Search Publications
Resolving local and global kinematic signatures of satellite mergers with billion particle simulations
Laporte, Chervin F. P.; Johnston, Kathryn V.; Hunt, Jason A. S. +3 more
In this work, we present two new ~109 particle self-consistent simulations of the merger of a Sagittarius-like dwarf galaxy with a Milky Way (MW)-like disc galaxy. One model is a violent merger creating a thick disc, and a Gaia-Enceladus/Sausage-like remnant. The other is a highly stable disc which we use to illustrate how the improved …
On the multiwavelength variability of Mrk 110: two components acting at different time-scales
McHardy, I.; Breedt, E.; Peterson, B. M. +17 more
We present the first intensive continuum reverberation mapping study of the high accretion-rate Seyfert galaxy Mrk 110. The source was monitored almost daily for more than 200 d with the Swift X-ray and ultraviolet (UV)/optical telescopes, supported by ground-based observations from Las Cumbres Observatory, the Liverpool Telescope, and the Zowada …
A tale of two mergers: constraints on kilonova detection in two short GRBs at z ∼ 0.5
Troja, E.; Wollaeger, R. T.; Cenko, S. B. +15 more
We present a detailed multiwavelength analysis of two short gamma-ray bursts (sGRBs) detected by the Neil Gehrels Swift Observatory: GRB 160624A at $z$ = 0.483 and GRB 200522A at $z$ = 0.554. These sGRBs demonstrate very different properties in their observed emission and environment. GRB 160624A is associated with a late-type galaxy with an old s…
The search for failed supernovae with the Large Binocular Telescope: N6946-BH1, still no star
Kochanek, C. S.; Stanek, K. Z.; Dai, X. +2 more
We present new Large Binocular Telescope, Hubble Space Telescope, and Spitzer Space Telescope data for the failed supernova candidate N6946-BH1. We also report an unsuccessful attempt to detect the candidate with Chandra. The ~300 000 $\, \mathrm{L}_\odot$ red supergiant progenitor underwent an outburst in 2009 and has since disappeared in the opt…
An unusually low density ultra-short period super-Earth and three mini-Neptunes around the old star TOI-561
Scandariato, G.; Pagano, I.; Winn, J. N. +38 more
Based on HARPS-N radial velocities (RVs) and TESS photometry, we present a full characterization of the planetary system orbiting the late G dwarf TOI-561. After the identification of three transiting candidates by TESS, we discovered two additional external planets from RV analysis. RVs cannot confirm the outer TESS transiting candidate, which wo…
Probing the nature of dark matter with accreted globular cluster streams
Malhan, Khyati; Valluri, Monica; Freese, Katherine
The steepness of the central density profiles of dark matter (DM) in low-mass galaxy haloes (e.g. dwarf galaxies) is a powerful probe of the nature of DM. We propose a novel scheme to probe the inner profiles of galaxy subhaloes using stellar streams. We show that the present-day morphological and dynamical properties of accreted globular cluster …
A circular polarization survey for radio stars with the Australian SKA Pathfinder
Kaplan, David L.; Lenc, Emil; Pritchard, Joshua +14 more
We present results from a circular polarization survey for radio stars in the Rapid ASKAP Continuum Survey (RACS). RACS is a survey of the entire sky south of δ = +41○ being conducted with the Australian Square Kilometre Array Pathfinder telescope (ASKAP) over a 288 MHz wide band centred on 887.5 MHz. The data we analyse include Stokes …
Metal-enriched halo gas across galaxy overdensities over the last 10 billion years
Tripp, Todd M.; Prochaska, J. Xavier; Tejos, Nicolas +15 more
We present a study of metal-enriched halo gas traced by Mg II and C IV absorption at z < 2 in the MUSE Analysis of Gas around Galaxies survey and the Quasar Sightline and Galaxy Evolution survey. Using these large and complete galaxy surveys in quasar fields, we study the dependence of the metal distribution on galaxy properties and overdensiti…
The cumulative star formation histories of dwarf galaxies with TNG50. I: environment-driven diversity and connection to quenching
Vogelsberger, Mark; Pillepich, Annalisa; Springel, Volker +5 more
We present the cumulative star formation histories (SFHs) of >15 000 dwarf galaxies ($M_{\rm *}=10^{7-10}\, {\rm M}_{\odot }$) simulated with the TNG50 run of the IllustrisTNG suite across a vast range of environments. The key factors that determine the dwarfs' SFHs are their central/satellite status and stellar mass, with centrals and more mas…
TOI-257b (HD 19916b): a warm sub-saturn orbiting an evolved F-type star
Henning, Thomas; Vanderburg, Andrew; Chaplin, William J. +91 more
We report the discovery of a warm sub-Saturn, TOI-257b (HD 19916b), based on data from NASA's Transiting Exoplanet Survey Satellite (TESS). The transit signal was detected by TESS and confirmed to be of planetary origin based on radial velocity observations. An analysis of the TESS photometry, the MINERVA-Australis, FEROS, and HARPS radial velocit…