Related papers: Accretion and Outflow in V404 Cyg
Using BATSE and RXTE observations from 1991 April to 2001 August we have detected 71 outbursts from 82 periastron passages of EXO 2030+375, a 42-second transient X-ray pulsar with a Be star companion, including several outbursts from 1993…
Protostellar outflows often present a knotty appearance, providing evidence of sporadic accretion in stellar mass growth. To understand the direct relation between mass accretion and ejection, we analyze the contemporaneous accretion…
The accretion-powered millisecond pulsar IGR J00291+5934 underwent two ~10 d long outbursts during 2008, separated by 30 d in quiescence. Such a short quiescent period between outbursts has never been seen before from a neutron star X-ray…
Low mass X-ray binaries (LMXBs) show evidence of a global correlation of debated origin between X-ray and optical luminosity. We study for the first time this correlation in two transient LMXBs, the black hole V404 Cyg and the neutron star…
We report on a 120 ks Chandra/HETG spectrum of the black hole GRS 1915+105. The observation was made during an extended and bright soft state in June, 2015. An extremely rich disk wind absorption spectrum is detected, similar to that…
More than half of all low-redshift AGN exhibit UV and X-ray absorption by highly ionized gas. The observed UV and X-ray absorption lines are almost always blue-shifted at velocities of hundreds of km/s, indicating that the absorbing gas is…
I present results from numerical simulations of gas dynamics outside luminous accretion disks in active galactic nuclei. The gas, gravitationally captured by a super massive black hole, can be driven away by the energy and momentum of the…
We report results from a Giant Metrewave Radio Telescope (GMRT) monitoring campaign on the black hole X-ray binary V404 Cygni during its 2015 June outburst. The GMRT observations were carried out at observing frequencies of 1280, 610, 325…
We examine the light curve of the July-August 2001 superoutburst of WZ Sagittae. During the decline from maximum light the locally defined decay time increases from ~4 d/mag to ~12 d/mag over the first ~15 d of the ~25 d superoutburst, as…
(Abridged) We report on the analysis of high-speed photometry of the dwarf nova EX Dra through its outburst cycle with eclipse mapping techniques. The eclipse maps show evidence of the formation of a one-armed spiral structure in the disc…
X-ray binary accretion disk winds can carry away a significant fraction of the matter transferred from the companion and hence strongly affect the accretion flow and the long-term evolution of the binary. However, accurate mass outflow rate…
1RXS J180408.9-342058 is a transient neutron star low-mass X-ray binary that exhibited a bright accretion outburst in 2015. We present Nustar, Swift, and Chandra observations obtained around the peak of this outburst. The source was in a…
The first VLBI images of water maser emission in the Circinus Galaxy AGN show both an accretion disk and outflow 0.1 to 1 pc from the central engine. The maser traces a warped, edge-on accretion disk between radii of about 0.1 and 0.4 pc…
The outburst cycles of black hole X-ray transients are now generally understood as caused by a thermal instability in the accretion disk, the same mechanism as in dwarf novae outbursts. During quiescence the accretion occurs via a cool disk…
Type I X-ray bursts and superbursts on neutron stars release sudden and intense radiation fields into their surroundings. Here, we consider the possible effects of these powerful explosions on the structure of the accretion disk. The goal…
Neutrino-cooled accretion flow around a spinning black hole, produced by a compact binary merger is a promising scenario for jet formation and launching magnetically-driven outflows. Based on GW170817 gravitational wave detection by LIGO…
Powerful outflows along the accretion disk, known as disk winds, are sometimes launched in black hole X-ray binaries. These winds often manifest themselves in X-ray spectra as blueshifted, highly ionized absorption lines. Previous…
A strong outburst of the X-ray transient V404 Cygni (= GS2023-338) was observed in 2015 June/July up to a level of 50 Crab in the hard X-ray domain. At this level of photon flux, an instrument's behavior may be severely tested and some…
Observed IR excesses indicate that protoplanetary discs evolve slowly for the majority of their lifetime before losing their near- and mid-IR excesses on short timescales. Photoevaporation models can explain this "two-timescale" nature of…
Transient X-ray binaries produce major outbursts in which the X-ray flux can increase over the quiescent level by factors as large as $10^7$. The low-mass X-ray binary V 404 Cyg and the high-mass system 4U 0115+634 underwent such major…