-
1
THE TRIGONOMETRIC PARALLAX OF CYGNUS X-1
Published 2015“…We report a direct and accurate measurement of the distance to the X-ray binary Cygnus X-1, which contains the first black hole to be discovered. …”
Get full text
Article -
2
THE MASS OF THE BLACK HOLE IN CYGNUS X-1
Published 2015“…Cygnus X-1 is a binary star system that is comprised of a black hole and a massive giant companion star in a tight orbit. …”
Get full text
Article -
3
Spectroscopy of the Stellar Wind in the Cygnus X-1 System
Published 2011-01-01Subjects: Get full text
Article -
4
THE EXTREME SPIN OF THE BLACK HOLE IN CYGNUS X-1
Published 2015“…The compact primary in the X-ray binary Cygnus X-1 was the first black hole to be established via dynamical observations. …”
Get full text
Article -
5
Search for ultralight bosons in Cygnus X-1 with Advanced LIGO
Published 2020“…Here we present results of a directed search for such signals from the Cygnus X-1 binary, using data from Advanced LIGO’s second observing run. …”
Get full text
Article -
6
An X-ray reverberation mass measurement of Cygnus X-1
Published 2019“…We jointly fit the time-averaged spectrum and the real and imaginary parts of the cross-spectrum as a function of energy for a range of Fourier frequencies to Rossi X-ray Timing Exporer data from the X-ray binary Cygnus X-1. We also show that introducing a self-consistently calculated radial ionisation profile in the disc improves the fit, but requires us to impose an upper limit on ionization profile peak to allow a plausible value of the accretion disc density. …”
Journal article -
7
-
8
The high-energy spectrum of Cygnus X–1: corona and jet contributions
Published 2013-12-01“…We have analyzed six years of INTEGRAL observations of the BH binary Cygnus X-1. We report on the evolution of the physical parameters of the accretion flow across spectral transitions. …”
Get full text
Article -
9
The reflection component from Cygnus X-1 in the soft state measured by Nustar and Suzaku
Published 2015“…The black hole binary Cygnus X-1 was observed in late 2012 with the Nuclear Spectroscopic Telescope Array (NuSTAR) and Suzaku, providing spectral coverage over the ~1-300 keV range. …”
Get full text
Article -
10
CONFIRMATION VIA THE CONTINUUM-FITTING METHOD THAT THE SPIN OF THE BLACK HOLE IN CYGNUS X-1 IS EXTREME
Published 2015“…In Gou et al., we reported that the black hole primary in the X-ray binary Cygnus X-1 is a near-extreme Kerr black hole with a spin parameter a * > 0.95 (3σ). …”
Get full text
Article -
11
USING THE X-RAY DUST SCATTERING HALO OF CYGNUS X-1 TO DETERMINE DISTANCE AND DUST DISTRIBUTIONS
Published 2015“…We present a detailed study of the X-ray dust scattering halo of the black hole candidate Cygnus X-1 based on two Chandra High Energy Transmission Gratings Spectrometer observations. …”
Get full text
Article -
12
NuSTAR AND SUZAKU OBSERVATIONS OF THE HARD STATE IN CYGNUS X-1: LOCATING THE INNER ACCRETION DISK
Published 2015“…We present simultaneous Nuclear Spectroscopic Telescope Array (NuSTAR ) and Suzaku observations of the X-ray binary Cygnus X-1 in the hard state. This is the first time this state has been observed in Cyg X-1 with NuSTAR, which enables us to study the reflection and broadband spectra in unprecedented detail. …”
Get full text
Get full text
Article -
13
High-resolution X-Ray Spectroscopy of Interstellar Iron toward Cygnus X-1 and GX 339-4
Published 2024-01-01“…We present a high-resolution spectral study of Fe L -shell extinction by the diffuse interstellar medium (ISM) in the direction of the X-ray binaries Cygnus X-1 and GX 339–4, using the XMM-Newton reflection grating spectrometer. …”
Get full text
Article -
14
THE SOFT STATE OF CYGNUS X-1 OBSERVED WITH NuSTAR: A VARIABLE CORONA AND A STABLE INNER DISK
Published 2016“…We present a multi-epoch hard X-ray analysis of Cygnus X-1 in its soft state based on four observations with the Nuclear Spectroscopic Telescope Array (NuSTAR). …”
Get full text
Get full text
Article -
15
-
16
CHANDRA X-RAY SPECTROSCOPY OF THE FOCUSED WIND IN THE CYGNUS X-1 SYSTEM. I. THE NONDIP SPECTRUM IN THE LOW/HARD STATE
Published 2015“…We present analyses of a 50 ks observation of the supergiant X-ray binary system Cygnus X-1 (Cyg X-1)/HDE226868 taken with the Chandra High Energy Transmission Grating Spectrometer (HETGS). …”
Get full text
Article -
17
High Hard X-Ray Polarization in Cygnus X-1 Confined to the Intermediate Hard State: Evidence for a Variable Jet Component
Published 2023-01-01“…We examine the possible sources of this energy-dependent high polarization in Cygnus X-1.…”
Get full text
Article -
18
An IXPE-led X-Ray Spectropolarimetric Campaign on the Soft State of Cygnus X-1: X-Ray Polarimetric Evidence for Strong Gravitational Lensing
Published 2024“…We present the first X-ray spectropolarimetric results for Cygnus X-1 in its soft state from a campaign of five IXPE observations conducted during 2023 May–June. …”
Journal article -
19
SPECTRAL STATE DEPENDENCE OF THE 0.4–2 MEV POLARIZED EMISSION IN CYGNUS X-1 SEEN WITH INTEGRAL/IBIS, AND LINKS WITH THE AMI RADIO DATA
Published 2015“…Polarization of the [> over ~] 400 keV hard tail of the microquasar Cygnus X-1 has been independently reported by INTEGRAL/Imager on Board the INTEGRAL Satellite (IBIS), and INTEGRAL/SPectrometer on INTEGRAL and interpreted as emission from a compact jet. …”
Get full text
Get full text
Article -
20
Tracing Black Hole Signatures in Several Black Hole Candidates Based on Their X-Ray Spectral Evolution
Published 2020-01-01“…The spectral evolutions of the candidates bear a resemblance to both Cygnus X-1 and XTE J1752-223. We note that during Swift/XRT observations, the spectra of Cygnus X-1 and IGR J17451-3022 are mostly dominated by the non- thermal component. …”
Get full text
Article