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Документ 3D numerical hydrodynamical models of the precessing thick accretion disk and ON- and OFF-state generations in microquasars(Одеський національний університет імені І. І. Мечникова, 2017) Nazarenko, V. V.; Nazarenko, S. V.The thick accretion disk and donor’s wind on the example of CYG X-1 are computed. The main aim of the present simulations is to calculate the precessing thick accretion disk and ON- and OFF-state generation by the methods of 3D numerical hydrodynamics. The main task of the present research is to investigate the dependencies of the central disk temperature and mass accretion rate versus time. Non-stationary Euler’s hydrodynamical equations are resolved by astrophysical variant of large-particle method by Belotserkovskii & Davydov. The ON- and OFF-state generation for the precessing thick accretion disk was setting. The correlation between radio flux and X-ray was setting. Our present calculations also show that in the cases of the thick accretion disk the jet velocities will be close to 0.24-0.26 of light speed (see for instance SS433) and on contrary in the cases of a thin accretion disk jet velocities will be close to 0.98-0.99 of light speed (see for instance CYG X-1).Документ 3D numerical hydrodynamical simulations of a radiation-driven jet launch and disappearing over low/hard state(Одеський національний університет імені І. І. Мечникова, 2016) Nazarenko, V. V.; Nazarenko, S. V.In the present research we have calculated 3D numerical hydrodynamical simulations of a radiation-driven jet launch and disappearing over low/hard state. The calculations show that the jet launch occurs at the beginning of the low/hard state over 10-30 minutes of the orbital time. The jet disappearing occurs over the short time scale (of the order of 10-30 minutes of the orbital time) at the end of the low/hard state. The calculations also show that the temperature near the accretor is increased in 100-200 times over low/hard state relatively high/soft. The mass accretion rate in the disc is anti-correlated with the temperature near the accretor in our calculations.Документ 3D numerical hydrodynamical simulations of a radiation-driven jet launch and disappearing over low/hard state(Одеський національний університет імені І. І. Мечникова, 2016) Nazarenko, V. V.; Nazarenko, S. V.In the present research we have calculated 3D numerical hydrodynamical simulations of a radiation-driven jet launch and disappearing over low/hard state. The calculations show that the jet launch occurs at the beginning of the low/hard state over 10-30 minutes of the orbital time. The jet disappearing occurs over the short time scale (of the order of 10-30 minutes of the orbital time) at the end of the low/hard state. The calculations also show that the temperature near the accretor is increased in 100-200 times over low/hard state relatively high/soft. The mass accretion rate in the disc is anti-correlated with the temperature near the accretor in our calculations.Документ The 3-D numerical simulations of the dependence of the disk structure from the wind configuration in one-point in microquasar CYG X-1. The case of the high resolution grid in the vertical direction(Одеський національний університет імені І. І. Мечникова, 2021) Nazarenko, V. V.The present paper is devoted to the investigation how the disk structure is depending from the one-point wind one in microquasar CYG X-1. The results show that when the region in which the wind is absent in the vicinity of one-point has the size less or equal to 0.07 the disk radius is very small, order of 0.08 in units of orbital separation. When this size is increased to 0.115 the disk radius becomes to be of standard size to be equal to 0.22 in units of orbital separation. By the other words these results show that the disk structure is strong depending from many factors including and the donor’s wind configuration in the vicinity of one-point. This configuration is inherent to microquasars only. Indeed, since microqausars are the massive close binary systems; the donor in these systems is massive star from which the strong radiationdriving wind is blowing. On the other hand, in microquasars accretion disks are present and it means that one-point stream is also present in microqausars. It in turn means that the matter configuration in the vicinity of one-point is very complicated since the high mass loss rate donor’s wind and one-point stream must be existing in the vicinity of one-point simultaneously. This situation maybe resolved when we suppose that the central source in an accretion disk will influence on the donor’s atmosphere structure in the vicinity of one-point and in turn will be result in the break of wind in the vicinity of one-point. This finally will be means that one-point stream will be existing in onepoint without a wind and it, flowing in the accretor’s Roche lobe, will be result in an accretion disk formation. Here one problem is arising: what is the config uration of wind in the extended vicinity of one-point and from what the parameters this configuration is depending and haw this configuration will be results to the disk structure change. We good understand that this situation is arising in the case of microquasars only and we try to resolve this problem in the present paper.