Search Publications
Further support for a trio of mass-to-light deviations in Abell 370: free-form GRALE lens inversion using BUFFALO strong lensing data
Koekemoer, Anton M.; Mahler, Guillaume; Acebron, Ana +9 more
We use the Beyond Ultra-deep Frontier Fields and Legacy Observations (BUFFALO) strong lensing image catalogue of the merging galaxy cluster Abell 370 to obtain a mass model using free-form lens inversion algorithm GRALE. The improvement of the strong lensing data quality results in a lens plane rms of only 0.45 arcsec, about a factor of two lower …
Testing the evolution of correlations between supermassive black holes and their host galaxies using eight strongly lensed quasars
Treu, Tommaso; Auger, Matthew W.; Birrer, Simon +9 more
One of the main challenges in using high-redshift active galactic nuclei (AGNs) to study the correlations between the mass of a supermassive black hole ($\mathcal {M}_{\rm BH}$) and the properties of its active host galaxy is instrumental resolution. Strong lensing magnification effectively increases instrumental resolution and thus helps to addre…
A test of the planet-star unipolar inductor for magnetic white dwarfs
Hermes, J. J.; Marsh, T. R.; Bagnulo, S. +7 more
Despite thousands of spectroscopic detections, only four isolated white dwarfs exhibit Balmer emission lines. The temperature inversion mechanism is a puzzle over 30 years old that has defied conventional explanations. One hypothesis is a unipolar inductor that achieves surface heating via ohmic dissipation of a current loop between a conducting p…
Forward modelling of Kepler-band variability due to faculae and spots
Solanki, Sami K.; Shapiro, Alexander I.; Krivova, Natalie +4 more
Variability observed in photometric light curves of late-type stars (on time-scales longer than a day) is a dominant noise source in exoplanet surveys and results predominantly from surface manifestations of stellar magnetic activity, namely faculae and spots. The implementation of faculae in light-curve models is an open problem, with scaling typ…
Galactic extinction laws - II. Hidden in plain sight, a new interstellar absorption band at 7700 Å broader than any known DIB
Caballero, J. A.; Bohlin, R. C.; Maíz Apellániz, J. +2 more
We have detected a broad interstellar absorption band centred close to 7700 Å and with a full width at half-maximum (FWHM) of 176.6 ± 3.9 Å. This is the first such absorption band detected in the optical range and is significantly wider than the numerous diffuse interstellar bands (DIBs). It remained undiscovered until now because it is partially …
A search for variable subdwarf B stars in TESS Full Frame Images - II. Variable objects in the northern ecliptic hemisphere
Sahoo, S. K.; Baran, A. S.; Ostrowski, J. +1 more
We report the results of our search for pulsating subdwarf B stars in Full Frame Images collected during Year 2 of the TESS mission and covering the northern ecliptic hemisphere. This is a continuation of our effort we presented in Paper I. We found 13 likely new pulsating subdwarf B stars, 10 pulsating candidates that are identified as other hot …
ASKAP observations of multiple rapid scintillators reveal a degrees-long plasma filament
Kaplan, David L.; Lenc, Emil; Murphy, Tara +5 more
We present the results from an Australian Square Kilometre Array Pathfinder search for radio variables on timescales of hours. We conducted an untargeted search over a 30 deg2 field, with multiple 10-h observations separated by days to months, at a central frequency of 945 MHz. We discovered six rapid scintillators from 15-min model-sub…
The HST large programme on ω Centauri - IV. Catalogue of two external fields
Salaris, M.; Apai, D.; Anderson, J. +9 more
In the fourth paper of this series, we present - and publicly release - the state-of-the-art catalogue and atlases for the two remaining parallel fields observed with the Hubble Space Telescope for the large programme on ω Centauri. These two fields are located at ~12 arcmin from the centre of the globular cluster (in the west and south-west direc…
Optimized modelling of Gaia-Hipparcos astrometry for the detection of the smallest cold Jupiter and confirmation of seven low-mass companions
Butler, R. Paul; Vogt, Steven S.; Oppenheimer, Rebecca +6 more
To fully constrain the orbits of low-mass circumstellar companions, we conduct combined analyses of the radial velocity data and the Gaia and Hipparcos astrometric data for eight nearby systems. Our study shows that companion-induced position and proper motion differences between Gaia and Hipparcos are significant enough to constrain orbits of low…
The Gaia spectrophotometric standard stars survey - V. Preliminary flux tables for the calibration of Gaia DR2 and (E)DR3
Harrison, D. L.; Jordi, C.; Rainer, M. +15 more
We present the flux tables of the spectrophotometric standard stars (SPSS) used to calibrate in flux the Gaia DR2 and (E)DR3 data releases. The latest SPSS grid version contains 112 stars, whose flux tables agree to better than 1 per cent with the CALSPEC spectra of 11 flux standards for the calibration of the Hubble Space Telescope. The synthetic…