ABSTRACT We present a catalogue of point sources detected with the Mikhail Pavlinsky ART-XC telescope onboard the SRG observatory during a wide-field survey of the Galactic Bulge that was conducted as part of the mission’s calibration and performance verification phase in 2019. The survey consisted of nearly 18 d of consecutive scanning observations of the sky region |l| < 6 deg, |b| < 2.5 deg with the median sensitivity of 4 × 10−13 erg s−1 cm−2 in the 4–12 keV energy band, which allows the detection of sources down to a luminosity of 3 × 1033 erg s−1 near the Galactic Centre. Using a maximum-likelihood-based algorithm, 172 sources were detected. Of these, 153 are registered on the average 4–12 keV map and 18 sources are either extremely hard (detected only at energies above 7 keV) or highly variable (detected only in individual scans shorter than a day). For 121 sources, there are plausible counterparts in other X-ray source catalogues, including 43 with known classification. The remaining 51 sources are previously unknown objects, discovered by ART-XC during the Galactic Bulge survey.

We present an updated catalog of sources detected by the Mikhail Pavlinsky ART-XC telescope aboard the Spektrum-Roentgen-Gamma (SRG) observatory during its all-sky survey. It is based on the data of the first four and the partially completed fifth scans of the sky (ARTSS1-5). The catalog comprises 1545 sources detected in the 4-12 keV energy band. The achieved sensitivity ranges between similar to 4 x 10(-1)2 erg s(-1) cm(-2) near the ecliptic plane and similar to 7 x 10(-13) erg s(-1) cm(-2) near the ecliptic poles, which is a similar to 30-50% improvement over the previous version of the catalog based on the first two all-sky scans (ARTSS12). There are similar to 130 objects, excluding the expected contribution of spurious detections, that were not known as X-ray sources before the SRG/ART-XC all-sky survey. We provide information, partly based on our ongoing follow-up optical spectroscopy program, on the identification and classification of the majority of the ARTSS1-5 sources (1463), of which 173 are tentative at the moment. The majority of the classified objects (964) are extragalactic, a small fraction (30) are located in the Local Group of galaxies, and 469 are Galactic. The dominant classes of objects in the catalog are active galactic nuclei (911) and cataclysmic variables (192).

ART-XC (Astronomical Roentgen Telescope - X-ray Concentrator) is the hard X-ray instrument with grazing incidence imaging optics on board the Spektr-Roentgen-Gamma (SRG) observatory. The SRG observatory is the flagship astrophysical mission of the Russian Federal Space Program, which was successively launched into orbit around the second Lagrangian point (L2) of the Earth-Sun system with a Proton rocket from the Baikonur cosmodrome on 13 July 2019. The ART-XC telescope will provide the first ever true imaging all-sky survey performed with grazing incidence optics in the 4-30 keV energy band and will obtain the deepest and sharpest map of the sky in the energy range of 4-12 keV. Observations performed during the early calibration and performance verification phase as well as during the on-going all-sky survey that started on 12 Dec. 2019 have demonstrated that the in-flight characteristics of the ART-XC telescope are very close to expectations based on the results of ground calibrations. Upon completion of its 4-year all-sky survey, ART-XC is expected to detect 5000 sources ( 3000 active galactic nuclei, including heavily obscured ones, several hundred clusters of galaxies, 1000 cataclysmic variables and other Galactic sources), and to provide a high-quality map of the Galactic background emission in the 4-12 keV energy band. ART-XC is also well suited for discovering transient X-ray sources. In this paper, we describe the telescope, results of its ground calibrations, major aspects of the mission, the in-flight performance of ART-XC and first scientific results.

Spectrum Roentgen Gamma (SRG) is an X-ray astrophysical observatory, developed by Russia in collaboration with Germany. The mission will be launched in 2013 from Baikonur, by a Zenit rocket with a Fregat booster and placed in a 6-month-period halo orbit around L2. The scientific payload consists of two independent telescopes - a soft-x-ray survey instrument, eROSITA, being provided by Germany and a medium-x-ray-energy survey instrument ART-XC being developed by Russia. ART-XC will consist of seven independent, but co-aligned, telescope modules with seven corresponding cadmiumtelluride focal plane detectors. Each will operate over the approximate energy range of 6-30 keV, with an angular resolution of 1 arcmin, a field of view of ~30 arcmin and an energy resolution about 10% at 14 keV. The NASA Marshall Space Flight Center (MSFC) will fabricate some of the mirror modules, to complement others fabricated by VNIIEF in Russia.

