141 citations · 2.1k across the 72 of their papers we have counts for
58 papers · 1 filter
Superorbital variability in the quiescent black hole X-ray transient A0620-00
Enzo A. Saavedra, Roi Alonso, Teo Muñoz-Darias +10
Quiescent black hole low-mass X-ray binaries provide a key setting for probing accretion physics at low luminosities. A0620-00, the archetypal system in this class, has remained in…
Resolving SLX 1744-299 and SLX 1744-300 in the hard X-ray band: implications for their ultracompact nature
Enzo A. Saavedra, Montserrat Armas Padilla, Teo Muñoz-Darias
Persistent, low-luminosity low-mass X-ray binaries (LMXBs) offer a unique opportunity to study accretion in this poorly understood regime, as well as to unveil new members of the u…
The NuSTAR view of Ultra-Compact X-ray Binaries
A. Borghese, M. Armas Padilla, T. Muñoz-Darias
Ultra-compact X-ray binaries (UCXBs) are a subclass of low-mass X-ray binaries (LMXBs) characterised by tight orbits and hydrogen-poor donor stars. We present a spectral and timing…
Ubiquitous yet forgotten: broad absorptions in the optical spectra of low-mass X-ray binaries
D. Mata Sanchez, T. Munoz-Darias, J. Casares +2
Optical outburst spectra of low-mass X-ray binaries enable studies of extreme accretion and ejection phenomena. While some of their spectroscopic features have been analysed in det…
XRISM reveals a variable, multi-phase outflow-inflow structure during the X-ray obscured 2024 outburst of the black hole transient V4641 Sgr
Maxime Parra, Megumi Shidatsu, Ryota Tomaru +23
We report the results of a simultaneous X-ray and optical spectroscopy campaign on the Galactic black hole X-ray binary V4641 Sgr, carried out with XRISM and the Seimei telescope d…
The orbital period and inclination of the neutron star X-ray transient MAXI J1807+132
E. A. Saavedra, T. Muñoz-Darias, M. A. P. Torres +7
The neutron star X-ray transient MAXI J1807+132 has undergone outbursts in 2017, 2019, and 2023. We conducted an -band time series photometry campaign using the Isaac Newton Tel…
Radio Continuum Studies of Ultra-Compact and Short Orbital Period X-Ray Binaries
Kristen C. Dage, Teresa Panurach, Kwangmin Oh +14
We present the radio continuum counterparts to the enigmatic ultra-compact X-ray binaries (UCXBs); a black hole or neutron star accreting from a hydrogen-deficient white dwarf dono…
A Multi-wavelength Characterization of the 2023 Outburst of MAXI J1807+132: Manifestations of Disk Instability and Jet Emission
Sandeep K. Rout, M. Cristina Baglio, Andrew Hughes +19
Several phenomenological aspects of low-luminosity neutron star transients, such as atolls, remain poorly understood. One such source, MAXI J1807+132, entered its latest outburst i…
On the nature of the X-ray binary transient MAXI J1834-021: clues from its first observed outburst
A. Manca, A. Marino, A. Borghese +14
MAXI J1834-021 is a new X-ray transient that was discovered in February 2023. We analysed the spectral and timing properties of MAXI J1834-021 using NICER, NuStar and Swift data co…
Revisiting the fundamental parameters for the black hole X-ray transient Swift J1753.5-0127
I. V. Yanes-Rizo, M. A. P. Torres, J. Casares +4
We present time-resolved Gran Telescopio Canarias optical spectroscopy and William Herschel Telescope -band photometry of the X-ray transient SWIFT J1753.5-0127 in quiescence. T…
Detection of extended X-ray emission around the PeVatron microquasar V4641 Sgr with XRISM
Hiromasa Suzuki, Naomi Tsuji, Yoshiaki Kanemaru +26
A recent report on the detection of very-high-energy gamma rays from V4641 Sagittarii (V4641 Sgr) up to ~0.8 peta-electronvolt has made it the second confirmed "PeVatron" microquas…
X-ray observations of the very-faint X-ray transient XMMSL1 J171900.4--353217: A new candidate neutron star low-mass X-ray binary
O. Ahmed, N. Degenaar, R. Wijnands +1
XMMSL1 J171900.4-353217 is a very-faint X-ray transient that was discovered in 2010 March when it exhibited an outburst. We report on 7 observations, obtained with the X-Ray Telesc…
