Search Publications
Synthetic stellar populations: single stellar populations, stellar interior models and primordial protogalaxies
Jimenez, Raul; Dunlop, James S.; Peacock, John A. +2 more
We present a new set of stellar interior and synthesis models for predicting the integrated emission from stellar populations in star clusters and galaxies of arbitrary age and metallicity. This work differs from existing spectral synthesis codes in a number of important ways, namely (1) the incorporation of new stellar evolutionary tracks, with s…
Deep SAURON spectral imaging of the diffuse Lyman α halo LAB1 in SSA 22
Sullivan, M.; Chapman, S.; Bower, R. G. +6 more
We have used the SAURON panoramic integral field spectrograph to study the structure of the Lyα emission-line halo, LAB1, surrounding the submillimetre galaxy SMM J221726+0013. This emission-line halo was discovered during a narrow-band imaging survey of the z= 3.1 large-scale structure in the SSA 22 region. Our observations trace the emission hal…
Measurements of accretion disc corona size in LMXB: consequences for Comptonization and LMXB models
Church, M. J.; Bałucińska-Church, M.
We present results of measurements of the radial extent of the accretion disc corona in low-mass X-ray binaries (LMXB), i.e. of the radial extent of the thin, hot ADC above the accretion disc. These results prove conclusively the extended nature of the ADC, with radial extent varying from 20 000 km in the faintest sources to 700 000 km in the brig…
The (un)resolved X-ray background in the Lockman Hole
Barcons, X.; Fabian, A. C.; Hasinger, G. +3 more
Most of the soft and a growing fraction of the harder X-ray background has been resolved into emission from point sources, yet the resolved fraction above 7 keV has only been poorly constrained. We use ~700 ks of XMM-Newton observations of the Lockman Hole and a photometric approach to estimate the total flux attributable to resolved sources in a …
A multiply imaged, submillimetre-selected ultraluminous infrared galaxy in a galaxy group at z~ 2.5
Smail, Ian; Kneib, Jean-Paul; van der Werf, Paul P. +5 more
We present observations of a remarkable submillimetre-selected galaxy, SMM J16359+6612. This distant galaxy lies behind the core of a massive cluster of galaxies, A 2218, and is gravitationally lensed by the foreground cluster into three discrete images which were identified in deep submillimetre maps of the cluster core at both 450 and 850 µ…
Long-term spectral changes in the partial-covering candidate narrow-line Seyfert 1 galaxy 1H 0707-495
Brandt, W. N.; Vaughan, S.; Fabian, A. C. +3 more
We compare two XMM-Newton observations of the narrow-line Seyfert 1 galaxy 1H 0707-495, separated by two years, and discuss the results in terms of the partial-covering phenomenon. The second longer observation once again displays a sharp (<200 eV) spectral drop above 7 keV; however, in comparison with the first observation, the edge depth and …
X-ray source populations in the Galactic plane
Warwick, R. S.; Watson, M. G.; Helfand, D. J. +1 more
We present the first results from the XMM-Newton Galactic Plane Survey (XGPS). In the first phase of the programme, 22 pointings were used to cover a region of approximately 3 deg2 between 19° and 22° in Galactic longitude and +/-0.6° in latitude. In total we have resolved over 400 point X-ray sources, at >= 5σ significance, down to …
Relativistic spectral features from X-ray-illuminated spots and the measure of the black hole mass in active galactic nuclei
Bianchi, S.; Guainazzi, M.; Matt, G. +2 more
Narrow spectral features in the 5-6 keV range were recently discovered in the X-ray spectra of a few active galactic nuclei. We discuss the possibility that these features are due to localized spots which occur on the surface of an accretion disc following its illumination by flares. We present detailed line profiles as a function of orbital phase…
Far-infrared and submillimetre observations of the Crab nebula
Tuffs, R. J.; Popescu, C. C.; Green, D. A.
We present far-infrared (FIR) and submillimetre images of the Crab nebula, taken with the ISOPHOT instrument onboard the Infrared Space Observatory (ISO) and with the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope. The ISOPHOT observations were made in the bands centred at 60, 100 and 170 µm, with FWHM…
The energy balance of polars revisited
Cropper, Mark; Ramsay, Gavin
In the EXOSAT and ROSAT eras, a significant number of polars were found to show a soft/hard X-ray ratio much greater than that expected from the standard accretion shock model. This was known as the `soft X-ray excess'. We have made an snapshot survey of polars using XMM-Newton and determined their soft/hard ratios. We find that less than one in f…