Related papers: The stringent upper limit on jet power in the pers…
We present a unified semi-quantitative model for the disc-jet coupling in black hole X-ray binary systems. We argue that during the rising phase of a black hole transient outburst the steady jet known to be associated with the canonical…
We present the results of a weekly monitoring of the new black hole candidate X-ray binary MAXI J1631-472 carried out with the MeerKAT radio interferometer, the Neil Gehrels Swift Observatory, and the Monitor of All-sky X-ray Image (MAXI)…
The three X-ray states of active accretion in black-hole binaries have been re-defined to focus attention on different physical elements that may contribute radiation: the accretion disk, a jet, and a compact and radio-quiet corona.…
We have conducted a deep radio survey of a sample of black hole X-ray binaries in the hard and quiescent states, to determine whether any systems were sufficiently bright for astrometric follow-up with high-sensitivity very long baseline…
We present an X-ray spectral and timing analysis of 4U 1543-47 during its 2002 outburst based on 49 pointed observations obtained using the Rossi X-ray Timing Explorer (RXTE). The outburst reached a peak intensity of 4.2 Crab in the 2-12…
We report on radio and X-ray monitoring observations of the BHC Swift J1753.5-0127 taken over a ~10 year period. Presented are daily radio observations at 15 GHz with the AMI-LA and X-ray data from Swift XRT and BAT. Also presented is a…
Black holes in binary systems execute patterns of outburst activity where two characteristic X-ray states are associated with different behaviours observed at radio wavelengths. The hard state is associated with radio emission indicative of…
We studied the relation of accretion-jet power and disk luminosity, especially the jet efficiencies and disk radiative efficiencies for different accretion disks as well as black hole (BH) spin, in order to explore the origin of radio…
We present results from six epochs of quasi-simultaneous radio, (sub-)millimetre, infrared, optical, and X-ray observations of the black hole X-ray binary MAXI~J1535$-$571. These observations show that as the source transitioned through the…
(Abridged) We present a comprehensive study of the relation between radio and X-ray emission in neutron star X-ray binaries, use this to infer the general properties of the disc-jet coupling in such systems, and compare the results…
The most extreme ultraluminous X-ray sources (ULXs), with $L_\mathrm{X} > 5 \times 10^{40}$ erg s$^{-1}$, are amongst the best candidates for hosting intermediate-mass black holes (IMBHs) in the haloes of galaxies. Jet radio emission is…
We have analysed 12 simultaneous radio (VLA) and X-ray (RXTE) observations of the atoll-type X-ray binary 4U 1728-34, performed in two blocks in 2000 and 2001. We have found that the strongest and most variable emission seems to be…
Relativistic jets powered by stellar mass black holes in X-ray binaries appear to come in two types: steady outflows associated with hard X-ray states and large scale discrete ejections associated with transient outbursts. We show that the…
We present the X-ray spectral and timing analysis of the transient black hole X-ray binary 4U 1630-47, observed with the AstroSat, Chandra and MAXI space missions during its soft X-ray outburst in 2016. The outburst, from the rising phase…
We present the results of our quasi-simultaneous radio, sub-mm, infrared, optical and X-ray study of the Galactic black hole candidate X-ray binary MAXI J1836-194 during its 2011 outburst. We consider the full multi-wavelength spectral…
We study long-term radio/X-ray correlations in Cyg X-1. We find the persistent existence of a compact radio jet in its soft state. This represents a new phenomenon in black-hole binaries, in addition to compact jets in the hard state and…
We explore the evolution in power of black holes of all masses, and their associated jets, within the scheme of an accretion rate-dependent state transition. Below a critical value of the accretion rate all systems are assumed to undergo a…
We present the analysis of simultaneous X-ray (RXTE) and radio (VLA) observations of two atoll-type neutron star X-ray binaries: 4U 1820-30 and Ser X-1. Both sources were steadily in the soft (banana) X-ray state during the observations. We…
The black hole candidate (BHC) X-ray transient 4U 1630-47 continuously produced strong X-ray emission for over 2 years during 2002-2004. We use observations made with the Rossi X-ray Timing Explorer (RXTE) to study the source throughout the…
This article reports on a growing body of observational evidence that many powerful lobe dominated (FR II) radio sources likely have jets with high efficiency. This study extends the maximum efficiency line (jet power $\approx$ 25 times the…