The Spectrum-Roentgen-Gamma mission will be launched in the 2012 year into a L2 orbit with Soyuz launcher and Fregat buster from Baikonur. The mission will conduct all-sky survey with X-ray mirror telescopes eROSITA and ART-XC up to 11 keV. It will allow detection of about 100 thousand clusters of galaxies and discovery large scale Universe structure. It will also discover all obscured accreting Black Holes in nearby galaxies and many (about 3 millions) new distant AGN. Then it is planned to observe dedicated sky regions with high sensitivity and thereafter to perform follow-up pointed observations of selected sources.

The ART-XC instrument is an X-ray grazing-incidence telescope system in an ABRIXAS-type optical configuration optimized for the survey observational mode of the Spectrum-RG astrophysical mission which is scheduled to be launched in 2011. ART-XC has two units, each equipped with four identical X-ray multi-shell mirror modules. The optical axes of the individual mirror modules are not parallel but are separated by several degrees to permit the four modules to share a single CCD focal plane detector, 1/4 of the area each. The 450-micron-thick pnCCD (similar to the adjacent eROSITA telescope detector) will allow the detection of X-ray photons up to 15 keV. The field of view of the individual mirror module is about 18×18 arcminutes2 and the sensitivity of the ART-XC system for 4 years of survey will be better than 10-12 erg s-1 cm-2 over the 4-12 keV energy band. This will allow the ART-XC instrument to discover several thousands new AGNs.

Summary form only given. Since 2000 year LUCH laser facility has been worked at RFNC-VNIIEF. This facility was designed as prototype of ISKRA-6 128-beams facility that is developing now. Basis of LUCH facility is 4-beams Nd-glass laser with operating aperture 20times20 cm. This laser is included two four-path amplifiers that are pumped by 432 xenon flashlamps. The capacitor bank with near 5MJ stored energy at operating voltage of 24 kV has been constructed to drive amplifiers flashlamps. 18 unified modules are included in the bank. Each single module is discharged to lamp load by semiconductor closing switch based on reverse switched dynistors. Description of module components and bank subsystems such as charging, triggering, control and diagnostic is presented in this report. Also the bank performance during the exploitation is discussed.

Summary form only given. The ISKRA-6 laser is a 128-beam, flashlamp-driven neodymium-glass laser that will produce near 0.6 MJ of light on target. Each of the 128 beams of the ISKRA-6 laser is amplified in two four-pass laser amplifiers. Pumping system of these amplifiers is consisted the 5120 xenon flash lamps that are drove by a power conditioning system. ISKRA-6 power conditioning system (PCS) is based on the capacitor storage bank to deliver approximately 35 k.F to each of 5120 flashlamps. So, PCS will be capable of storing nearly 215 MJ of electrical energy at 24 kV The capacitor bank will include the 256 unified modules. This paper describes the design of module and results of testing of module prototype. It also discusses the components of module including self-healing capacitors, main semiconductor closing switches based on reverse switched dynistors, and other components.

The hard X-ray telescope-concentrator ART-XC on board the Spectrum-X-Gamma X-ray astrophysical observatory (launching in 2011) is one of the main instruments of the mission. The instrument will be used for an all-sky survey and then for pointed observations which are planned for the first four and the next three years of the Mission, respectively. ART-XC will be sensitive in the 4-30 keV energy range and will have an effective area of several hundred square centimeters at 10 keV. It will have a field of view of about ~28 arcmin, angular resolution better than 1 arcmin and will be an order of magnitude more sensitive than the current generation of collimated instruments and coded mask telescopes in the survey mode and a two or three orders of magnitude more sensitive in the pointing mode. With its high sensitivity in the hard X-ray band and good imaging capabilities, ART-XC will extend the operating energy range of the observatory (complementing the capabilities of the primary science instrument eROSITA), thus significantly enhancing the mission both in the all-sky survey over the energy band 4-10 keV and, especially, in pointed observations over the energy band 4-30 keV. During the 4-year survey, this ART-XC would detect more than ~104 sources over 4-10 keV. For a 105 second pointed observation, the telescope will provide better than 10 microCrab sensitivity in the 4-20 keV energy range.

Summary form only given. A new generation of semiconductor closing switches based on reverse switched dynistors (RSD) has been developed to switch high-power current pulses with microsecond duration. In this report the results of theoretical and experimental investigations of RSD at peak current more than 500 kA and pulse duration up to 500 mus (at 0.1 Imax) are observed. The criteria of extreme peak current for switch taking into consideration the longtime performance under pulse-periodical mode are gave. The design and test results for switch under single pulse mode at operating voltage up to 25 kV and peak current up to 300 kA are described. The possibility of using such a switch in the ISKRA-6 capacitor bank is estimated.