Search Publications
The Million Quasars (Milliquas) Catalogue, v8
Flesch, Eric Wim
Announcing the final release, v8, of the Milliquas (Million Quasars) quasar catalogue which presents all published quasars to 30 June 2023, including quasars from the first releases of the Dark Energy Spectroscopic Instrument (DESI) and the SDSS-DR18 Black Hole Mapper. Its totals are 907,144 type-I QSOs/AGN and 66,026 high-confidence (~99% likelih…
The fastest stars in the Galaxy
Roulston, Benjamin R.; Filippenko, Alexei V.; Strader, Jay +17 more
We report a spectroscopic search for hypervelocity white dwarfs (WDs) that are runaways from Type Ia supernovae (SNe Ia) and related thermonuclear explosions. Candidates are selected from Gaia data with high tangential velocities and blue colors. We find six new runaways, including four stars with radial velocities (RVs) $>1000\,\rm km\,s^{-1}$…
Wide Binaries from GAIA EDR3: preference for GR over MOND?
Sutherland, Will; Pittordis, Charalambos
Several recent studies have shown that velocity differences of very wide binary stars, measured to high precision with GAIA, can potentially provide an interesting test for modified-gravity theories which attempt to emulate dark matter. These systems should be entirely Newtonian according to standard dark-matter theories, while the predictions for…
Wide Binaries as a Modified Gravity test: prospects for detecting triple-system contamination
Manchanda, Dhruv; Sutherland, Will; Pittordis, Charalambos
Recent studies have shown that velocity differences of very wide binary stars, measured to high precision with GAIA, can provide an interesting test for modified-gravity theories which emulate dark matter; in essence, MOND-like theories (with external field effect included) predict that wide binaries (wider than ~ 7 kAU) should orbit ~ 15% faster …
A transiting brown dwarf in a 2 hour orbit
El-Badry, Kareem; Burdge, Kevin B.; Rodriguez, Antonio C. +1 more
We report the discovery of ZTF J2020+5033, a high-mass brown dwarf (BD) transiting a low-mass star with an orbital period of 1.90 hours. Phase-resolved spectroscopy, optical and infrared light curves, and precise astrometry from Gaia allow us to constrain the masses, radii, and temperatures of both components with few-percent precision. We infer a…