Search Publications
The most extreme ultraluminous X-ray sources: evidence for intermediate-mass black holes?
Sutton, Andrew D.; Roberts, Timothy P.; Walton, Dominic J. +2 more
We present the results from an X-ray and optical study of a new sample of eight extreme luminosity ultraluminous X-ray source (ULX) candidates, which were selected as the brightest ULXs (with LX > 5 × 1040 erg s-1) located within 100 Mpc identified in a cross-correlation of the 2XMM-DR1 and RC3 catalogues. These…
Diffuse Lyα haloes around Lyα emitters at z=3: do dark matter distributions determine the Lyα spatial extents?
Ouchi, M.; Yamada, T.; Matsuda, Y. +7 more
Using stacks of Lyα images of 2128 Lyα emitters (LAEs) and 24 proto-cluster UV-selected galaxies (LBGs) at z = 3.1, we examine the surface brightness profiles of Lyα haloes around high-z galaxies as a function of environment and UV luminosity. We find that the slopes of the Lyα radial profiles become flatter as the Mpc-scale LAE surface density in…
Mapping the cold dust temperatures and masses of nearby KINGFISH galaxies with Herschel
Roussel, H.; Armus, L.; Weiss, A. +18 more
Taking advantage of the unprecedented combination of sensitivity and angular resolution afforded by the Herschel Space Observatory at far-infrared and submillimetre wavelengths, we aim to characterize the physical properties of cold dust within nearby galaxies, as well as the associated uncertainties, namely the robustness of the parameters we der…
On the determination of the spin of the black hole in Cyg X-1 from X-ray reflection spectra
Fabian, A. C.; Miller, J. M.; Reynolds, C. S. +9 more
The spin of Cygnus X-1 is measured by fitting reflection models to Suzaku data covering the energy band 0.9-400 keV. The inner radius of the accretion disc is found to lie within 2 gravitational radii (rg=GM/c2), and a value of ? is obtained for the dimensionless black hole spin. This agrees with recent measurements using the…
Homogeneous studies of transiting extrasolar planets - V. New results for 38 planets
Southworth, John
I measure the physical properties of 38 transiting extrasolar planetary systems, bringing the total number studied within the Homogeneous Studies project to 82. Transit light curves are modelled using the jktebop code, with careful attention paid to limb darkening, orbital eccentricity and contaminating light. The physical properties of each syste…
1H 0707-495 in 2011: an X-ray source within a gravitational radius of the event horizon
Schartel, N.; Santos-Lleó, M.; Fabian, A. C. +8 more
The narrow-line Seyfert 1 Galaxy 1H 0707-495 went into a low state from 2010 December to 2011 February, discovered by a monitoring campaign using the X-Ray Telescope on the Swift satellite. We triggered a 100 ks XMM-Newton observation of the source in 2011 January, revealing the source to have dropped by a factor of 10 in the soft band, below 1 ke…
99 Herculis: host to a circumbinary polar-ring debris disc
Duchêne, G.; Wyatt, M. C.; Matthews, B. C. +6 more
We present resolved Herschel images of a circumbinary debris disc in the 99 Herculis system. The primary is a late F-type star. The binary orbit is well characterized and we conclude that the disc is misaligned with the binary plane. Two different models can explain the observed structure. The first model is a ring of polar orbits that move in a p…
The SLUGGS survey: calcium triplet-based spectroscopic metallicities for over 900 globular clusters
Spitler, Lee R.; Forbes, Duncan A.; Romanowsky, Aaron J. +6 more
Although the colour distribution of globular clusters in massive galaxies is well known to be bimodal, the spectroscopic metallicity distribution has been measured in only a few galaxies. After redefining the calcium triplet index-metallicity relation, we use our relation to derive the metallicity of 903 globular clusters in 11 early-type galaxies…
A Suzaku survey of Fe K lines in Seyfert 1 active galactic nuclei
Porquet, D.; Reeves, J. N.; Braito, V. +3 more
We construct full broad-band models in an analysis of Suzaku observations of nearby Seyfert 1 active galactic nuclei (AGN) (z ≤ 0.2) with exposures >50 ks and with greater than 30 000 counts in order to study their iron line profiles. This results in a sample of 46 objects and 84 observations. After a full modelling of the broad-band Suzaku and…
A remarkably high fraction of strong Lyα emitters amongst luminous redshift 6.0 < z < 6.5 Lyman-break galaxies in the UKIDSS Ultra-Deep Survey
McLure, R. J.; Dunlop, J. S.; Cirasuolo, M. +8 more
We present spectroscopic confirmation of 10 highly luminous (L≥ 2L★) Lyα emitters (LAEs) in the redshift range 6.01 < z < 6.49 (nine galaxies and one active galactic nucleus), initially drawn from a sample of 14 zphot≥ 6 Lyman-break galaxies (LBGs) selected from an area of 0.25 deg2 within the UK Infrared Dee…