BNO-SAO Conference 2017

Международная конференция
Сверхновая SN 1987A, кварковый фазовый переход в компактных объектах и многоволновая астрономия


2 - 8 июля 2017 г.

English / Русский

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vpetkov@inr.ru
sokolov@sao.ru

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Суббота, 1 июля. День заезда в Терскол (гостиница Вольфрам)

Будет организовано несколько рейсов транспорта из аэропорта Минеральные Воды в Терскол по мере прибытия участников Конференции.
15:00 - 18:00   Регистрация
18:00 - 20.00    Welcome party

Воскресенье, 2 июля. Терскол (гостиница Вольфрам)

9:00 - 9:15    Открытие конференции (V.B. Petkov, V.V. Vlasyuk, V.V. Sokolov)
     Секция: The 50th anniversary of Baksan Neutrino Observatory
9:15 - 9:45   V.V. Kuzminov (INR RAS). Baksan Neutrino Observatory: the 50-th anniversary. Current state and prospects.
Information about the history of creation of the Baksan Neutrino Observatory of INR RAS and its infrastructure is presented. Ground-based and underground facilities used to study cosmic rays, rare nuclear reactions and decays, register solar neutrino, observe various geophysical phenomena are described. Some main results obtained with these facilities and plans are given.
9:45 - 10:15    V.N. Gavrin (INR RAS) G.T. Zatcepin and contribution of Baksan Neutrino Observatory to neutrino astrophysics and physics of neutrino.
10:15 - 10:45   A.S. Lidvansky (INR RAS). A.E. Chudakov as a scientist and one of the founding fathers of underground physics.
Professor A.E. Chudakov has played an extremely important role in planning the lines of research for Baksan Neutrino Observatory and in designing several big facilities of it. But even before this, he had made invaluable contributions to very different fields of science, being a pioneer everywhere. Unfortunately, this outstanding scientist was rather careless about publications, and not many people are properly informed about his versatile activities. The aim of this short outline of his achievements is, using the opportunity of half-centenary jubilee of BNO, to fill up the obvious gap in people's common knowledge about this man and to partially correct the situation of injustice with respect to him.
10:45 - 11:15               Перерыв
      Секция: The 30th anniversary of SN 1987A
11:15 - 11:45    V.B. Petkov (INR RAS). SN 1987A: the first observation of neutrino emission from supernovae.
11:45 - 12:15   V.V. Sokolov (SAO RAS). The core collapse supernovae, gamma-ray bursts and SN 1987A.
If all long GRBs are related to supernovae (SNe) explosions indeed, then a long burst is the collapse of a massive star core or the beginning of an axially symmetric explosion of SN, and gamma-ray bursts (GRBs) must always be accompanied by an SN explosion (of Ib/c type or other types of core-collapse SNe). Then the total energy release of a burst source in gamma rays is in any case not higher that the total electromagnetic energy radiated by the SN (< or ∼ 1049 erg). The accumulated statistics of GRB + SN coincidences will confirm the GRB compact model more and more.
12:15 - 12:45   I.S. Savanov (INASAN, Moscow). History: SN1987A and the UV Astron mission.
The Astron orbital station was designed for astrophysical observations and was launched by Proton launch system on 23 March 1983. Astron had a 80cm ultraviolet telescope with a mass of 400kg and a complex of X-ray spectrometers with a mass of 300kg on board as a payload. Among the most important observations by Astron were those of SN 1987A. In future the World Space Observatory — Ultraviolet mission, planned for launch in 2021 will be able to become an essential tool of UV research in the following decade.
Presentation
12:45 - 14:30               Перерыв на обед.
      Секция: The 30th anniversary of SN 1987A
14:30 - 15:15   R.V. Novoseltseva (INR RAS). A search for neutrino bursts in the Galaxy at the BUST; exposure is 36 years.
