = 139.866(1) s and a pulse fraction of about 50-60 per cent at energies from 3 to 80 keV. The source ...
Added: January 16, 2018
Sazonov S., Khabibullin I., Medvedev P., Monthly Notices of the Royal Astronomical Society 2016 Vol. 455 No. 2 P. 1414–1427
We present a publicly available spectral model for thermal X-ray emission from a baryonic jet in an X-ray binary system, inspired by the microquasar SS 433. The jet is assumed to be strongly collimated (half-opening angle Θ ˜ 1°) and mildly relativistic (bulk velocity β = Vb/c ˜ 0.03-0.3). Its X-ray spectrum is found by ...
Added: December 26, 2017
Sazonov S., Khabibullin I., Monthly Notices of the Royal Astronomical Society 2016 Vol. 457 No. 4 P. 3963–3974
We evaluate the emission that must arise due to reflection of the putative collimated X-ray radiation of SS 433 by atomic gas and molecular clouds in the Galactic plane and compare the predicted signal with existing RXTE and ASCA data for the region of interest. Assuming that the intrinsic X-ray spectrum of SS 433 is ...
Added: December 26, 2017
Sazonov S., Monthly Notices of the Royal Astronomical Society 2016 Vol. 459 No. 1 P. 140–150
We present results of a deep survey of three extragalactic fields, M81 (exposure of 9.7 Ms), Large Magellanic Cloud (6.8 Ms) and 3C 273/Coma (9.3 Ms), in the hard X-ray (17-60 keV) energy band with the IBIS telescope onboard the INTEGRAL observatory, based on 12 years of observations (2003-2015). The combined survey reaches a 4σ ...
Added: December 26, 2017
Sazonov S., Medvedev P., Gilfanov M., Monthly Notices of the Royal Astronomical Society 2016 Vol. 459 No. 1 P. 431–440
We investigate the possible impact of diffusion on the abundance of helium and other primordial elements during formation of the first structures in the early Universe. We consider the primary collapse of a perturbation and subsequent accretion of matter on to the virialized halo, restricting our consideration to haloes with masses considerably above the Jeans ...
Added: December 26, 2017
Sazonov S., Krivonos R., Monthly Notices of the Royal Astronomical Society 2016 Vol. 463 P. 756–762
We present a high-quality hard X-ray spectrum of the ultraluminous X-ray source (ULX) NGC 5643 X-1 measured with NuSTAR in 2014 May-June. We have obtained this spectrum by carefully separating the signals from the ULX and from the active nucleus of its host galaxyNGC 5643 located 0.8 arcmin away. Together with long XMM-Newton observations performed ...
Added: December 26, 2017
Sazonov S., Monthly Notices of the Royal Astronomical Society 2017 Vol. 466 No. 1 P. 1019–1051
Using a spectral analysis of bright Chandra X-ray sources located in 27 nearby galaxies and maps of star-formation rate (SFR) and interstellar medium surface densities for these galaxies, we constructed the intrinsic X-ray luminosity function (XLF) of luminous high-mass X-ray binaries (HMXBs), taking into account absorption effects and the diversity of HMXB spectra. The XLF ...
Added: December 26, 2017
Sazonov S., Khabibullin I., Monthly Notices of the Royal Astronomical Society 2017 Vol. 468 No. 2 P. 2249–2255
Using a sample of 200 luminous (LX, unabs > 1038 erg s-1, where LX, unabs is the unabsorbed 0.25-8 keV luminosity) high-mass X-ray binary (HMXB) candidates found with Chandra in 27 nearby galaxies, we have constructed the collective X-ray spectrum of HMXBs in the local Universe per unit star formation rate, corrected for observational biases associated with intrinsic ...
Added: December 26, 2017
Sazonov S., Lutovinov A., Monthly Notices of the Royal Astronomical Society 2017 Vol. 470 No. 1 P. 512–516
The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) continues to successfully work in orbit after its launch in 2002. The mission provides the deepest ever survey of hard X-ray sources throughout the Galaxy at energies above 20 keV. We report on a catalogue of new hard X-ray source candidates based on the latest sky maps comprising 14 ...
Added: December 26, 2017
Буренин Р. А., Sazonov S., Experimental Astronomy 2017 Vol. 44 No. 1 P. 147–164
The Astronomical Röntgen Telescope X-ray Concentrator (ART-XC) is a hard X-ray telescope with energy response up to 30 keV, to be launched on board the Spectrum Röntgen Gamma (SRG) spacecraft in 2018. ART-XC consists of seven identical co-aligned mirror modules. Each mirror assembly is coupled with a CdTe double-sided strip (DSS) focal-plane detector. Eight X-ray ...
Added: December 26, 2017