Search Publications
MIGHTEE: the nature of the radio-loud AGN population
Prandoni, I.; Bowler, R. A. A.; Marchetti, L. +24 more
We study the nature of the faint radio source population detected in the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) Early Science data in the COSMOS field, focusing on the properties of the radio-loud active galactic nuclei (AGNs). Using the extensive multiwavelength data available in the field, we are able to classify 88…
Primordial non-Gaussianity from the completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey II: measurements in Fourier space with optimal weights
Brownstein, Joel R.; Palanque-Delabrouille, Nathalie; Schneider, Donald P. +12 more
We present measurements of the local primordial non-Gaussianity parameter $f_{\mathrm{NL}}^\mathrm{local} $from the clustering of 343 708 quasars with redshifts 0.8 < z < 2.2 distributed over 4808 deg2 from the final data release (DR16) of the extended Baryon Acoustic Oscillation Spectroscopic Survey (eBOSS), the largest volume sp…
The GALAH Survey: dependence of elemental abundances on age and metallicity for stars in the Galactic disc
Lewis, Geraint F.; Buder, Sven; Lind, Karin +25 more
Using data from the GALAH survey, we explore the dependence of elemental abundances on stellar age and metallicity among Galactic disc stars. We find that the abundance of most elements can be predicted from age and [Fe/H] with an intrinsic scatter of about 0.03 dex. We discuss the possible causes for the existence of the abundance-age-metallicity…
VIA MACHINAE: Searching for stellar streams using unsupervised machine learning
Buckley, Matthew R.; Shih, David; Necib, Lina +1 more
We develop a new machine learning algorithm, VIA MACHINAE, to identify cold stellar streams in data from the Gaia telescope. VIA MACHINAE is based on ANODE, a general method that uses conditional density estimation and sideband interpolation to detect local overdensities in the data in a model agnostic way. By applying ANODE to the positions, prop…
Close detached white dwarf + brown dwarf binaries: further evidence for low values of the common envelope efficiency
Zorotovic, Monica; Schreiber, MatthiasR
Common envelope evolution is a fundamental ingredient in our understanding of the formation of close binary stars containing compact objects that include the progenitors of type Ia supernovae, short gamma-ray bursts, and most stellar gravitational wave sources. To predict the outcome of common envelope evolution, we still rely to a large degree on…
Discovery of 74 new bright ZZ Ceti stars in the first three years of TESS
Kepler, S. O.; Hermes, J. J.; Bell, Keaton J. +17 more
We report the discovery of 74 new pulsating DA white dwarf stars, or ZZ Cetis, from the data obtained by the Transiting Exoplanet Survey Satellite mission, from Sectors 1 to 39, corresponding to the first 3 cycles. This includes objects from the Southern hemisphere (Sectors 1-13 and 27-39) and the Northern hemisphere (Sectors 14-26), observed with…
Mapping the magnetic field in the Taurus/B211 filamentary cloud with SOFIA HAWC + and comparing with simulation
André, Philippe; Rho, Jeonghee; Li, Pak Shing +4 more
Optical and infrared polarization mapping and recent Planck observations of the filametary cloud L1495 in Taurus show that the large-scale magnetic field is approximately perpendicular to the long axis of the cloud. We use the HAWC + polarimeter on SOFIA to probe the complex magnetic field in the B211 part of the cloud. Our results reveal a disper…
The [O III]λ5007 equivalent width distribution at z 2: the redshift evolution of the extreme emission line galaxies
Maseda, Michael V.; Bunker, Andrew J.; Tang, Mengtao +2 more
We determine the [O III]λ5007 equivalent width (EW) distribution of $1.700\lt \rm {z}\lt 2.274$ rest-frame ultraviolet (UV)-selected (MUV < -19) star-forming galaxies in the GOODS North and South fields. We make use of deep HDUV broad-band photometry catalogues for selection and 3D-HST WFC3/IR grism spectra for measurement of line pr…
Intrinsic tension in the supernova sector of the local Hubble constant measurement and its implications
Hjorth, Jens; Wojtak, Radosław
We reanalyse observations of Type Ia supernovae (SNe) and Cepheids used in the local determination of the Hubble constant and find strong evidence that SN standardization in the calibration sample (galaxies with observed Cepheids) requires a steeper slope of the colour correction than in the cosmological sample (galaxies in the Hubble flow). The c…
Ultra-diffuse galaxies in the perseus cluster: comparing galaxy properties with globular cluster system richness
Forbes, Duncan A.; Romanowsky, Aaron J.; Brodie, Jean P. +6 more
It is clear that within the class of ultra-diffuse galaxies (UDGs), there is an extreme range in the richness of their associated globular cluster (GC) systems. Here, we report the structural properties of five UDGs in the Perseus cluster based on deep Subaru/Hyper Suprime-Cam imaging. Three appear GC-poor and two appear GC-rich. One of our sample…