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We examine radiative standing shocks in advective accretion flows around stellar-mass black holes by 2D radiation hydrodynamic simulations, focusing on the super-Eddington accreting flow. Under a set of input flow parameters responsible for…

High Energy Astrophysical Phenomena · Physics 2021-02-24 Toru Okuda , Chandra B. Singh

We consider the fuelling of the central massive black hole in Active Galactic Nuclei, through an inhomogeneous accretion flow. Performing simple analytical treatments, we show that shocks between elements (clumps) forming the accretion flow…

Astrophysics · Physics 2009-11-13 W. Ishibashi , T. J. -L. Courvoisier

We present global solutions of optically thin, two-temperature black hole accretion disks incorporating magnetic fields. We assume that the {\pi}{\phi}-component of the Maxwell stress is proportional to the total pressure, and prescribe the…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Hiroshi Oda , Mami Machida , Kenji E. Nakamura , Ryoji Matsumoto , Ramesh Narayan

Adopting the advection dominated accretion flow (ADAF) model, we have re-examined the radiation emitted by isolated stellar-mass black holes accreting from the interstellar medium of our Galaxy. Two distinct types of black holes are given…

Astrophysics · Physics 2009-10-30 Y. Fujita , S. Inoue , T. Nakamura , T. Manmoto , K. E. Nakamura

We calculate the structure and neutron content of neutrino-heated MHD winds driven from the surface of newly-formed magnetars (``proto-magnetars'') and from the midplane of hyper-accreting disks, two of the possible central engines for…

Astrophysics · Physics 2009-11-13 Brian D. Metzger , Todd A. Thompson , Eliot Quataert

Nova-likes such as BZ Cam are high state Cataclysmic Variables showing hard X-ray emission that can be characterized with advective hot flows in the inner accretion disk. We explore Chandra High Energy Transmission Grating (HETG)…

High Energy Astrophysical Phenomena · Physics 2026-04-14 Solen Balman , Eric M. Schlegel , Patrick Godon , Jeremy J. Drake , Edward M. Sion

Black holes that accrete far below the Eddington limit are believed to accrete through a geometrically thick, optically thin, rotationally supported plasma that we will refer to as a radiatively inefficient accretion flow (RIAF). RIAFs are…

High Energy Astrophysical Phenomena · Physics 2015-09-23 Mani Chandra , Charles F. Gammie , Francois Foucart , Eliot Quataert

We report the highest compression reached in laboratory plasmas using eight laser beams, E$_{laser}$$\approx$12 kJ, $\tau_{laser}$=2 ns in third harmonic on a CD$_2$ target at the ShenGuang-II Upgrade (SGII-Up) facility in Shanghai, China.…

We show that the inner regions of a cool accretion disk in an X-ray binary can transform into an advective, ion supported accretion flow (an optically thin ADAF, here called ISAF), through events involving only the known properties of the…

Astrophysics · Physics 2009-11-07 H. C. Spruit , B. Deufel

There is a maximum for the gravity of a black hole in the vertical direction in the accretion disc. Outflows may probably be driven from the disc if the radiation flux of the disc is greater than a critical value corresponding to the…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Xinwu Cao , Wei-Min Gu

Radiatively inefficient accretion flows (RIAFs) are believed to power supermassive black holes (SMBH) in the underluminous cores of galaxies. Such black holes are typically accompanied by flat-spectrum radio cores indicating the presence of…

High Energy Astrophysical Phenomena · Physics 2014-10-08 Monika Moscibrodzka , Heino Falcke , Hotaka Shiokawa , Charles F. Gammie

The growing evidence for supermassive black holes in the centres of nearby galaxies has brought into sharper focus the question of why elliptical galaxies, rich in hot gas, do not possess quasar-like luminosities. Recent studies suggest…

Astrophysics · Physics 2015-06-24 T. Di Matteo , A. C. Fabian , M. J. Rees , C. L. Carilli , R. J. Ivison

We examine unresolved nuclear X-ray sources in 57 brightest cluster galaxies to study the relationship between nuclear X-ray emission and accretion onto supermassive black holes (SMBHs). The majority of the clusters in our sample have…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 H. R. Russell , B. R. McNamara , A. C. Edge , M. T. Hogan , R. A. Main , A. N. Vantyghem

X-ray assisted nuclear excitation by electron capture (NEEC) into inner-shell atomic holes in a plasma environment generated by strong optical lasers is investigated theoretically. The considered scenario involves the interaction of a…

Plasma Physics · Physics 2019-12-18 Yuanbin Wu , Christoph H. Keitel , Adriana Pálffy

Rather than accreting via a disk, some White Dwarfs (WDs) in quiescent Dwarf Novae (DN) could accrete via an Advection-Dominated Accretion Flow (ADAF) possibly responsible for the X-ray Bremsstrahlung emission observed. Such a hot accretion…

Astrophysics · Physics 2009-10-31 Kristen Menou , Rosalba Perna , John Raymond

Neutron stars in close binary star systems often accrete matter from their companion stars. Thermonuclear ignition of the accreted material in the atmosphere of the neutron star leads to a thermonuclear explosion which is observed as an…

Particle heating in advection-dominated accretion flows (ADAFs) by nonlinear MHD (Alfvenic) turbulence is investigated. Such turbulence with highly-fluctuating magnetic fields, $\tilde B\sim B_0$, is believed to be naturally produced by the…

Astrophysics · Physics 2015-06-24 Mikhail V. Medvedev

Plasmas in an accretion flow are heated by MHD turbulence generated through the magneto-rotational instability. The viscous stress driving the accretion is intimately connected to the microscopic processes of turbulence dissipation. We show…

Astrophysics · Physics 2007-07-04 Siming Liu , Christopher L. Fryer , Hui Li

Collimated relativistic outflows, or jets, are amongst the most energetic and relativistic phenomena in the Universe. They are associated with supermassive black holes in distant active galactic nuclei (AGN), accreting black holes and…

The hard to soft state transition of the outbursts in X-ray binaries (XRBs) is triggered by the rising of the mass accretion rate due to the disk instability. In order to explain the observed correlation between the hard X-ray transition…

High Energy Astrophysical Phenomena · Physics 2021-10-20 Xinwu Cao , Bei You , Zhen Yan