Search Publications
Near-infrared integral field spectroscopy of the Homunculus nebula around η Carinae using Gemini/CIRPASS
Sharp, R. G.; Damineli, A.; Groh, J. H. +2 more
This work presents the first integral field spectroscopy of the Homunculus nebula around η Carinae in the near-infrared spectral region (J band). We confirmed the presence of a hole on the polar region of each lobe, as indicated by previous near-IR long-slit spectra and mid-IR images. The holes can be described as a cylinder of height (i.e. the th…
The environments of SLACS gravitational lenses
Auger, M. W.
We report on an investigation of the environments of the Sloan Lens ACS Survey (SLACS) sample of gravitational lenses. The local and global environments of the lenses are characterized using Sloan Digital Sky Survey (SDSS) photometry and, when available, spectroscopy. We find that the lens systems that are best modelled with steeper than isotherma…
The nature of the intranight variability of radio-quiet quasars
Siemiginowska, A.; Czerny, B.; Gupta, A. C. +1 more
We select a sample of 10 radio-quiet quasars with confirmed intranight optical variability and with available X-ray data. We compare the variability properties and the broad-band spectral constraints to the predictions of intranight variability by three models: (i) irradiation of an accretion disc by a variable X-ray flux, (ii) an accretion disc i…
The mid-infrared [SIV]/[NeII] versus [NeIII]/[NeII] correlation
Groves, Brent; Nefs, Bas; Brandl, Bernhard
The mid-infrared (MIR) ratio [NeIII]15.6µm/[NeII]12.8µm is a strong diagnostic of the ionization state of emission-line objects, due to its use of only strong neon emission lines only weakly affected by extinction. However, this ratio is not available to ground-based telescopes as only a few spectroscopic windows …
Scaling relations of the colour-detected cluster RzCS 052 at z = 1.016 and some other high-redshift clusters
Andreon, S.; Puddu, E.; Quintana, H. +2 more
We report on the discovery of the z = 1.016 cluster RzCS 052 using a modified red-sequence method, follow up spectroscopy and X-ray imaging. This cluster has a velocity dispersion of 710 +/- 150kms-1, a virial mass of 4.0 × 1014Msolar (based on 21 spectroscopically confirmed members) and an X-ray luminosity of (0.6…
The inverse Compton X-ray-emitting lobes of the high-redshift giant radio galaxy 6C0905+39
Fabian, A. C.; Erlund, M. C.; Blundell, Katherine M.
We present new XMM-Newton data of the high-redshift (z = 1.883), Mpc-sized giant radio galaxy 6C0905+39. The larger collecting area and longer observation time for our new data means that we can better characterize the extended X-ray emission, in particular its spectrum, which arises from cosmic microwave background photons scattered into the X-ra…
Radiation effects on space-based stellar photometry: theoretical models and empirical results for CoRoT Space Telescope
Auvergne, M.; Rolland, G.; Pinheiro da Silva, L. +1 more
Convection, Rotation and planetary Transits (CoRoT) is a space mission dedicated to stellar seismology and the search for extrasolar planets. Both scientific programs are based on very high precision photometry and require long, uninterrupted observations. The instrument is based on an afocal telescope and a wide-field camera, consisting of four E…
High-energy X-ray spectra of Seyferts and Unification schemes for active galactic nuclei
Done, Chris; Middleton, Matthew; Schurch, Nick
The Unified Model of active galactic nuclei (AGN) predicts that the sole difference between type 1 and 2 Seyfert galaxies nuclei is the viewing angle with respect to an obscuring structure around the nucleus. High-energy photons above 20 keV are not affected by this absorption if the column is Compton thin, so their 30-100 keV spectra should be th…
Probing a massive radio galaxy with gravitational lensing
Muxlow, T. W. B.; McKean, J. P.; Koopmans, L. V. E. +3 more
The gravitational lens system CLASS B2108+213 has two lensed images separated by 4.56arcsec. Such a wide image separation suggests that the lens is either a massive galaxy or composed of a group of galaxies. To investigate the structure of the lensing potential we have carried out new high-resolution imaging of the two lensed images at 1.7GHz with…
The Chandra Small Magellanic Cloud Wing Survey - the search for X-ray binaries
Coe, M. J.; McBride, V. A.; McGowan, K. E. +6 more
We have detected 523 sources in a survey of the Small Magellanic Cloud (SMC) Wing with Chandra. By cross-correlating the X-ray data with optical and near-infrared catalogues, we have found 300 matches. Using a technique that combines X-ray colours and X-ray to optical flux ratios, we have been able to assign preliminary classifications to 265 of t…