We present the current status of the experiment on the search for neutrino bursts and results related to background events and the operating stability of the facility. As the target, we use two parts of the facility with the total mass of 240 tons. Over the period of June 30, 1980 to December 31, 2016, the actual observation time is 31.27 years. No candidate for the core collapse has been detected during the observation period. This leads to an upper bound of the mean frequency of gravitational collapses in the Galaxy fcol < 0.74 y-1 at 90% CL.
Presentation
15:15 - 15:45   L.A. Borodikhina (Kurchatov Institute, Moscow). Neutrino from stellar collapses.
The progress in supernovae collapses searches performed simultaneously by neutrino and gravitational wave detectors is reported. Current studies of Diffuse Supernova Neutrino Background as alternative approach to supernova research are discussed. Also several methods of neutrino flux registration from star collapses and Gamma Ray Bursts (GRBs) by modern low-background detectors are reviewed. Latest results of neutrino flux search from GRBs are being presented.
Presentation
15:45 - 16:15   M.M. Kochkarov (INR RAS). Fast neutron background in BUST for core-collapse supernova searches.
The natural neutron background influences the maximum achievable sensitivity in most deep underground physics experiments. Baksan Underground Scintillation Telescope (BUST) is a multipurpose neutrino detector. The detector BUST is able to detect core collapse neutrino burst via the inverse beta decay. The irreducible background is the neutron flux present at the experimental site, since neutrons produce the same signals as neutrinos do. In this paper we discuss our technique to measure low-intensity neutron fluxes and the application of this technique to the study of the neutron background from rock at the BUST experiment.
16:45 - 17 :15              Перерыв
      Секция: Multimessenger, neutrino, gamma and gravitational-wave astronomy
16:45 - 17:15   D.D. Dzhappuev, V.B. Petkov, A.S. Lidvansky, V.I. Volchenko, G.V. Volchenko, E.A. Gorbacheva, I.M. Dzaparova, N.F. Klimenko, A.U. Kudzhaev, A.N. Kurenya, O.I. Mikhailova, K.V. Ptitsyna, M.M. Khadzhiev, and A.F. Yanin (INR RAS). Search for diffuse cosmic gamma rays of energy Eγ > 100 TeV with the Carpet-3 air shower array
An experiment for measuring the flux of gamma rays of cosmic origin with energy above 100 TeV is currently being prepared at the Baksan Neutrino Observatory (the Carpet-3 experiment). The experiment performance will be accomplished after radical modernization of the existing array by substantially increasing areas of both the muon detector and ground level shower array. In this work some results of calculations of efficiency of the experiment for showers from primary gamma rays are presented for different configurations of the array. It is demonstrated that by increasing the muon detector area up to 615 m2 (the maximum possible value) one can reach with Carpet-3 the world-best sensitivity to 100 TeV gamma rays. The preliminary values of upper limits on the flux of cosmic diffuse gamma rays with energy higher than 900 TeV are also presented, derived from experimental data of the Carpet-2 shower array for a net exposure time of 9.2 years.
Presentation
17:15 - 17:45   M.M. Boliev (INR RAS). Search for astrophysical neutrino sources at the Baksan Underground Scintillation Telescope.
17:45 - 18:15   Alexander Johannes Stasik (DESY, Zeuthen, Germany). The IceCube Realtime Alert System.
IceCube is a 1 km3 Cherenkov neutrino detector located at the South Pole. The IceCube real time system provides the framework to reconstruct and analyse neutrino data with minimum delay to trigger follow up multi messenger observations. The talk focuses on the capabilities of the IceCube system as well as search strategies for transient sources. Recent results are also discussed.
18:15 - 18:45   A.N. Kurenya (INR RAS). Real-time multimessenger observation system for the search of optical counterparts of high energy events.

