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10:00	0:40	Prof. Andrei Bykov Prof. Andrei Bykov Ioffe Institute	Galactic Accelerators of Very High Energy Particles: their X-ray and Gamma-ray appearance
Significantly improved sensitivity of ground-based Cherenkov gamma-ray telescopes being combined with X-ray observations have made it possible to obtain unique information about the extreme processes of very high energy particle acceleration in galactic and extragalactic sources. We discuss the results of multi-wavelength observations and theoretical models of supernova remnants, pulsar wind nebulae, binary stars with relativistic companions, and clusters of young massive stars as sources of very high energy cosmic rays. Of a particular interest is the use X-ray polarimetry data to look into particle acceleration process in fast outflows of the powerful sources. Recent gamma-ray observations demonstrated that the accreting stellar mass black holes and young pulsars in binary star systems — galactic microquasars — can accelerate electrons to energies about PeV and the ions above the energies. Efficient mechanisms of particle acceleration in the Pevatrons are discussed.
10:00	0:40	Prof. Andrei Bykov Prof. Andrei Bykov Ioffe Institute
Galactic Accelerators of Very High Energy Particles: their X-ray and Gamma-ray appearance

10:40	0:40	Prof. Zhen Cao Prof. Zhen Cao Institute of High Energy Physics	Microquasars Found as PeV Cosmic Ray Accelerators by LHAASO
LHAASO found that UHE photons are emitted from 5 MQs out of 12 of them in the FoV of LHAASO. This clearly demonstrates that a new CR source population is uncovered including a super-PeVatron and a perfect BH+jet system, SS433, permitting deep investigations of the accretion disk, jets, outflow etc. It is found that only a order of 10 of those sources would be sufficient to supply the flux of CRs around the knee. Further detailed investigations will be carried out using future instruments
10:40	0:40	Prof. Zhen Cao Prof. Zhen Cao Institute of High Energy Physics
Microquasars Found as PeV Cosmic Ray Accelerators by LHAASO

11:20	0:30	Coffee Break

11:50	0:20	Eugene Zakharov Eugene Zakharov IKI	X-ray constraints on keV-scale Sterile Neutrino Dark Matter from SRG/ART-XC and NuSTAR observations
We present observational constraints on keV-scale sterile neutrino dark matter based on archival X-ray data from two complementary instruments: SRG/ART-XC and NuSTAR. Sterile neutrinos with masses of a few to several tens of keV are well-motivated dark matter candidates, expected to decay radiatively into an active neutrino and a photon with energy $E_\gamma = m_s/2$.We search for such decay signatures in the Milky Way halo by analyzing the unresolved X-ray emission in two independent data sets: the all-sky survey from ART-XC in the 6-20 keV range, and the unfocused stray-light background from NuSTAR in the 3-20 keV range. No significant line-like excess is detected. The NuSTAR data, with high exposure and sensitivity, allow us to place exceptionally strong constraints, excluding the entire viable parameter space for sterile neutrinos with masses of a few keV. While the ART-XC limits are less stringent, they are based on a uniform all-sky coverage and a more direct observational strategy, reducing certain systematic uncertainties. Together, these results provide robust and complementary bounds on the parameter space of radiatively decaying dark matter, probing down to the lower edge of predictions in minimal extensions of the Standard Model, including the $\nu$MSM.
11:50	0:20	Eugene Zakharov Eugene Zakharov IKI
X-ray constraints on keV-scale Sterile Neutrino Dark Matter from SRG/ART-XC and NuSTAR observations

12:10	0:20	Mikhail Belvedersky Mikhail Belvedersky IKI	Reflection-dominated Compton-thick AGN Candidates in the SRG/eROSITA Lockman Hole Survey
We found candidates to reflection-dominated Compton-thick active galactic nuclei (CT AGN) in the Lockman Hole region using the SRG/eROSITA Lockman Hole survey data. Selected sources have anomalously hard photon indexes in the 0.3 — 8.0 keV band, which differ from typical Type I AGN values. We required that the upper end of the 90% error interval did not exceed a fiducial boundary of $\Gamma = 1.3$. This selection yielded 291 sources which constitute a rare subpopulation among extragalactic X-ray sources detected by eROSITA in the Lockman Hole field, approximately 5%. These sources constitute the eROSITA sample of CT AGN candidates in the Lockman Hole field. We divided these sources into three categories based on reliable redshift availability and statistically significant detection of the intrinsic absorption. We present two catalogues: a bright subsample (37 sources) and a faint subsample (254). We show examples of individual spectra and use stacking analysis to search for possible redshift evolution of their properties with redshift. We conducted a detailed analysis of one selected source that has clear signs of the relativistically broadened FeK$\alpha$ line in its X-ray spectra. The CT AGN candidate catalogues will facilitate future observational studies and follow-up investigations.
12:10	0:20	Mikhail Belvedersky Mikhail Belvedersky IKI
Reflection-dominated Compton-thick AGN Candidates in the SRG/eROSITA Lockman Hole Survey

12:30	0:40	Prof. Zhaosheng Li Prof. Zhaosheng Li Xiangtan University	Broadband X-ray spectral and timing properties of accreting millisecond X-ray pulsars
I will report recent progress of broadband spectral and timing properties of accreting millisecond X-ray pulsars.
12:30	0:40	Prof. Zhaosheng Li Prof. Zhaosheng Li Xiangtan University
Broadband X-ray spectral and timing properties of accreting millisecond X-ray pulsars

