Search Publications
A combined optical and X-ray study of unobscured type 1 active galactic nuclei - I. Optical spectra and spectral energy distribution modelling
Done, Chris; Ward, Martin; Jin, Chichuan +1 more
We present modelling and interpretation of the continuum and emission lines for a sample of 51 unobscured type 1 active galactic nuclei (AGNs). All of these AGNs have high-quality spectra from both XMM-Newton and the Sloan Digital Sky Survey. We extend the wavelength coverage where possible by adding simultaneous ultraviolet data from the OM onboa…
The DEEP3 Galaxy Redshift Survey: the impact of environment on the size evolution of massive early-type galaxies at intermediate redshift
Weiner, Benjamin J.; Davis, Marc; Faber, S. M. +10 more
Using data drawn from the DEEP2 and DEEP3 Galaxy Redshift Surveys, we investigate the relationship between the environment and the structure of galaxies residing on the red sequence at intermediate redshift. Within the massive (10 < log10(M★/h-2 M⊙) < 11) early-type population at 0.4 < z < 1.…
GALAPAGOS: from pixels to parameters
Barden, Marco; Peng, Chien Y.; McIntosh, Daniel H. +2 more
To automate source detection, two-dimensional light profile Sérsic modelling and catalogue compilation in large survey applications, we introduce a new code Galaxy Analysis over Large Areas: Parameter Assessment by GALFITting Objects from SEXTRACTOR (GALAPAGOS). Based on a single set-up, GALAPAGOS can process a complete set of survey images. It de…
The nature of the Compton-thick X-ray reprocessor in NGC 4945
Yaqoob, Tahir
We present an exhaustive methodology for fitting Compton-thick X-ray reprocessor models to obscured active galactic nuclei (AGNs) and for interpreting the results. We focus on the MYTORUS model but also include some analysis from other models. The models are applied specifically to Suzaku, BeppoSAX and Swift Burst Alert Telescope spectra of the Se…
The properties of the star-forming interstellar medium at z = 0.84-2.23 from HiZELS: mapping the internal dynamics and metallicity gradients in high-redshift disc galaxies
Smail, Ian; Swinbank, A. M.; Geach, J. E. +5 more
We present adaptive optics assisted, spatially resolved spectroscopy of a sample of nine Hα-selected galaxies at z = 0.84-2.23 drawn from the HiZELS narrow-band survey. These galaxies have star formation rates of 1-27 M⊙ yr-1 and are therefore representative of the typical high-redshift star-forming population. Our ∼kpc-scale…
A critical analysis of the ultraviolet continuum slopes (β) of high-redshift galaxies: no evidence (yet) for extreme stellar populations at z > 6
McLure, R. J.; Dunlop, J. S.; Cirasuolo, M. +4 more
Following the discovery of the first significant samples of galaxies at z > 6.5 with Wide Field Camera 3/Infra-Red (WFC3/IR) on board Hubble Space Telescope (HST), it has been claimed that the faintest high-redshift galaxies display extremely blue ultraviolet (UV) continuum slopes, with a UV power-law index β≃-3 (where fλ∝λβ
The XMM Cluster Survey: optical analysis methodology and the first data release
Hilton, Matt; Stanford, S. A.; Stott, John P. +36 more
The XMM Cluster Survey (XCS) is a serendipitous search for galaxy clusters using all publicly available data in the XMM-Newton Science Archive. Its main aims are to measure cosmological parameters and trace the evolution of X-ray scaling relations. In this paper we present the first data release from the XMM Cluster Survey (XCS-DR1). This consists…
Relativistic iron K X-ray reverberation in NGC 4151
Fabian, A. C.; Reynolds, C. S.; Cackett, E. M. +1 more
Recent X-ray observations have enabled the study of reverberation delays in active galactic nuclei (AGN) for the first time. All the detections so far are in sources with a strong soft excess, and the measured delay is between the hard (1-3 keV) direct continuum and the soft excess (0.5-1 keV), interpreted as the reflection continuum smeared by re…
Optimal estimation retrievals of the atmospheric structure and composition of HD 189733b from secondary eclipse spectroscopy
Fletcher, L. N.; Lee, J. -M.; Irwin, P. G. J.
Recent spectroscopic observations of transiting hot Jupiters have permitted the derivation of the thermal structure and molecular abundances of H2O, CO2, CO and CH4 in these extreme atmospheres. Here, for the first time, we apply the technique of optimal estimation to determine the thermal structure and composition…
The morphologies of massive galaxies at 1 < z < 3 in the CANDELS-UDS field: compact bulges, and the rise and fall of massive discs
Ferguson, H. C.; McLure, R. J.; Dunlop, J. S. +16 more
We have used high-resolution, Hubble Space Telescope, near-infrared imaging to conduct a detailed analysis of the morphological properties of the most massive galaxies at high redshift, modelling the WFC3/IR H160-band images of the ≃200 galaxies in the CANDELS-UDS field with photometric redshifts 1 < z < 3, and stellar masses M