Понедельник, 3 июля

09:00 - 13:30          Экскурсия в БНО
15:00 - 19:00          Терскол (гостиница Вольфрам)
      Секция: Multimessenger, neutrino, gamma and gravitational-wave astronomy
15:30 - 16:00   A.F. Yanin. Development of a scintillation detectors based on the SiPM matrices: current status and prospects for the large volume neutrino detectors.
16:00 - 16:30   O.P. Zhelenkova, E.K.Majorova (SAO RAS). Multi range study of the radio sources of the RATAN-600 surveys.
    We present the results of the search of variable sources and transient events in the archive data of the sky surveys conducted on 3.9 GHz on the RATAN-600 radio telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) in 1980-1994. 17% of the total studied sources can be attributed to the long-term variables in radio range. About half of them has significant variations in optical brightness according to the data of the optical and infra-red catalogs.
    At a level of 3-5 r.m.s. we found three transient events. Using the data from radio and optical surveys and the VizieR, SIMBAD, and NED databases, we made assumptions on the possible nature of these events. The first transient is probably associated with AGN activity, the second one — with a cataclysmic GRB event or with a supernova, the origin of the third is not determined. The inference on the possibility of search for variable sources and transients using the data from the RATAN-600 blind surveys was drawn. According to our estimation the surface density of radio transients is 0.03 on one square angular degree with the detection level 8–11 mJy on 3.94 GHz.
    We compared the ratio of absolute magnitude to radio luminosity for sources with the active nucleus types determined from the optical data. It is found that this parameter is approximately the same for quasars with different radio luminosity. It is minimum for the strongest radio galaxies and grows up to the level characteristic of quasars with the decrease of radio luminosity. Considering that the ratio depends on obscuring properties of a dust torus, such behaviour can be explained if we assume that the torus geometry and its optical depth depend on the source long. This parameter is slightly higher among variable sources than among nonvariable ones which counts in favor of the nucleus more open to an observer.
16:30 - 17:00   B. E. Zhilyaev (MAO NASU), A.V. Sergeev (TF INASAN RAS, ICAMER) Detection of ultra-high-frequency variability with a deficit of quanta
    A technique for detecting harmonics in sparse quantum flows is developed when it is impossible to describe a light curve. A problem that is insoluble in the time representation can be exactly solvable in the Fourier frequency representation. To demonstrate the capabilities of ultra-high-frequency photometry, we present a numerical experiment. We show that at a sampling time of one microsecond on the 2 m telescope, harmonics can be detected in the frequency range up to 500 kHz for an object with U = 14.5. We demonstrate the application of the described technique to the analysis of gamma ray flare from the Compton Gamma Observatory CGRO. In the BATSE trigger No. 207 in an energy channel of 25-50 keV with flare duration of 0.030 ± 0.002 s, two significant harmonics at 190 and 310 kHz with half-widths of about 25 kHz are fixed, which correspond to velocities of 25,000 km / sec (~ 0.08 speed of light). The size of the object is estimated to be ~ 6000 km, and the size of the active region is ~ 484 km. A possible scenario for gamma-ray flare is the merging of a black hole of stellar mass and a neutron star.
17:00 - 17:30              Перерыв
17:30 - 18:00   V.V. Gorbachev (INR RAS). Probability of the frequency determination in the Fourier analysis.
18:00 - 18:30   S.V. Semenov (Kurchatov Institute, Moscow). Neutrino interaction with nuclei.
Calculations of neutrino interaction cross section with a number of neutron rich nuclei are performed. Neutrino inelastic scattering due to neutral current processes is considered. These reactions are essential for investigation of phenomena, taking place during the Supernova explosion and for construction of astrophysical neutrino detectors. Calculations of inelastic neutrino scattering cross section are produced by model independent method, which is based on experimental data on nuclear structure. The values of matrix elements of reaction under examination are determined from the characteristics of electromagnetic dipole М1-transitions in nuclei, obtained by the nuclear resonance fluorescence method.
Presentation

Вторник, 4 июля

09:00 - 14:30          Самостоятельные экскурсии.
16:00 - 19:00          Терскол (гостиница Вольфрам)
     Секция: Gravitational-wave astronomy
14:30 - 15:00   S.M. Popov, V.N. Rudenko (MSU). Current status of the GW-experiment and a discovery of gravitational waves.
15:00 - 15:30   L.E. Fesik (Saint-Petersburg State University). Localization of gravitational waves as a test of gravitation theory.
Detection of the gravitational wave events by Advanced LIGO antennas has opened the new possibility for the study high energy astrophysical processes and also fundamental physics of the gravitational interaction. A new method is presented for measuring the polarization state of an incoming GW by using localization of GW sources along the apparent circle of a detected event. The method takes into account the antenna-pattern functions for different polarization modes and the the detected strain ratio. In is shown that the apparent circles on the sky for allowed positions of the GW sources for the GW150914, GW151226 and LVT151012 events are parallel to the plane of the disc-like large scale structure known as the Local Super-Cluster (LSC) of galaxies which extends up to radius ∼100 Mpc and having thickness ∼30 Mpc.
     Секция: Low-background experiments
15:30 - 16:00   V.V. Sinev (INR RAS). Determination of 14C abundance in liquid scintillator.
Presence of 14C in liquid scintillator makes it impossible to install setup threshold below 200 keV. The 14C free detector can surely detect solar pp-cycle neutrinos as well as possible 40K antineutrino flux. Small liquid scintillator filled setup was installed at BNO INR RAS. First measurements demonstrated the possibility to measure small 14C abundances. The goal of the setup is to find a solvent with 14C abundance below 10 -20.
16:00 - 16:30   V.V. Kazalov (INR RAS). Search for 2K-capture of Kr-78 and Xe-124 at the Baksan Neutrino Observatory INR RAS.
16:30 - 17:00   B.K. Lubsandorzhiev (INR RAS). The GERDA experiment: search for Neutrinoless Double Beta Decay.
17:00 - 17:30              Перерыв
17:30 - 19:00              Discussion

