Related papers: Radio Variability from a Quiescent Stellar Mass Bl…

We present results from multi-wavelength simultaneous X-ray and radio observations of the black hole X-ray binary V404 Cyg in quiescence. Our coverage with NuSTAR provides the very first opportunity to study the X-ray spectrum of V404 Cyg…

We present simultaneous X-ray and radio observations of the black hole X-ray binary V404 Cygni at the end of its 2015 outburst. From 2015 July 11-August 5 we monitored V404 Cygni with Chandra, Swift, and NuSTAR in the X-ray, and with the…

We conducted the first long-term (75 days) X-ray monitoring of the black hole low mass X-ray binary V404 Cyg, with the goal of understanding and characterizing its variability during quiescence. The X-ray light curve of V404 shows several…

Observations of V404 Cyg performed with the Westerbork Synthesis Radio Telescope at four frequencies, over the interval 1.4-8.4 GHz, have provided us with the first broadband radio spectrum of a `quiescent' stellar mass black hole. The…

Weakly accreting black hole X-ray binaries launch compact radio jets that persist even in the quiescent spectral state, at X-ray luminosities <1e-5 of the Eddington luminosity. However, radio continuum emission has been detected from only a…

We present multi-frequency monitoring observations of the black hole X-ray binary V404 Cygni throughout its June 2015 outburst. Our data set includes radio and mm/sub-mm photometry, taken with the Karl G. Jansky Very Large Array, Arc-Minute…

Observations of some quiescent black hole X-ray binaries have revealed an excess of mid-infrared (MIR) emission above that expected from their donor stars. In one system, V404 Cygni, this excess has been variously suggested to arise from…

We report results of Chandra X-ray and VLA radio observations of the Galactic accreting black hole V404 Cyg (GS 2023+338) in its quiescent state. V404 Cyg is detected at its faintest level of radio and X-ray emission with a 0.5-10 keV…

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 present simultaneous radio through sub-mm observations of the black hole X-ray binary (BHXB) V404 Cygni during the most active phase of its June 2015 outburst. Our $4$ hour long set of overlapping observations with the Very Large Array,…

We present simultaneous multi-band radio and X-ray observations of the black hole X-ray binary Cygnus X-1, taken with the Karl G. Jansky Very Large Array and the Nuclear Spectroscopic Telescope Array. With these data, we detect clear flux…

We present a comprehensive study of (quasi-)simultaneous radio:X-ray observations of stellar black hole binaries during the spectrally hard X-ray state, finding evidence for a strong correlation between these two bands over more than three…

Waseda University Nasu telescope array is a spatial fast Fourier transform (FFT) interferometer consisting of eight linearly aligned antennas with 20 m spherical dishes. This type of interferometer was developed to survey transient radio…

We present analysis of comprehensive radio observations of the black hole V404 Cyg during its 2015 outburst. These data represent the best ever coverage of jet production and particle acceleration from any black hole. We report for the…

We present XMM observations of the black hole X-ray nova V404 Cygni in quiescence. Its quiescent spectrum can be best fitted by a simple power-law with slope 2. The spectra are consistent with that expected for the advection-dominated…

We present a spectrophotometric study of short-term optical variability in the quiescent black hole X-ray transient V404 Cyg focusing on two nights of Halpha spectroscopy. We find significant variability, with both the Halpha line and the…

We present a multiwavelength study of the black hole X-ray binary V404 Cyg in quiescence, focusing upon the spectral energy distribution (SED). Radio, optical, UV, and X-ray coverage is simultaneous. We supplement the SED with additional…

We present a spectrophotometric study of short-term optical variability in the quiescent black hole X-ray transient V404 Cyg. This includes two nights of high time-resolution Halpha spectroscopy with which we resolve much of the…

20 months of observations of the radio emission at 15 GHz from Cygnus X-1, starting in 1996 October, show variations at the binary period of 5.6 days, but with a phase offset from those at X-ray wavelengths. There are also longer-term…

Observations of the black hole X-ray binary V404 Cyg with the very long baseline interferometer HSA (the High Sensitivity Array) have detected the source at a frequency of 8.4 GHz, providing a source position accurate to 0.3 mas relative to…