13:10	1:30	Lunch

14:40	0:40	Prof. Konstantin Postnov Prof. Konstantin Postnov Sternberg Astronomical Institute, Moscow University	Caucasian Mountain Observatory of Moscow State University: Status and Prospects
We the current status and some observational results of Caucasian Mountain Observatory (CMO) run by Sternberg Astronomical Institute at Northern Caucasus. The principal instrument is a 2.5-m Ritchey-Chretien telescope operated since 2014, equipped with photometric and spectroscopic facilities in the optical and near IR bands. The observatory is participating in several international programs, including the optical and IR support of SRG/eROSITA mission, photometric observations of TESS exoplanet transits, new supernova spectral and photometric monitoring, etc. We briefly present some results obtained with CMO telescopes (long-term photometric and spectral monitoring of SS433, X-ray novae in low states, multicolor mapping of galaxies, etc.), and discuss future plans of development of CMO equipment (high-resolution spectroscopy) and new projects, including possible radio monitoring of Sun in the frame of ICMP Meridian program and lunar radar ranging.
14:40	0:40	Prof. Konstantin Postnov Prof. Konstantin Postnov Sternberg Astronomical Institute, Moscow University
Caucasian Mountain Observatory of Moscow State University: Status and Prospects

15:20	0:30	Prof. Sergey Sazonov Prof. Sergey Sazonov IKI	SRG/ART-XC all-sky X-ray survey: Catalog of sources
We have recently released a catalog of sources detected by the SRG/ART-XC telescope during its first five all-sky surveys (ARTSS1-5). It comprises 1545 sources detected in the 4-12 keV energy band, including 130 that were not known as X-ray sources before. I will discuss the on-going efforts to maximise the scientific outcome of this new X-ray source database, with a focus on active galactic nuclei, and outline the prospects for its extension using new data from the SRG/ART-XC all-sky survey.
15:20	0:30	Prof. Sergey Sazonov Prof. Sergey Sazonov IKI
SRG/ART-XC all-sky X-ray survey: Catalog of sources

15:50	0:30	Dr. Sergey Molkov Dr. Sergey Molkov IKI	Fast timing with the ART-XC/SRG telescope
In the talk we will present a brief overview of observations of rapidly rotating neutron stars by Mikhail Pavlinsky ART-XC telescope installed on-board of Spektrum-Rentgen Gamma observatory. Despite the fact that the telescope was designed for scanning large areas of the celestial sphere, its temporal characteristics and sensitivity flux sensitivity allow for fine timing analysis of coherent signals with millisecond periods. We will highlight some results of observations of both isolated rapidly rotating neutron stars and accreting millisecond pulsars.
15:50	0:30	Dr. Sergey Molkov Dr. Sergey Molkov IKI
Fast timing with the ART-XC/SRG telescope

16:20	0:30	Coffee Break

16:50	0:30	Dr. Andrey Semena Dr. Andrey Semena IKI	ART-XC large scale deep surveys
Mikhail Pavlinskiy’s ART-XC hard X-ray telescope was designed to conduct all sky survey with a mission to complement co-aligned soft X-ray eRosita telescope and pick-up overlooked highly obscured and extremely hard sources. It also was realized that the telescope with its survey capabilities, hard X-ray band and compact PSF can provide beneficiary coverage of the Galactic fields. In particular the telescope is well suited to search for highly obscured and transient sources in the overcrowded Galactic regions. In order to perform such surveys we developed a likelihood based source detection approach which allows to exclude an illumination from bright sources and account for sources spectra in completeness estimations. In this talk I will discuss our strategy in conducting such surveys and demonstrate results obtained in the Galactic center.
16:50	0:30	Dr. Andrey Semena Dr. Andrey Semena IKI
ART-XC large scale deep surveys

17:20	0:30	Dr. Ilya Mereminskiy Dr. Ilya Mereminskiy IKI	The diverse population of X-ray sources in the ART-XC Galactic Plane Survey
The Mikhail Pavlinsky ART-XC Galactic Plane survey is designed to study different populations of Galactic sources - from faint cataclysmic variables to luminous X-ray binaries. However, the task of source classification - given the ART-XC angular resolution and crowdedness of the galactic stellar fields - is not a trivial one. We will discuss our ongoing efforts to employ different publicly available datasets in order to effectively select and study species of several populations - namely cataclysmic variables and X-ray sources with giant stars.
17:20	0:30	Dr. Ilya Mereminskiy Dr. Ilya Mereminskiy IKI
The diverse population of X-ray sources in the ART-XC Galactic Plane Survey

17:50	0:30	Andrey Mukhin Andrey Mukhin IKI	Maximum likelihood source detection applied to the 7 Ms Chandra Deep Field South
Likelihood function-based methods are a theoretically optimal way of detecting sources. They maximize the use of all available information about the telescope (background, PSF, etc.) and prior knowledge about the sources. Additionally, they do so without any binning applied to the data. Development of such a method and its application to the SRG/ART-XC data will be presented by A. Semena at this meeting. In this talk, we describe how this new method was set up and applied to the Chandra's Deep Field South. It is a unique X-ray dataset thanks to its record 7 Ms exposure and sub-arcsec spatial resolution of the telescope. Our preliminary results show that the gain in detection sensitivity is approximately equivalent to doubling the existing exposure.
17:50	0:30	Andrey Mukhin Andrey Mukhin IKI
Maximum likelihood source detection applied to the 7 Ms Chandra Deep Field South

18:20	3:00	Reception