Среда, 5 июля

Переезд в Нижний Архыз (САО).

Четверг, 6 июля. Нижний Архыз

     Секция: Multimessenger, neutrino, gamma and gravitational-wave astronomy.
9:00 - 9:30   V.V. Vlasyuk (SAO RAS). The strategy for the BTA granted time for alert observations of GRB afterglows, supernovae, and the identification of neutrino and gravitation signals.
Abstract.
Presentation
09:30 - 10:00   L.E. Fesik (Saint-Petersburg State University). GW170104 optical counterpart and possible scenarios of gravitational waves generation.
The gravitational wave event GW170104 detected by aLIGO is of an especial interest for a range of reasons. Firstly, it provides a test on different mechanisms of GW radiation. Besides the most common view on the GW source as a coalescing binary, in this work has been considered the scenario for a core-collapse supernova including a spherically-symmetric one and a massive supernova proposed by Imshennik and Nadezhin. The theoretical predictions have been applied to estimate physical parameters of such objects in order to provide the сriteria for the electromagnetic transients search.
Secondly, there has been used the proposed by authors method for source localization based on the construction of an apparent circle (AC) on the sky together with the beam pattern to the polarization state of an incoming GW. Interestingly, the AC for GW170104 is perpendicular to the Local Super-Cluster plane with some parts within it. Thus, the predicted positions of the source may belong to the LSC plane, which is consistent with detection of possible optical counterpart ATLAS17aeu.
10:00 - 10:30   Grzegorz Wiktorowicz (Astronomical Observatory of Warsaw University, Poland). Strange quark stars in binaries: formation rates, mergers and explosive phenomena. (Via Internet)
The existence of strange quark stars has been proposed many years ago. More recently, the possible co-existence of a first family composed of "normal" neutron stars with a second family of strange quark stars has been proposed as a solution of problems related to the maximum mass and to the minimal radius of these compact stellar objects. We studied the mass distribution of compact objects formed in binary systems and the relative fractions of quark and neutron stars in different subpopulations. According to our results, the main channel for strange quark star formation in binary systems is accretion on a neutron star. The number of double strange quark star systems is rather small with only a tiny fraction which merge within a Hubble time. This drastically limits the strangelets' pollution, and it rules out at least one relevant channel for the transformation of all neutron stars into strange quark stars.
Presentation
10:30 - 11:00   V.B. Petkov (INR RAS). Multimessenger search for evaporating primordial black holes
11:00 - 11:30              Перерыв
11:30 - 12:00   L.B. Bezrukov (INR RAS). Geoneutrinos and the Earth heat flux.
Non direct observations demonstrate that Earth heat flux could be sufficiently larger than one measured by using the temperature gradient method. Analysis of heat transfer channels also ensures that heat flux could be higher. At the moment data on 238U and 232Th antineutrino fluxes from KamLAND and Borexino measurements do not contradict the BSE model. Accurate measurement of all geoneutrino fluxes, including 40K antineutrino one, can clarify the situation.
12:00 - 12:30   A.M. Gangapshev (INR RAS). Search for the resonance absorption of solar axions emitted in the M1 transition of Kr-83 and Fe-57 nuclei in the Sun
A search for resonant absorption of the solar axions by Kr-83 nuclei was performed using the proportional counter installed inside the low-background setup at the Baksan Neutrino Observatory. The obtained model independent upper limits on axion-nucleon, - photon,- electron couplings are | g3AN — g0AN |≤8.4×10-7 , | g×mA |≤6.3×10-17, | gAe×mA |≤1.4×10-9 eV. The upper limit on axion mass is mA ≤ 65 eV at 95% C.L. New experiment using resonant absorption of the solar axions by Fe-57 nuclei is proposed. Different materials containing Fe-57 which can be used as detectors working media are described.
Presentation
12:30 - 13:00   Shashi Bhushan Pandey (ARIES, India). The 3.6m Devasthal optical telescope and optical transients. (Via Internet)
Longitudinal advantage of India is very much suitable for the time domain astronomy and particularly for time critical observations. Recently installed 3.6m Devasthal optical telescope along with back-end instruments are well suited for observations of energetic cosmic transients like Supernovae and Gamma-ray bursts. In this presentation, I summarize about the 3.6m DOT project along with proposed plans to study transients in near future.
Presentation
13:00 - 13:30   Alberto J. Castro-Tirado (IAA, Spain). Multiwavelength follow-up observations of GRBs. (Via Internet)
Abstract.
Presentation
После обеда        Экскурсия

