David G. Bonfield

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We present the Spitzer Extragalactic Representative Volume Survey (SERVS), an 18 deg 2 medium-deep survey at 3.6 and 4.5 µm with the post-cryogenic Spitzer Space Telescope to ≈ 2 µJy (AB = 23.1) depth of five highly observed astronomical fields (ELAIS-N1, ELAIS-S1, Lockman Hole, Chandra Deep Field South and XMM-LSS). SERVS is designed to enable the study of(More)
Fibre Multi-Object Spectrograph (FMOS) is the first near-infrared instrument with a wide field of view capable of acquiring spectra simultaneously from up to 400 objects. It has been developed as a common-use instrument for the F/2 prime-focus of the Subaru Telescope. The field coverage of 30 diameter is achieved using a new 3-element corrector optimized in(More)
We present a technique to identify optical counterparts of 250-μm-selected sources from the Herschel–ATLAS survey. Of the 6621 250 μm > 32-mJy sources in our science demonstration Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.
We present a comparison between Gaussian processes (GPs) and artificial neural networks (ANNs) as methods for determining photometric redshifts for galaxies, given training set data. In particular, we compare their degradation in performance as the training set size is degraded in ways which might be caused by the observational limitations of spectroscopy.(More)
The UK FMOS spectrograph forms part of Subaru's FMOS multi-object infrared spectroscopy facility. The spectrograph was shipped to Hilo in component form in August of 2007. We describe the integration sequence for the spectrograph, the results of cooldown tests using a new chiller unit fitted to the spectrograph at the telescope, and alignment tests of the(More)
In this paper we investigate the performance of the likelihood ratio method as a tool for identifying optical and infrared counterparts to proposed radio continuum surveys with SKA precursor and pathfinder telescopes. We present a comparison of the in-frared counterparts identified by the likelihood ratio in the VISTA Deep Extragalactic Observations (VIDEO)(More)
Gravitational lensing is a powerful astrophysical and cosmological probe and is particularly valuable at submillimeter wavelengths for the study of the statistical and individual properties of dusty star-forming galaxies. However, the identification of gravitational lenses is often time-intensive, involving the sifting of large volumes of imaging or(More)
We have measured the clustering properties of low-redshift (z < 0.3) sub-mm galaxies detected at 250 µm in the Herschel-ATLAS Science Demonstration Phase (SDP) field. We selected a sample for which we have high-quality spectroscopic redshifts, obtained from reliably matching the 250-µm sources to a complete (for r < 19.4) sample of galaxies from the GAMA(More)
There is an ongoing debate concerning the driver of nuclear activity in galaxies, with AGN either being triggered by major or minor galactic mergers or, alternatively, through secular processes like cooling gas accretion and/or formation of bars. We investigate the close environment of active galaxies selected in the X-ray, the radio, and the mid-IR. We(More)