226 citations · 703 across the 31 of their papers we have counts for
32 papers
A Multi-Wavelength Picture of the Surprisingly Short 2024/25 Outburst from EXO 0748-676
Amy H. Knight, Lauren Rhodes, Noel Castro Segura +11
After sixteen years in quiescence, EXO 0748-676 unexpectedly returned to outburst in March 2024. However, in stark contrast to its previous outburst (1985 - 2008), EXO 0748-676 ret…
On the frequency-dependent time lags of the intermediate polar V709 Cas
Zackery A. Irving, Noel Castro Segura, Diego Altamirano +9
Cataclysmic variables (CVs) are binary systems in which a white dwarf (WD) primary accretes material from a late-type secondary, typically via a disc. To date, only six CVs, all of…
phoptic -- a Python package for reducing astronomical images
Zackery A. Irving, Noel Castro Segura, Diego Altamirano +6
Publicly-available photometry pipelines make astronomical data reduction accessible to non-experts, reduce the margin for human error, and enable reproducible reduction. In many ca…
An eclipsing 8.56 minute orbital period mass-transferring binary
Emma T. Chickles, Joheen Chakraborty, Kevin B. Burdge +34
We report the discovery of ATLAS J101342.5-451656.8 (hereafter ATLAS J1013-4516), an 8.56 minute orbital period mass transferring AM Canum Venaticorum binary with mean Gaia magnitu…
Comprehensive Radio Monitoring of the Black Hole X-ray Binary Swift J1727.81613 during its 20232024 Outburst
Andrew K. Hughes, Francesco Carotenuto, Thomas D. Russell +39
This work presents comprehensive multi-frequency radio monitoring of the black hole low-mass X-ray binary Swift J1727.81613, which underwent its first recorded outburst after it…
Ultraviolet spectroscopy of the black hole X-ray binary MAXI J1820+070 across a state transition
Maria Georganti, Christian Knigge, Noel Castro Segura +8
We present ultraviolet (UV) spectroscopic observations covering three distinct accretion states of the low-mass X-ray binary (LMXB) MAXI J1820+070: the luminous hard state, a hard-…
Expanding the ultracompacts: gravitational wave-driven mass transfer in the shortest-period binaries with accretion disks
Joheen Chakraborty, Kevin B. Burdge, Saul A. Rappaport +35
We report the discovery of three ultracompact binary white dwarf systems hosting accretion disks, with orbital periods of 7.95, 8.68, and 13.15 minutes. This significantly augments…
Simultaneous Optical and X-ray Detection of a Thermonuclear Burst in the 2024 Outburst of EXO 0748-676
Amy H. Knight, Lauren Rhodes, Douglas J. K. Buisson +5
The neutron star low-mass X-ray binary, EXO 0748--676, recently returned to outburst after a 16 year-long quiescence. Since its return, there has been a global effort to cap…
Analysis of optical spectroscopy and photometry of the type I X-ray bursting system UW CrB
M. R. Kennedy, P. Callanan, P. M. Garnavich +19
UW Coronae Borealis (UW CrB) is a low mass X-ray binary that shows both Type 1 X-ray and optical bursts, which typically last for 20 s. The system has a binary period of close to 2…
A disc wind origin for the optical spectra of dwarf novae in outburst
Yusuke Tampo, Christian Knigge, Knox S. Long +2
Many high-state cataclysmic variables (CVs) exhibit blue-shifted absorption features in their ultraviolet (UV) spectra -- a smoking-gun signature of outflows. However, the impact o…
Quasi-isotropic UV Emission in the ULX NGC~1313~X--1
Andrés Gúrpide, Noel Castro Segura
A major prediction of most super-Eddington accretion theories is the presence of anisotropic emission from supercritical disks, but the degree of anisotropy and its dependency with…
Absence of nebular He{\sc ii} 4686 constrains the UV emission from the Ultraluminous X-ray pulsar NGC~1313~X--2
Andrés Gúrpide, Noel Castro Segura, Roberto Soria +1