Пятница, 7 июля. Нижний Архыз

     Секция: Multimessenger, neutrino, gamma and gravitational-wave astronomy.
9:30 - 10:10   Beskin G.M. (SAO RAS) et al. Search and study of optical transients in wide-angle monitoring of high temporal resolution.
Here we present the summary of first years of operation and the first results of a novel 9-channel wide-field optical monitoring system with sub-second temporal resolution, Mini-MegaTORTORA (MMT-9), which is in operation now at Special Astrophysical Observatory on Russian Caucasus. The system is able to observe the sky simultaneously in either wide (~ 900 sq.deg.) or narrow (~ 100 sq.deg.) fields of view, either in white light or with any combination of color (Johnson-Cousins B, V or R) and polarimetric filters installed, with exposure times ranging from 0.1 s to hundreds of seconds.The real-time system data analysis pipeline performs automatic detection of rapid transient events, both near-Earth and extragalactic. The objects routinely detected by MMT include faint meteors and artificial satellites.
Presentation
10:10 - 10:50   D. I. Makarov (SAO RAS). Mean density of matter in the Local Universe.
The Local Supercluster is an ideal laboratory to study distribution of luminous and dark matter in the nearby Universe. In total, 54% of galaxies in the Local Universe are gathered into groups. The groups collect 82% of the K-band light. The local matter density is Ωm= 0.08 within a distance of ~40 Mpc assuming H0=73 km s-1 Mpc-1. It is significantly smaller than the cosmic value, 0.32, in the standard ΛCDM model. The discrepancy between the global and local quantities of Ωm may be caused by the existence of a dark matter component unrelated to the virial masses of the galaxy systems.
Presentation
10:50 - 11:30   Guido Pizzella (Universita di Roma, Italy) Galileo versus Aristotle: the case of Supernova 1987A (Via Internet)
Most current supernova theories state that this phenomenon lasts a few seconds and ends with a big final explosion. However, these theories do not take into account several experimental results obtained with neutrino and gravitational wave detectors during the explosion of SN1987A, the only supernova observed in a nearby galaxy in modern age. According to these experimental results the phenomenon is much more complex that envisaged by current theories, and has a duration of several hours. Furthermore, correlations between the neutrino and two gravitational wave detectors, ignored by most of the scientific community, were observed during the longer collapse time. We draw the attention to three of these observations, which have not taken into proper consideration even if they are among the most important ones: a) the long duration of the Kamiokande neutrino burst; b) the coincidences between the LSD and BAKSAN detectors; c) the correlation between neutrino and gravitational wave detectors. Since the current "standard" theories, based on some rough simplifications, are a clear example of an Aristotelian attitude, still present in our days, we believe that a more Galilean attitude is necessary, being the only correct way for the progress of science.
Presentation
11:30 - 12:00              Перерыв
12:00 - 12:30   Yu.V. Baryshev (SPbSU), S.A. Oschepkov (CFU) Gravitation theory in multimessenger astronomy I: comparison of geometrical and field approaches to the physics of gravitational interaction. (Via Internet from St-Petersburg SAO Department)
The goal of modern multimessenger astronomy is to understand high energy astrophysical phenomena related to compact relativistic objects (neutron and quark stars), candidates for black holes of stellar and galactic masses, gravitational waves (GW) and its detection, massive supernova explosions, gamma ray bursts, central energy machine and jets from active galactic nuclei. The common basis for all this observed phenomena is the theory of gravitation, for which in modern theoretical physics there are two main directions: Einstein's geometrical and Feynman's nonmetric field approaches for description of gravitational interaction (arXiv:1702.02020). Basic principles and equations of these two theories are discussed.
Presentation
12:30 - 13:00   Yu.V. Baryshev (SPbSU), S.A. Oschepkov (CFU) Gravitation theory in multimessenger astronomy II: crucial observational tests based on GW and optical observations. (Via Internet from St-Petersburg SAO Department)
Main theoretical predictions of the geometrical and field approaches which important for the multimessenger astronomy are given. Crucial observations, which allow testing the physics of the gravitational interaction, are discussed, including detection of gravitational waves and follow-up observations for its localization. The main difference between geometrical and field gravitation theories is that the field theory predicts the localizability of the energy of the gravitational field, while in geometrical theory due to pseudo-tensor character of gravity energy there is no adequate physical description of the GW localization and the structure of the relativistic compact objects.
13:00 - 13:30   S.I. Shirokov (SPbSU), A.A. Raikov (GAO RAS) Spatial distribution of GRBs with known redshifts. (Via Internet from St-Petersburg SAO Department)
The conditional density method and the pairwise distances method for studying the gamma-ray bursts spatial distribution are used. The GRB sample is based on SWIFT program and includes 364 objects with measured redshifts and fluences. The main sample is divided into two cases. In both cases the entire celestial sphere up to 8 Gpc is taken, but in the second case without the Galactic belt. As a reference sample we use comparison of a real sample with uniform distributions within the same geometry and the same number of points. Also we perform the modeling of the luminosity function and Malmquist bias that allows to consider the total sample without additional cuts such as volume limited subsamples. Our statistical analysis shows that the fractal dimension of the GRB sample is D = 2:6 ± 0:1 on 2 - 6 Gpc.
Presentation
После обеда        Экскурсия

