Determination of the Mass of Igr J17091–3624 From “Spectro-Temporal” Variations During the Onset Phase of the 2011 Outburst

Iyer, Nirmal; Nandi, Anuj; Mandal, Samir

doi:10.1088/0004-637x/807/1/108

Cited by 72 publications

(76 citation statements)

References 52 publications

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“…In our current model we neglect the presence of the accretion disk corona. If we follow the mass estimation done by Iyer et al (2015), we get quite a consistent model for both microquasars' ν and ρ variability states -α ≈ 0.023 for the ν state and α ≈ 0.033 the ρ state, if only we assume the mass of IGR at the level of 9 − 10M , that is, close to the lower limit from results of Iyer et al (2015).…”

Section: Radiation Pressure Instability In Microquasarssupporting

confidence: 60%

“…Combining the results of Rebusco et al (2012) and later the GRS1915 mass estimation from Steeghs et al (2013) Table 6. Determination of α values based on the known IGR and GRS mass values (Rebusco et al 2012;Steeghs et al 2013;Iyer et al 2015) and mass-α relation presented in Table 5. Descriptions of the sources, their states and OBSIDs are presented in Table 5.…”

Section: Radiation Pressure Instability In Microquasarsmentioning

confidence: 99%

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Modified viscosity in accretion disks

Grzȩdzielski

Janiuk

2017

A&A

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Aims Black holes (BHs) surrounded by accretion disks are present in the Universe at different scales of masses, from microquasars up to the active galactic nuclei (AGNs). Since the work of Shakura and Sunyaev (1973) and their α-disk model, various prescriptions for the heat-production rate are used to describe the accretion process. The current picture remains ad hoc due the complexity of the magnetic field action. In addition, accretion disks at high Eddington rates can be radiation-pressure dominated and, according to some of the heating prescriptions, thermally unstable. The observational verification of their resulting variability patterns may shed light on both the role of radiation pressure and magnetic fields in the accretion process. Methods We compute the structure and time evolution of an accretion disk, using the code GLADIS (which models the global accretion disk instability). We supplement this model with a modified viscosity prescription, which can to some extent describe the magnetisation of the disk. We study the results for a large grid of models, to cover the whole parameter space, and we derive conclusions separately for different scales of black hole masses, which are characteristic for various types of cosmic sources. We show the dependencies between the flare or outburst duration, its amplitude, and period, on the accretion rate and viscosity scaling. Results We present the results for the three grids of models, designed for different black hole systems (X-ray binaries, intermediate mass black holes, and galaxy centres). We show that if the heating rate in the accretion disk grows more rapidly with the total pressure and temperature, the instability results in longer and sharper flares. In general, we confirm that the disks around the supermassive black holes are more radiation-pressure dominated and present relatively brighter bursts. Our method can also be used as an independent tool for the black hole mass determination, which we confront now for the intermediate black hole in the source HLX-1. We reproduce the light curve of the HLX-1 source. We also compare the duration times of the model flares with the ages and bolometric luminosities of AGNs. Conclusions With our modelling, we justify the modified µ-prescription for the stress tensor τ rφ in the accretion flow in microquasars. The discovery of the Ultraluminous X-ray source HLX-1, claimed to be an intermediate black hole, gives further support to this result. The exact value of the µ parameter, as fitted to the observed light curves, may be treated as a proxy for the magnetic field strength in the accretion flow in particular sources, or their states.

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Section: Radiation Pressure Instability In Microquasarssupporting

confidence: 60%

Section: Radiation Pressure Instability In Microquasarsmentioning

confidence: 99%

Modified viscosity in accretion disks

Grzȩdzielski

Janiuk

2017

A&A

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“…Kozlowski [50] sampled an accretion disc to be of temperature 20,000K, and the corresponding viscosity parameter is 0.044 for the BH mass 8.0X 10 8 M and 0.015 for 8.0 X 10 4 M . Next we will tabulate different values of α ss for known micro quasars: GRS 1915 + 165 and IGR 17091 − 324 [51][52][53]. We can clearly observe from the tables that the values of the different viscosity parameters we have used are completely supported by astrophysical data.…”

Section: Observational Evidence and Results From Different Simulationmentioning

confidence: 90%

Fate of an accretion disc around a black hole when both the viscosity and dark energy is in effect

Dutta

Biswas

2017

Eur. Phys. J. C

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This paper deals with the viscous accretion flow of a modified Chaplygin gas towards a black hole as the central gravitating object. A modified Chaplygin gas is a particular type of dark energy model which mimics of radiation era to phantom era depending on the different values of its parameters. We compare the dark energy accretion with the flow of adiabatic gas. An accretion disc flowing around a black hole is an example of a transonic flow. To construct the model, we consider three components of the Navier-Stokes equation, the equation of continuity and the modified Chaplygin gas equation of state. As a transonic flow passes through the sonic point, the velocity gradient being apparently singular there, it gives rise to two flow branches: one in-falling, the accretion and the other outgoing, the wind. We show that the wind curve is stronger and the wind speed reaches that of light at a finite distance from the black hole when dark energy is considered. Besides, if we increase the viscosity, the accretion disc is shortened in radius. These two processes acting together make the system deviate much from the adiabatic accretion case. It shows a weakening process for the accretion procedure by the work of the viscous system influencing both the angular momentum transport and the repulsive force of the modified Chaplygin gas.

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“…The mass accretion rate has been zoomed out in the inset in panel 1 of Figure 4 to show the accretion rate from only the inner sonic point after the shock gets expanded through the outer sonic point. -10Hz in many x-ray binaries and microquasars such as GRO J1655-40 , XTE J1118-480, XTE J1748-288, IGR J17091-3624 ( [18], [19], [20] , [21], [22]). We found that several models from our simulations show subtle and significant shock front oscillations over time.…”

Section: Resultsmentioning

confidence: 99%

Time Variability Of Low Angular Momentum Accretion Flows Around Black Hole.

Palit¹,

Janiuk²,

Suková³

2020

Proceedings of High Energy Phenomena in Relativistic Outflows VII — PoS(HEPRO VII)

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We present relativistic 2D and 3D GRMHD simulation of axisymmetric, inviscid, hydrodynamic accretion flows in a fixed Kerr black hole gravitational field. The flow is characterized by a low angular momentum with respect to a Keplerian one. A relativistic fluid where its bulk velocity is comparable to the speed of light, flowing in the accretion disk very close to the horizon should be described by the adiabatic index: 4/3 < γ < 5/3. The time-dependent evolution of shock position and respective effect on mass accretion rate and oscillation frequency with varying adiabatic index has been studied. Here we present some of the results for the adiabatic index = 1.4 in a 2D and 3D model. High Energy Phenomena in Relativistic Outflows VII -HEPRO VII

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Determination of the Mass of Igr J17091–3624 From “Spectro-Temporal” Variations During the Onset Phase of the 2011 Outburst

Cited by 72 publications

References 52 publications

Modified viscosity in accretion disks

Modified viscosity in accretion disks

Fate of an accretion disc around a black hole when both the viscosity and dark energy is in effect

Time Variability Of Low Angular Momentum Accretion Flows Around Black Hole.

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