Search Publications
Methanol along the path from envelope to protoplanetary disc
Walsh, Catherine; Harsono, Daniel; van Dishoeck, Ewine F. +2 more
Interstellar methanol is considered to be a parent species of larger, more complex organic molecules. A physicochemical simulation of infalling parcels of matter is performed for a low-mass star-forming system to trace the chemical evolution from cloud to disc. An axisymmetric 2D semi-analytic model generates the time-dependent density and velocit…
Kinematics and simulations of the stellar stream in the halo of the Umbrella Galaxy
Zibetti, S.; Martínez-Delgado, D.; Strader, J. +9 more
We study the dynamics of faint stellar substructures around the Umbrella Galaxy, NGC 4651, which hosts a dramatic system of streams and shells formed through the tidal disruption of a nucleated dwarf elliptical galaxy. We elucidate the basic characteristics of the system (colours, luminosities, stellar masses) using multiband Subaru/Suprime-Cam im…
The particle content of low-power radio galaxies in groups and clusters
Hardcastle, M. J.; Croston, J. H.
The synchrotron-radiating particles and magnetic fields in low-power radio galaxies (including most nearby cluster-centre sources), if at equipartition, can provide only a small fraction of the total internal energy density of the radio lobes or plumes, which is now well constrained via X-ray observations of their external environments. We conside…
On the connection between the intergalactic medium and galaxies: the H I-galaxy cross-correlation at z ≲ 1
Tejos, Nicolas; Bechtold, Jill; Davé, Romeel +9 more
We present a new optical spectroscopic survey of 1777 `star-forming' (`SF') and 366 `non-star-forming' (`non-SF') galaxies at redshifts z ∼ 0-1 (2143 in total), 22 AGN and 423 stars, observed by instruments such as the Deep Imaging Multi-Object Spectrograph, the Visible Multi-Object Spectrograph and the Gemini Multi-Object Spectrograph, in three f…
The Atacama Cosmology Telescope: dusty star-forming galaxies and active galactic nuclei in the Southern survey
Hilton, Matt; Bond, J. Richard; Crichton, Devin +28 more
We present a catalogue of 191 extragalactic sources detected by the Atacama Cosmology Telescope (ACT) at 148 and/or 218 GHz in the 2008 Southern survey. Flux densities span 14 -1700 mJy, and we use source spectral indices derived using ACT-only data to divide our sources into two subpopulations: 167 radio galaxies powered by central active galacti…
Starburst-AGN mixing - I. NGC 7130
Kewley, Lisa J.; Davies, Rebecca L.; Dopita, Michael A. +1 more
We present an integral field spectroscopic study of the luminous infrared galaxy NGC 7130, a known starburst-active galactic nucleus (AGN) composite galaxy. We employ standard emission-line ratio diagnostics and maps of velocity dispersion and velocity field to investigate how the dominant ionizing sources change as a function of radius. From the …
Constraining globular cluster formation through studies of young massive clusters - IV. Testing the fast rotating massive star scenario
Cabrera-Ziri, I.; Bastian, N.; Hollyhead, K.
One of the leading models for the formation of multiple stellar populations within globular clusters is the `fast rotating massive star' (FRMS) scenario, where the ejecta of rapidly rotating massive stars is mixed with primordial material left over from the star formation process, to form a second generation of stars within the decretion discs of …
Searching for large-scale structures around high-redshift radio galaxies with Herschel
Clements, D. L.; De Lucia, G.; Dannerbauer, H. +15 more
This paper presents the first results of a far-infrared search for protocluster-associated galaxy overdensities using the Spectral and Photometric Imaging REciever (SPIRE) instrument on-board the Herschel Space Observatory. Large (∼400 arcmin2) fields surrounding 26 powerful high-redshift radio galaxies (2.0 < z < 4.1; L500 M…
Filamentary star formation in NGC 1275
O'Connell, R. W.; Fabian, A. C.; Gallagher, J. S. +8 more
We examine the star formation in the outer halo of NGC 1275, the central galaxy in the Perseus cluster (Abell 426), using far-ultraviolet and optical images obtained with the Hubble Space Telescope. We have identified a population of very young, compact star clusters with typical ages of a few Myr. The star clusters are organized on multiple kilop…
Multiple density discontinuities in the merging galaxy cluster CIZA J2242.8+5301
Simionescu, A.; Croston, J. H.; Brüggen, M. +4 more
CIZA J2242.8+5301, a merging galaxy cluster at z = 0.19, hosts a double-relic system and a faint radio halo. Radio observations at frequencies ranging from a few MHz to several GHz have shown that the radio spectral index at the outer edge of the northern relic corresponds to a shock of Mach number 4.6_{-0.9}^{+1.3}, under the assumptions of diffu…