Суббота, 8 июля.

     Секция: Compact astrophysical objects and QCD phase transition.
9:00 - 9:40   A. Yudin (ITEP, Moscow). On possible consequences of multiple phase transitions inside hybrid stars.
We explore the consequences of a possible multiple phase transitions inside hybrid stars – stars which contain a core made of quark matter. The ordinary approach to consider the way, quark phase appears at growing density (pressure) is the phase transition between hadron matter (made of neutrons, protons, hyperons etc) and uniform quark "sea". But there exists another possibility: this transition could also proceeds though some intermediate (stable at high density) multiquark state, or a sequence of such states. In the framework of a simple bag-model like EoS parameterization we consider the effects connected with this possibility. One of the main questions here is the influence on maximum mass of hybrid star. We explore this problem both numerically and theoretically with variational principle arguments.
Presentation
09:40 - 10:20   Yu.A. Shibanov (Ioffe Institute, StPetersburg), G.M. Beskin, S.V. Karpov, V.l. Plokhotnichenko, V.V. Sokolov (SAO RAS), D. Zyuzin (Ioffe Institute, StPetersburg), A. Kholtygin, Yu. V. Baryshev (SPbSU) Direct observations of transformation of low-massive binaries to millisecond radio pulsars and back.
Here we report the results of high temporal resolution photopolarimetric observations on the Russian 6-m telescope of a close binary system containing a millisecond pulsar MSP J1023+0038 in accreting state. In the B photometric band we detected the stochastic variability on time scales from 0.5 seconds to minutes with 20-50% amplitude, with minimal rise times down to 0.2 seconds. The linear polarization remained constant and equal to 1.5% during these variations on 10 minutes time scale. We also detected a r~0.7 correlation between the emission in U and B bands. Moreover, at some moments we detected a quasi-periodical flux variations on 2.3-2.8 seconds time scale. We discuss the possible physical nature of these effects.
Presentation
10:20 - 11:00   V.V. Sokolov (SAO RAS). Gravidynamics (scalar-tensor gravitation) and the observed discrete mass spectrum of compact stellar remnants in close binary systems.
There is a considerable gap between masses of neutron stars (NS) and black hole (BH) candidates in close binary systems (CBSs: the observed mass spectrum of NSs and BH candidates shows an obvious absence of compact objects with masses within the interval from 2 M to ≈ 6 M. The main purposes in this short overview are to draw attention:
(1) to the discussion about the discrete mass spectrum problem of the compact objects in the stellar CBSs,
(2) to 6.7 M peak in the observed collapsar mass distributions, and
(3) to probable interpretations the observed mass spectrum, which is rather similar to line one.
11:00 - 11:40   S.A. Trushkin, S.N. Fabrika, P.G. Tsybulev (SAO RAS). Future Fast Radio Bursts (FRB) search with the RATAN-600 radio telescope at 4.7 GHz.