Документ The 3-D numerical simulations of the small radius accretion disk formation in microquasar CYG X-1. The case of the high resolution grid in the vertical direction(Одеський національний університет імені І. І. Мечникова, 2021) Nazarenko, V. V.The present paper is devoted to small radius accretion disk formation in microquasar CYG X-1. The results show that in the case of the strong wind action on a disk the disk radius is about of 20 ÷ 30 per sent of accretor’s Roche lobe radius (it is about of 0.08 of orbital separation) instead of the standard disk radius equal to 80 ÷ 85 per sent of accretor’s Roche lobe radius (the last magnitude is a disk radius equal to 0.22 of orbital separation). In the present paper we try to resolve the problem that is arising in the case of microquasars when we investigate the accretion disk formation in these objects. Indeed, since the micro quasars are the massive close binary systems (MCBS) in which the donor is massive stars of O-B class the strong wind is blowing from these stars. In this case the problem is arising: what is the situation in which an accretion disk in microqausars is formed. By the other words, it means what are the processes and the matter that are responsible for an accretion disk for mation in microquasars: is this matter from one-point stream only or a disk is formed from the donor’s wind in essential or one is formed from both processes simul taneously. This question is not idle since one is strong affects on ON-OFF state generations in the precession mechanism model. Since this mechanism is strong de pending from the magnitude of the disk centre density and all the parameters affecting on it are very impor tant for calculations. The matter configuration in the vicinity of one-point is one of these parameters that strong affects on ON-OFF state production and disk structure and the central disk density. By this reason we have investigated in the present paper how the disk structure is depending from the wind configuration in the vicinity of one-point.Документ The dependence of on- and off-state generations in classical microquasars from the disk density. 3-D numerical hydrodynamical simulations of the high and low mass accretion rate in accretion disk in microquasar CYG X-1(Одеський національний університет імені І. І. Мечникова, 2018) Nazarenko, V. V.; Назаренко, В. В.In the present work we have computed and have compared the on- and off- generations in low and high mass accretion rate accretion disks. The comparison shows that in the case of low mass accretion rate in disk (10~10 solar mass per year) the ON-state time interval is very short, order of 0.2 ^ 0.4 of precession period; in the case of high mass accretion rate in disk (10~9 solar mass per year) the ON-state time interval is relatively long, order of 0.7 ^ 0.9 of precession period. This shows that in the case more dense disk ON-states are relatively very long time interval because of high mass accretion rate in disk. This result is natural for classical microquasar (CYG X-l) in which the on-states are corresponding high mass accretion rates. For comparison we may also write that the time intervals of OFF-states in the present calculations are order of 1.3 ^ 1.5 of precession periods. The calculations also show that in OFF-states the accretion disk have the low specific viscosity and on contrary have the high specific angular momentum. In ON-states the disk have to contrary to OFF-states the high specific viscosity and low specific angular momentum. It shows that in OFF-states the disk is very rapidly rotating with low viscosity. In ON-states the situation is on contrary. Such the disk time-behaviour is true for both low and high mass accretion rate. The calculations also show that in ON-states the disk radius is very small, order of 0.08 of the orbital separations and on contrary in OFF-states the disk radius is relatively large, order of 0.25 of the orbital separations. The stated above shows that the disk is strong transformed from ON- to OFF- states.Документ THE NUMERICAL THREE-DIMENSIONAL HYDRODYNAMIC SIMULATION OF COLLIDING STELLAR WINDS IN A CLOSE BINARY SYSTEM(Astroprint, 2013) Nazarenko, V. V.; Glazunova, L. V.; Nazarenko, S. V.In the present numerical study the stellar winds from both supergiant-components of a detached close binary system (CBS) are simulated applying methods of the three-dimensional numerical hydrodynamics. The simulated winds collide in the space between the components, forming a stationary shock wave. That shock wave has geometrically intricate shape that consists of several separate filamentary structures. The temperature in the shock wave is about 105K, and the temperature in the space adjacent to the shock wave is around 104 - 1.5 104K. Away from the line-of-centres the shock wave is curved due to the effect of the Coriolis forces and greatly expands under the gas pressure at that. At a distance of about two orbital separations from the line-of-centres the shock wave expands so much that it is practically smearing out in space.Документ THE NUMERICAL THREE-DIMENSIONAL HYDRODYNAMIC SIMULATION OF THE -RAY BURSTERS AND X-RAY BURSTERS(Astroprint, 2013) Nazarenko, V. V.; Glazunova, L. V.; Nazarenko, S. V.An radiative wind accretion onto the compact object in a detached close binary system (CBS) where one of the components is a supergiant with radiation stellar wind that blows from its surface, and another component is a compact object (black hole or neutron star), is simulated applying methods of three-dimensional numerical hydrodynamics. The simulation of bursts similar to the gamma-ray bursters and X-ray bursters, i.e. isolated bursts with nearly zero in time ascending and descending branches with amplitudes from 6 - 7m to 15 - 18m, commences in the vicinity of the compact object when the precession of the donor star starts. Due to the course numerical spatial grid of 0.01 units of the orbital separation, the duration of such isolated bursts is 10-40 minutes of the orbital time. The burst simulation is as follows: when the donor stars precession starts, small grid-cell-sized regions of higher density appear in the vicinity of the compact object due to the RayleighTaylor instability. The temperature in one of those regions increases abruptly when they interact with the stellar wind from the donor star. Prior to the temperature increase, the indicated regions were radiopaque. When the temperature reaches its peak, those regions become radiolucent, and all energy contained there is momentarily illuminated, giving off a burst that appears as an isolated sharp peak. That is how the bursts similar to the gamma-ray bursts and X-ray bursts are simulated.