Search Publications
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…
Feeding and feedback in the inner kiloparsec of the active galaxy NGC 2110
Robinson, Andrew; Schnorr-Müller, Allan; Storchi-Bergmann, Thaisa +4 more
We present two-dimensional gaseous kinematics of the inner 1.1 × 1.6 kpc2 of the Seyfert 2 galaxy NGC 2110, from optical spectra (5600-7000 Å) obtained with the Gemini Multi Object Spectrograph integral field spectrograph on the Gemini South telescope at a spatial resolution of ≈100 pc. Gas emission is observed over the whole field of v…
The many sides of RCW 86: a Type Ia supernova remnant evolving in its progenitor's wind bubble
Vink, Jacco; Bamba, Aya; Chiotellis, Alexandros +1 more
We present the results of a detailed investigation of the Galactic supernova remnant RCW 86 using the XMM-Newton X-ray telescope. RCW 86 is the probable remnant of SN 185 A.D., a supernova that likely exploded inside a wind-blown cavity. We use the XMM-Newton Reflection Grating Spectrometer to derive precise temperatures and ionization ages of the…