     We decided to begin the search program of the mysterious and rare fast radio bursts (FRB) with the RATAN-600 radio telescope. We are preparing the special antenna - the Western Sector and the secondary mirror (SM) named by Type-5. Thus the expected effective area of the antenna will be near 1500 meter in square. The special four high sensitivity receivers at 4.7 GHz will be established in the focal plane of SM. The total frequency band of 600 MHz of each receiver will be divided by the microwave filters on four sub-bands of 150 MHz and all signals of 16 channels of back-end will be record with the maximal temporal resolution 0.5 ms. The special online routine on the powerful PC will analyze the coming signals in order to find the fast bursts, shifted in time due to the interstellar (or intergalactic) dispersion (DM ~ 100-1000 pc/cm3) in dependence on the sub-band frequencies. Alerts of the such distant (out of the Solar system) events with expected fluxes 1-30 Jy and error box of coordinates will be send to the robotic optical wide-angular small telescopes array constructing in SAO RAS. The relatively big field of view of the four-beam system in the 24-hours survey allows us to detect 10-50 FRB per year. In June 2017 we have carried out the pilot observations of the bright and close pulsar PSR B0329+54 at 2.3 and 4.7 GHz with wide-band (120 and 600 MHz respectively). We have detected the 10-30 pulses with the known spin period P=0.71452s getting in the antenna beams, recorded with time interval 0.5ms. The width of the average pulse is equal to W50=10 ms at 4.7 GHz. Such measurements are well test for future FRB search. We propose to start of the survey in July 2017.
Presentation
11:40 - 12:10              Перерыв
12:10 - 12:40   S.N. Fabrika (SAO RAS). Ultraluminous X-ray sources: new data.
    The origin of Ultraluminous X-ray Sources (ULXs) in external galaxies whose X-ray luminosities exceed those of the brightest black holes in our Galaxy by hundreds and thousands of times is mysterious. The most popular models for the ULXs involve either intermediate mass black holes (IMBHs) or stellar-mass black holes accreting at super-Eddington rates. Here we review the ULX properties. Their X-ray spectra indicate a presence of hot winds in their accretion disks supposing the supercritical accretion. In recent years, new surprising results were discovered in X-ray data, ULX-pulsars and high-velocity outflows up to 0.2c. They are also in accordance with the super-Eddington accretion. However, the strongest evidences come from optical spectroscopy. The spectra of the ULX counterparts are very similar to that of SS433, the only known supercritical accretor in our Galaxy. The spectra are apparently of WNL type (late nitrogen Wolf-Rayet stars) or LBV (luminous blue variables) in their hot state, which are very scarce stellar objects. We find that the spectra do not originate from WNL/LBV type donors but from very hot winds from the accretion disks, which have similar physical conditions as the stellar winds from these stars. The results suggest that bona-fide ULXs must constitute a homogeneous class of objects, which most likely have supercritical accretion disks.
Presentation
12:40 - 13:10   T.A. Fatkhullin (SAO RAS). The monitoring of supernovae with the 6-meter telescope of SAO RAS.
We report about a long-term core-collapse supernovae focused observational program carried out with the SAO RAS 6-meter telescope. Historically the main underlying reason of starting such a program was the fact of close relation between cosmic gamma-ray bursts (GRB) and core-collapse supernovae (CCSNe). We show some of results of our spectroscopic and photometric SNe monitoring with and without GRB, our attempts of data interpretation. Finally, we summarize scientific goals, discuss problems and the program prospectives.
Presentation
13:10 -    Общая дискуссия
18:00   Банкет

Воскресенье, 9 июля .

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