While much has been learned in recent decades about the X-ray emission of the extragalactic Ultraluminous X-ray sources (ULXs), their radiative output in the UV band remains poorly…
Recovery of the X-ray polarisation of Swift J1727.81613 after the soft-to-hard spectral transition
J. Podgorný, J. Svoboda, M. Dovčiak +34
We report on the detection of X-ray polarisation in the black-hole X-ray binary Swift J1727.81613 during its dim hard spectral state by the Imaging X-ray Polarimetry Explorer (I…
Rapid dimming followed by a state transition: a study of the highly variable nuclear transient AT 2019avd over 1000+ days
Yanan Wang, Dheeraj R. Pasham, Diego Altamirano +16
The tidal disruption of a star around a supermassive black hole (SMBH) offers a unique opportunity to study accretion onto a SMBH on a human-timescale. We present results from our…
Shedding far-ultraviolet light on the donor star and evolutionary state of the neutron-star LMXB Swift J1858.6-0814
N. Castro Segura, C. Knigge, J. H. Matthews +13
The evolution of accreting X-ray binary systems is closely coupled to the properties of their donor stars. As a result, we can constrain the evolutionary track a system is by estab…
The innermost jet in the hidden ultra-luminous X-ray source Cygnus X-3
Jun Yang, Federico García, Santiago del Palacio +6
Cygnus X-3 is a high-mass X-ray binary with a compact object accreting matter from a Wolf-Rayet donor star. Recently, it has been revealed by the Imaging X-ray Polarimetry Explorer…
Variability and evolution of the optical polarization of a sample of gamma-ray blazars
J. Otero-Santos, J. A. Acosta-Pulido, J. Becerra González +5
We present a polarization variability analysis of a sample of 26 -ray blazars monitored by the Steward Observatory between 2008 and 2018 in the optical band. We investigate the…
A transient ultraviolet outflow in the short-period X-ray binary UW CrB
S. Fijma, N. Castro Segura, N. Degenaar +4
Accreting low mass X-ray binaries (LMXBs) are capable of launching powerful outflows such as accretion disc winds. In disc winds, vast amounts of material can be carried away, pote…
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…
The radio detection and accretion properties of the peculiar nuclear transient AT 2019avd
Yanan Wang, Ranieri D. Baldi, Santiago del Palacio +19
AT 2019avd is a nuclear transient detected from infrared to soft X-rays, though its nature is yet unclear. The source has shown two consecutive flaring episodes in the optical and…
A statistical study of the optical spectral variability in gamma-ray blazars
J. Otero-Santos, J. A. Acosta-Pulido, J. Becerra González +5
Blazars optical emission is generally dominated by relativistic jets, although the host galaxy, accretion disk and broad line region (BLR) may also contribute significantly. Disent…
Discovery of thermonuclear (Type I) X-ray bursts in the X-ray binary Swift J1858.6-0814 observed with NICER and NuSTAR
D. J. K. Buisson, D. Altamirano, P. Bult +22
Swift J1858.6-0814 is a recently discovered X-ray binary notable for extremely strong variability (by factors in soft X-rays) in its discovery state. We present the detectio…
Bow-shocks, nova shells, disc winds and tilted discs: The Nova-Like V341 Ara Has It All
N. Castro Segura, C. Knigge, J. A. Acosta-Pulido +21
V341 Ara was recently recognised as one of the closest (d ~ 150 pc) and brightest (V~ 10) nova-like cataclysmic variables. This unique system is surrounded by a bright emission neb…
Soft X-ray emission lines in the X-ray binary Swift J1858.6-0814 observed with XMM-Newton-RGS: disc atmosphere or wind?
D. J. K. Buisson, D. Altamirano, M. Díaz Trigo +11
We find soft X-ray emission lines from the X-ray binary Swift J1858.6-0814 in data from XMM-Newton-RGS: N VII, O VII and O VIII, as well as notable residuals short of a detection a…