Search Publications
The tidal stream generated by the globular cluster NGC 3201
Miralda-Escudé, Jordi; Palau, Carles G.
We detect a tidal stream generated by the globular cluster NGC 3201 extending over ~140 deg on the sky, using the Gaia DR2 data, with the maximum-likelihood method we presented previously to study the M68 tidal stream. Most of the detected stream is the trailing one, which stretches in the southern Galactic hemisphere and passes within a close dis…
Radio pulsations from the γ-ray millisecond pulsar PSR J2039-5617
Belfiore, A.; Venter, C.; Possenti, A. +9 more
The predicted nature of the candidate redback pulsar 3FGL J2039.6-5618 was recently confirmed by the discovery of γ-ray millisecond pulsations (Clark et al., hereafter Paper I), which identify this γ-ray source as PSR J2039-5617. We observed this object with the Parkes radio telescope in 2016 and 2019. We detect radio pulsations at 1.4 and 3.1 GHz…
A search for satellite galaxies of nearby star-forming galaxies with resolved stars in LBT-SONG
Kochanek, Christopher S.; Sand, David J.; Peter, Annika H. G. +2 more
We present results from a resolved stellar population search for dwarf satellite galaxies of six nearby (D < 5 Mpc), sub-Milky Way mass hosts using deep (m ~ 27 mag) optical imaging from the Large Binocular Telescope. We perform image simulations to quantify our detection efficiency for dwarfs over a large range in luminosity and size, and deve…
Exploring the dust content of galactic haloes with Herschel III. NGC 891
Veilleux, S.; Martin, Crystal L.; Gordon, K. D. +6 more
We present deep far-infrared observations of the nearby edge-on galaxy NGC 891 obtained with the Herschel Space Observatory and the Spitzer Space Telescope. The maps confirm the detection of thermal emission from the inner circumgalactic medium (halo) and spatially resolve a dusty superbubble and a dust spur (filament). The dust temperature of the…
Low-mass compact elliptical galaxies: spatially resolved stellar populations and kinematics with the Keck Cosmic Web Imager
Forbes, Duncan A.; Romanowsky, Aaron J.; Brodie, Jean P. +4 more
We present spatially resolved two-dimensional maps and radial trends of the stellar populations and kinematics for a sample of six compact elliptical galaxies (cE) using spectroscopy from the Keck Cosmic Web Imager (KCWI). We recover their star formation histories, finding that all except one of our cEs are old and metal rich, with both age and me…
3D mapping of the Crab Nebula with SITELLE - I. Deconvolution and kinematic reconstruction
Milisavljevic, D.; Drissen, L.; Martin, T.
We present a hyperspectral cube of the Crab Nebula obtained with the imaging Fourier transform spectrometer SITELLE on the Canada-France-Hawaii telescope. We describe our techniques used to deconvolve the 310 000 individual spectra ($R = 9\, 600$) containing Hα, [N II] λλ6548, 6583, and [S II] λλ6716, 6731 emission lines and create a detailed 3D r…
The GALAH survey: accreted stars also inhabit the Spite plateau
Lewis, Geraint F.; Ting, Yuan-Sen; Casey, Andrew R. +23 more
The European Space Agency (ESA) Gaia mission has enabled the remarkable discovery that a large fraction of the stars near the solar neighbourhood are debris from a single in-falling system, the so-called Gaia-Sausage-Enceladus (GSE). This discovery provides astronomers for the first time with a large cohort of easily observable, unevolved stars th…
A high occurrence of nuclear star clusters in faint Coma galaxies, and the roles of mass and environment
Chies-Santos, Ana L.; Blakeslee, John P.; Sánchez-Janssen, Rubén +2 more
We use deep high-resolution Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) imaging of two fields in the core of the Coma Cluster to investigate the occurrence of nuclear star clusters (NSCs) in quiescent dwarf galaxies as faint as MI = -10 mag. We employ a hierarchical Bayesian logistic regression framework to model the …
Characterizing the Gaia radial velocity sample selection function in its native photometry
Rix, Hans-Walter; Bailer-Jones, Coryn A. L.; Rybizki, Jan +2 more
The Gaia Data Release 2 (DR2) radial velocity sample (GDR2RVS), which provides six-dimensional phase-space information on 7.2 million stars, is of great value for inferring properties of the Milky Way. Yet a quantitative and accurate modelling of this sample is hindered without knowledge and inclusion of a well-characterized selection f…
Carbon dust in the evolved born-again planetary nebulae A 30 and A 78
Estrada-Dorado, S.; Guerrero, M. A.; Toalá, J. A. +6 more
We present an infrared (IR) characterization of the born-again planetary nebulae (PNe) A 30 and A 78 using IR images and spectra. We demonstrate that the carbon-rich dust in A 30 and A 78 is spatially coincident with the H-poor ejecta and coexists with hot X-ray-emitting gas up to distances of 50 arcsec from the central stars of PNe (CSPNe). Dust …