Search Publications
A search for stellar structures around nine outer halo globular clusters in the Milky Way
Mackey, Dougal; Da Costa, Gary S.; Zhang, Shumeng
We use deep imaging from the Dark Energy Camera to explore the peripheral regions of nine globular clusters in the outer halo of the Milky Way. Apart from Whiting 1 and NGC 7492, which are projected against the Sagittarius stream, we see no evidence for adjacent stellar populations to indicate any of these clusters is associated with coherent tida…
Scaling relations for globular cluster systems in early-type galaxies - II. Is there an environmental dependence?
Bassino, Lilia P.; Caso, Juan P.; Ennis, Ana I. +1 more
The current properties of globular cluster systems (GCSs) are the result of the evolution experienced by their host galaxies, which shape the richness of the GCS as well as its spatial distribution, among other features. We carry out an analysis of the projected radial distribution of globular clusters for a sample of almost 30 early-type galaxies…
White dwarfs identified in LAMOST Data Release 5
Liu, Jifeng; Bai, Yu; Zhang, Huawei +5 more
In this paper, we report white dwarfs (WD) identified in the 5th Data Release of the Large Area Multi-Object fibre Spectroscopic Telescope (LAMOST), including spectral types of DA, DB, DC, DZ, and so on. There are 2625 DA spectra of 2281 DA stars, 182 DB spectra of 166 DB stars, 62 DC spectra of 58 DC stars, 36 DZ spectra of 33 DZ stars…
Rapidly oscillating TESS A-F main-sequence stars: are the roAp stars a distinct class?
Balona, L. A.
From sector 1-44 TESS observations, 19 new rapidly oscillating Ap (roAp) stars, 103 ostensibly non-peculiar stars with roAp-like frequencies, and 617 δ Scuti stars with independent frequencies typical of roAp stars were found. Examination of all chemically peculiar stars observed by TESS resulted in the discovery of 199 Ap stars that pulsate as δ …
Ram pressure candidates in UNIONS
Chambers, Kenneth C.; Wainscoat, Richard J.; Oguri, Masamune +17 more
We present a search for disturbed, candidate ram pressure stripping galaxies across more than 50 spectroscopically selected SDSS groups and clusters. 48 ram pressure candidates are visually identified in these systems using high-quality UNIONS imaging from the Canada-France-Hawaii Telescope, covering ${\sim }6200\, \mathrm{deg^2}$ and ${\sim }2800…
Constraints on the Galactic Centre environment from Gaia hyper-velocity stars
Rossi, E. M.; Marchetti, T.; Evans, F. A.
Following a dynamical encounter with Sgr A*, binaries in the Galactic Centre (GC) can be tidally separated and one member star ejected as a hyper-velocity star (HVS) with a velocity beyond the escape speed of the Milky Way. As GC-born objects located in more observationally accessible regions of the sky, HVSs offer insight into the stellar populat…
The structure of accreted stellar streams
Bovy, Jo; Qian, Yansong; Arshad, Yumna
Many of the Milky Way's globular clusters are likely accreted from satellite galaxies that have long since merged with the Milky Way. When these globular clusters are susceptible to tidal disruption, this process likely starts already inside the parent satellite leading to an early stellar stream within the satellite. When the parent satellite mer…
Estimating the local dark matter density in a non-axisymmetric wobbling disc
Sivertsson, S.; Read, J. I.; Silverwood, H. +6 more
The density of dark matter near the Sun, ρDM, ⊙, is important for experiments hunting for dark matter particles in the laboratory, and for constraining the local shape of the Milky Way's dark matter halo. Estimates to date have typically assumed that the Milky Way's stellar disc is axisymmetric and in a steady-state. Yet the Milky Way d…
The Pristine survey - XVII. The C-19 stream is dynamically hot and more extended than previously thought
Fouesneau, Morgan; Sestito, Federico; Navarro, Julio F. +22 more
The C-19 stream is the most metal-poor stellar system ever discovered, with a mean metallicity [Fe/H] = -3.38 ± 0.06. Its low metallicity dispersion (σ[Fe/H] < 0.18 at the 95 per cent confidence level) and variations in sodium abundances strongly suggest a globular cluster origin. In this work, we use Very Large Telescope (VLT)/UV-Vi…
A double-peaked Lyman-α emitter with a stronger blue peak multiply imaged by the galaxy cluster RXC J0018.5+1626
Charlot, Stéphane; Bradač, Maruša; Strait, Victoria +10 more
We report the discovery of a double-peaked Lyman-α (Ly α) emitter (LAE) at z = 3.2177 ± 0.0001 in VLT/MUSE data. The galaxy is strongly lensed by the galaxy cluster RXC J0018.5+1626 recently observed in the RELICS survey, and the double-peaked Ly α emission is clearly detected in the two counter images in the MUSE field of view. We measure a relat…