Документ The ON- And OFF-state generations in the case of the thick accretion disk and undefined precession period. 3-D numerical hydrodynamical simulations in accretion disk in microquasar CYG X-1(Одеський національний університет імені І. І. Мечникова, 2019) Nazarenko, V. V.; Назаренко, В. В.. In the present work we have computed the thick accretion disk (the accretion disk with radiation pressure) for the case of undefined precession over very long time (more than 14 precession periods). The calculations show that in this case the origin of the ON-states and OFF-states are strong irregular in time. The calculations also show that the jet’s launches are taking place very suddenly over 7 ÷ 20 minutes of the orbital time. The jet’s launches over OFF-states occurs discrete as it is observed in real microquasars.Документ The ON-and OFF-state generations in classical microquasars. 3-D numerical hydrodynamical simulations on high resolution grid in the case of intermediate mass transfer rate in accretion disk of microquasar CYG X-1(Одеський національний університет імені І. І. Мечникова, 2020) Nazarenko, V. V.; Назаренко, В. В.In the present work we have computed the accretion disk time evolution over 50 orbital periods on high resolution grid (the grid size is equal to 140*180*140) for microquasar CYG X-1 for the case of intermediate mass transfer rate (the initial one-point density is equal to 8.184 1012 cm3, that corresponds to mass transfer rate order of 5 109 solar mass per year). Our task in the present research is to generate ON-OFF-states (high/soft+low/hard states) in the accretion disk of the given microquasar. For this purpose we will simulate the precession motion of an accretion disk (the precession period is equal to 8 orbital ones in the present simulations). Thus, our key goal in the present work is to show that the precession motion in an accretion disk of microquasars results in ON-OFF state production. We have used the radiation cooling explicitly to obtain the real magnitudes of temperature in the calculations. The results show that in disk over the precession motion the mass accretion rate modulation occurs. This modulation is such that the states of low accretion rate replaced by the high accretion rate states, thus this replacement occur on the very short time scales, order of 15 20 minutes that in turn makes about of 0.0025 of orbital period. The relation of the magnitude of accretion rate between both states is by a factor of 100. The centre disk temperature also shows the strong modulations in the magnitudes. These temperature modulations are that that centre disk high temperatures are corresponding to the low mass accretion rate and centre disk low temperatures are corresponding to the high mass accretion rate. We interpret this situation as ON-OFF-state (high/soft - low/hard states) generation in our calculations. The ON-state time intervals are equal to OFF-state time intervals and these intervals are equal to 2 precession periods. The calculations also show that the time intervals of OFF-state are longer in space below orbital plane relatively these intervals upper orbital plane. This circumstance is explained by as follows: the one-point stream motion is strong nonuniform over the precession motion. The most part of this stream is moving upper orbital plane and a gas is more dense in this space. Thus, a gas in space in the disk centre below orbital plane have the relatively small density and radiation cooling is not effective in this case. The temperatures are strong increased in this case and the jets are launched more often in the disk centre below orbital plane in our present research. Finally we may conclude that we show above haw the precession mechanism of ON-OFF-state (high/soft - low/hard states) generation is working in our present research.Документ THREE-DIMENSIONAL NUMERICAL HYDRODYNAMIC SIMULATION OF ON- AND OFF-STATES IN MICROQUASARS AND QUASARS(Astroprint, 2014) Nazarenko, V. V.; Nazarenko, S. V.As is shown in the present computations performed using three-dimensional numerical astrophysical methods, in microquasars in the course of precession of the accretion disc blown by the donor’s wind the on- and off-states start being generated in the disc. In our case, the transition between these states takes 30-40 minutes of the orbital time. In the off-state the temperature changes discretely, i.e. such a change appears as separate sharp peaks, which almost merge with each other over time.Документ Three-dimensional numerical hydrodynamical simulation of low/hard and high/soft states in accretion discs of microquasars and quasars on base of undefined precession(Одеський національний університет імені І. І. Мечникова, 2015) Nazarenko, V. V.; Nazarenko, S. V.In this study, the models of slaved precession of accretion disc and donors radiationdriven wind were performed using three-dimensional numerical astrophysical methods by the example of microquasar Cyg X-1. As is shown, in the course of precession of the accretion disc blown by the donor’s wind the states with high and low temperature (low and high mass accretion rate, respectively) start being generated in the centre of disc. Our computations of disc precession performed on base of undefined precession that means each point of rotation axis of accretion disc makes unclosed difficult curve instead of a circle as it is in case of definite precession. In this case, the transition between states of high and low temperature takes place irregularly and not depend on precession period. The duration of transition between these both states is less than intervals of states on several orders of magnitudes.