Search Publications
The orbital anisotropy profiles of nearby globular clusters from Gaia Data Release 2
Bovy, Jo; Webb, Jeremy J.; Jindal, Abhinav
Gaia Data Release 2 provides a wealth of data to study the internal structure of nearby globular clusters (GCs). We use this data to investigate the internal kinematics of 10 nearby GCs, with a particular focus on their poorly studied outer regions. We apply a strict set of selection criteria to remove contaminating sources and create pure cluster…
Detecting dark matter cores in galaxy clusters with strong lensing
Andrade, Kevin E.; Minor, Quinn; Kaplinghat, Manoj +1 more
We test the ability of strong lensing data to constrain the size of a central core in the dark matter haloes of galaxy clusters, using Abell 611 as a prototype. Using simulated data, we show that modelling a cluster halo with ellipticity in the gravitational potential can bias the inferred mass and concentration, which may bias the inferred centra…
The ASKAP EMU Early Science Project: radio continuum survey of the Small Magellanic Cloud
Haberl, F.; Umana, G.; Filipović, M. D. +53 more
We present two new radio continuum images from the Australian Square Kilometre Array Pathfinder (ASKAP) survey in the direction of the Small Magellanic Cloud (SMC). These images are part of the Evolutionary Map of the Universe (EMU) Early Science Project (ESP) survey of the Small and Large Magellanic Clouds. The two new source lists produced from …
Globular clusters formed within dark haloes I: present-day abundance, distribution, and kinematics
Peng, Eric W.; Sales, Laura V.; Creasey, Peter +1 more
We explore a scenario where metal-poor globular clusters (GCs) form at the centres of their own dark matter haloes in the early Universe before reionization. This hypothesis leads to predictions about the abundance, distribution, and kinematics of GCs today that we explore using cosmological N-body simulations and analytical modelling. We find tha…
From kpcs to the central parsec of NGC 1097: feeding star formation and a black hole at the same time
Bruzual, Gustavo; Burkert, Andreas; Prieto, M. Almudena +3 more
A panchromatic view of the star-forming ring and feeding process in the central kpc of the galaxy NGC 1097 is presented. The assembled IR to UV images at ∼10 pc resolution allow us to characterize the population of circa 250 clusters in the ring and disentangle the network of filaments of dust and gas that enshroud and feed them. The ring is a pla…
Three-dimensional dust mapping of 12 supernovae remnants in the Galactic anticentre
Zijlstra, A.; Jiang, B. W.; Chen, B. Q. +1 more
We present three-dimensional (3D) dust mapping of 12 supernova remnants (SNRs) in the Galactic anticentre (Galactic longitude l between 150° and 210°) based on a recent 3D interstellar extinction map. The dust distribution of the regions, which cover the full extents in the radio continuum for the individual SNRs, is discussed. Four SNRs show sign…
Statistical detection of a tidal stream associated with the globular cluster M68 using Gaia data
Miralda-Escudé, Jordi; Palau, Carles G.
A method to search for tidal streams and to fit their orbits based on maximum likelihood is presented and applied to the Gaia data. Tests of the method are performed showing how a simulated stream produced by tidal stripping of a star cluster is recovered when added to a simulation of the Gaia catalogue. The method can be applied to search for str…
Spherical models of star clusters with potential escapers
Varri, Anna Lisa; Heggie, Douglas C.; Gieles, Mark +2 more
An increasing number of observations of the outer regions of globular clusters (GCs) have shown a flattening of the velocity dispersion profile and an extended surface density profile. Formation scenarios of GCs can lead to different explanations of these peculiarities, therefore the dynamics of stars in the outskirts of GCs are an important tool …
K2 Ultracool Dwarfs Survey - V. High superflare rates on rapidly rotating late-M dwarfs
Mullan, D. J.; Burgasser, A. J.; Stassun, K. G. +5 more
We observed strong superflares (defined as flares with energy in excess of 1033 erg) on three late-M dwarfs: 2MASS J08315742+2042213 (hereafter 2M0831+2042; M7 V), 2MASS J08371832+2050349 (hereafter 2M0837+2050; M8 V), and 2MASS J08312608+2244586 (hereafter 2M0831+2244; M9 V). 2M0831+2042 and 2M0837+2050 are members of the young (∼700 M…
Age gradients throughout the Galaxy with long-period variables
Evans, N. W.; Belokurov, V.; Grady, J.
We assemble the largest sample of oxygen-rich (O-rich) Miras and associated long-period variables (LPVs) to date and highlight their importance for age dating the components of the Galaxy. Using data from the Catalina Surveys and the All Sky Automated Survey for Supernovae, we extract a clean sample of ∼2200 O-rich LPVs, stretching from the Galact…