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Gurkan G.,University of Hertfordshire | Hardcastle M.J.,University of Hertfordshire | Jarvis M.J.,Keble Road | Jarvis M.J.,University of the Western Cape
Monthly Notices of the Royal Astronomical Society | Year: 2014

We present an analysis of four complete samples of radio-loud active galactic nucleus (AGN; 3CRR, 2Jy, 6CE and 7CE) using near- and mid-IR data taken by theWide-field Infrared Survey Explorer (WISE). The combined sample consists of 79 quasars and 273 radio galaxies, and covers a redshift range 0.003


Jarvis M.J.,Keble Road | Jarvis M.J.,University of Hertfordshire | Jarvis M.J.,University of the Western Cape | Bonfield D.G.,University of Hertfordshire | And 27 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2013

In this paper, we describe the first data release of the Visible and Infrared Survey Telescope for Astronomy (VISTA) Deep Extragalactic Observations (VIDEO) survey. VIDEO is a~12 deg2 survey in the near-infrared Z, Y, J, Hand Ks bands, specifically designed to enable the evolution of galaxies and large structures to be traced as a function of both epoch and environment from the present day out to z = 4, and active galactic nuclei (AGNs) and the most massive galaxies up to and into the epoch of reionization. With its depth and area, VIDEO will be able to fully explore the period in the Universe where AGN and starburst activity were at their peak and the first galaxy clusters were beginning to virialize. VIDEO therefore offers a unique data set with which to investigate the interplay between AGN, starbursts and environment, and the role of feedback at a time when it was potentially most crucial. We provide data over the VIDEO-XMM3 tile, which also covers the Canada-France-Hawaii Telescope Legacy Survey Deep-1 field (CFHTLS-D1). The released VIDEO data reach a 5σ AB-magnitude depth of Z = 25.7, Y = 24.5, J = 24.4, H = 24.1 and Ks = 23.8 in 2 arcsec diameter apertures (the full depth of Y = 24.6 will be reached within the full integration time in future releases). The data are compared to previous surveys over this field and we find good astrometric agreement with the Two Micron All Sky Survey, and source counts in agreement with the recently released UltraVISTA survey data. The addition of the VIDEO data to the CFHTLS-D1 optical data increases the accuracy of photometric redshifts and significantly reduces the fraction of catastrophic outliers over the redshift range 0 < z < 1 from 5.8 to 3.1 per cent in the absence of an i-band luminosity prior. However, we expect that the main improvement in photometric redshifts will come in the redshift range 1 < z < 4 due to the sensitivity to the Balmer and 4000 Å breaks provided by the near-infrared VISTA filters. All images and catalogues presented in this paper are publicly available through ESO's phase 3 archive and the VISTA Science Archive. © 2012 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.


Banerji M.,University College London | Jouvel S.,University College London | Lin H.,Fermi National Accelerator Laboratory | McMahon R.G.,University of Cambridge | And 88 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2014

We present the combination of optical data from the Science Verification phase of the Dark Energy Survey (DES) with near-infrared (NIR) data from the European Southern Observatory VISTA Hemisphere Survey (VHS). The deep optical detections from DES are used to extract fluxes and associated errors from the shallower VHS data. Joint seven-band (grizYJK) photometric catalogues are produced in a single 3 sq-deg dedicated camera field centred at 02h26m-04d36m where the availability of ancillary multiwavelength photometry and spectroscopy allows us to test the data quality. Dual photometry increases the number of DES galaxies with measured VHS fluxes by a factor of ~4.5 relative to a simple catalogue level matching and results in a ~1.5 mag increase in the 80 per cent completeness limit of the NIR data. Almost 70 per cent of DES sources have useful NIR flux measurements in this initial catalogue. Photometric redshifts are estimated for a subset of galaxies with spectroscopic redshifts and initial results, although currently limited by small number statistics, indicate that the VHS data can help reduce the photometric redshift scatter at both z < 0.5 and z > 1. We present example DES+VHS colour selection criteria for high-redshift luminous red galaxies (LRGs) at z ~ 0.7 as well as luminous quasars. Using spectroscopic observations in this field we show that the additional VHS fluxes enable a cleaner selection of both populations with <10 per cent contamination from galactic stars in the case of spectroscopically confirmed quasars and <0.5 per cent contamination from galactic stars in the case of spectroscopically confirmed LRGs. The combined DES+VHS data set, which will eventually cover almost 5000 sq-deg, will therefore enable a range of new science and be ideally suited for target selection for future wide-field spectroscopic surveys. © 2014 The Authors.


Blanchon G.,National Institute of Nuclear Physics, Italy | Blanchon G.,University of Pisa | Blanchon G.,CEA DAM Ile-de-France | Bonaccorso A.,National Institute of Nuclear Physics, Italy | And 2 more authors.
Journal of Physics: Conference Series | Year: 2010

The level ordering in the unbound nuclei 10Li and 13Be is established on a firm basis using a time dependent projectile fragmentation model, comparing to experimental data and using structure inputs obtained from a semi-phenomenological core-vibration coupling model of two-neutron halo nuclei. The information on the shell ordering corresponds to the understanding of the neutron-core interaction. This is a building block of any three body model of borromean nuclei. As a consistency test we show that the energy spectra of some Beryllium isotopes obtained by using pp-RPA predict the same shell ordering as extracted from the reaction model vs. data analysis and that the well known structure of 11Li is reproduced. © 2010 IOP Publishing Ltd.

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