Dynamical confirmation of a black hole in the X-ray transient Swift J1727.8-1613
D. Mata Sanchez, M. A. P. Torres, J. Casares +3
The X-ray transient Swift J1727.8-1613 ended its 10-month discovery outburst on June of 2024, when it reached an optical brightness comparable to pre-discovery magnitudes. With the…
Evidence for inflows and outflows in the nearby black hole transient Swift J1727.8-162
D. Mata Sánchez, T. Muñoz-Darias, M. Armas Padilla +2
We present 20 epochs of optical spectroscopy obtained with the GTC-10.4m telescope across the bright discovery outburst of the black hole candidate Swift J1727.8-162. The spectra c…
Fast infrared winds during the radio-loud and X-ray obscured stages of the black hole transient GRS 1915+105
J. Sánchez-Sierras, T. Muñoz-Darias, S. E. Motta +10
The black hole transient GRS 1915+105 entered a new phase of activity in 2018, generally characterised by low X-ray and radio fluxes. This phase has been only interrupted by episod…
Evidence for a black hole in the historical X-ray transient A 1524-61 (=KY TrA)
I. V. Yanes-Rizo, M. A. P. Torres, J. Casares +5
We present VLT spectroscopy, high-resolution imaging and time-resolved photometry of KY TrA, the optical counterpart to the X-ray binary A 1524-61. We perform a refined astrometry…
The omnipresent flux-dependent optical dips of the black hole transient Swift J1357.2-0933
G. Panizo-Espinar, T. Muñoz-Darias, M. Armas Padilla +15
Swift J1357.2-0933 is a black hole transient of particular interest due to the optical, recurrent dips found during its first two outbursts (in 2011 and 2017), with no obvious X-ra…
An infrared FWHM- correlation to uncover highly reddened quiescent black holes
V. A. Cúneo, J. Casares, M. Armas Padilla +7
Among the sample of Galactic transient X-ray binaries (SXTs) discovered to date, about 70 have been proposed as likely candidates to host a black hole. Yet, only 19 have been dynam…
H spectroscopy of the high-inclination black hole transient Swift J1357.2-0933 during quiescence
A. Anitra, D. Mata Sanchez, T. Munoz-Darias +6
Swift J1357.2-0933 is a transient low-mass X-ray binary hosting a stellar-mass black hole. The source exhibits optical dips and very broad emission lines during both outburst and q…
The orbital period, black hole mass and distance to the X-ray transient GRS 1716-249 (=N Oph 93)
J. Casares, I. V. Yanes-Rizo, M. A. P. Torres +7
We present evidence for a 0.278(8) d (=6.7 h) orbital period in the X-ray transient GRS 1716-249 (=N Oph 93), based on a superhump modulation detected during the 1995 mini-outburst…
Sub-second infrared variability from the archetypal accreting neutron star 4U~1728-34
F. M. Vincentelli, P. Casella, A. Borghese +23
We report on the first simultaneous high-time resolution X-ray and infrared (IR) observations of a neutron star low mass X-ray binary in its hard state. We performed h…
UltraCompCAT: a comprehensive Catalogue of Ultra-Compact and Short Orbital Period X-ray Binaries
M. Armas Padilla, J. M. Corral-Santana, A. Borghese +4
Ultracompact X-ray binaries (UCXBs) are a distinctive but elusive family of low-mass X-ray binaries (LMXBs) characterised by their tight orbits and degenerate donor stars. Here we…
Optical and near-infrared spectroscopy of the black hole transient 4U 1543-47 during its 2021 ultra-luminous state
J. Sánchez-Sierras, T. Muñoz-Darias, J. Casares +10
We present simultaneous optical and near-infrared spectra obtained during the 2021 outburst of the black hole transient 4U 1543-47. The X-ray hardness-intensity diagram and the com…
A shared accretion instability for black holes and neutron stars
F. M. Vincentelli, J. Neilsen, A. J. Tetarenko +20
Accretion disks around compact objects are expected to enter an unstable phase at high luminosity. One instability may occur when the radiation pressure generated by accretion modi…