Search Publications
On the compact nature of the most luminous ULX in the Cartwheel ring
Trinchieri, Ginevra; Wolter, Anna; Colpi, Monica
We report the first detection of flux variability in the most luminous X-ray source in the southern ring of the Cartwheel galaxy. XMM-Newton data show that the luminosity has varied over a time-scale of 6 months from L0.5-10keV ~ 1.3 × 1041ergs-1, consistent with the previous Chandra observation, to L0.5-10keV…
Discovery of a relativistic Fe line in PG 1425+267 with XMM-Newton and study of its short time-scale variability
Fabian, A. C.; Miniutti, G.
We report results from the XMM-Newton observation of the radio-loud quasar PG 1425+267 (z= 0.366). The X-ray data above 2keV exhibit a double-peaked emission feature in the Fe K band. The higher energy peak is found at 6.4keV and is consistent with being narrow, while the lower energy one is detected at 5.3keV and is much broader than the detector…
The massive star population in the giant HII region Tol89 in NGC5398
Smith, Linda J.; Crowther, Paul A.; Sidoli, Fabrizio
We present new high spectral resolution Very Large Telescope (VLT)/UV-Visual Echelle Spectrograph (UVES) spectroscopy and archival Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) imaging and spectroscopy of the giant HII region Tol89 in NGC5398. From optical and ultraviolet (UV) HST images, we find that the star-forming co…
Near-infrared imaging polarimetry of dusty young stars
Barlow, M. J.; Gledhill, T. M.; Lowe, K. T. E. +1 more
We have carried out JHK polarimetric observations of 11 dusty young stars, by using the polarimeter module IRPOL2 with the near-infrared camera UIST on the 3.8-m United Kingdom Infrared Telescope (UKIRT). Our sample targeted systems for which UKIRT-resolvable discs had been predicted by model fits to their spectral energy distributions. Our observ…
Can the unresolved X-ray background be explained by the emission from the optically-detected faint galaxies of the GOODS project?
Lehmer, B. D.; Alexander, D. M.; Bauer, F. E. +3 more
The emission from individual X-ray sources in the Chandra Deep Fields and XMM-Newton Lockman Hole shows that almost half of the hard X-ray background above 6keV is unresolved and implies the existence of a missing population of heavily obscured active galactic nuclei (AGN). We have stacked the 0.5-8keV X-ray emission from optical sources in the Gr…
Tracing gas motions in the Centaurus cluster
Fabian, A. C.; Sanders, J. S.; Morris, R. G. +1 more
We apply the stochastic model of iron transport developed by Rebusco et al. to the Centaurus cluster. Using this model, we find that an effective diffusion coefficient D in the range 2 × 1028-4 × 1028cm2s-1 can approximately reproduce the observed abundance distribution. Reproducing the flat central prof…
X-ray reflection in the nearby Seyfert 2 galaxy NGC 1068
Vaughan, Simon; Pounds, Ken
We use the full broad-band XMM-Newton European Photon Imaging Camera (EPIC) data to examine the X-ray spectrum of the nearby Seyfert 2 galaxy NGC 1068, previously shown to be complex with the X-ray continuum being a sum of components reflected/scattered from cold (neutral) and warm (ionized) matter, together with associated emission-line spectra. …
Failed disc winds: a physical origin for the soft X-ray excess?
Schurch, N. J.; Done, C.
The origin of the soft X-ray excess emission observed in many type-1 active galactic nuclei (AGN) has been an unresolved problem in X-ray astronomy for over two decades. We develop the model proposed by Gierliński & Done, which models the soft excess with heavily smeared, ionized, absorption, by including the emission that must be associated w…
An XMM-Newton observation of the massive edge-on Sb galaxy NGC 2613
Wang, Q. D.; Li, Z.; Irwin, J. A. +1 more
We present an XMM-Newton observation of the massive edge-on Sb galaxy NGC 2613. We discover that this galaxy contains a deeply embedded active nucleus with a 0.3-10 keV luminosity of 3.3 × 1040ergs-1 and a line-of-sight absorption column of 1.2 × 1023cm-2. Within the 25 magarcsec-2 optical B-b…
NGC 4435: a bulge-dominated galaxy with an unforeseen low-mass central black hole
Dalla Bontà, E.; Corsini, E. M.; Pizzella, A. +3 more
We present the ionized gas kinematics of the SB0 galaxy NGC 4435 from spectra obtained with the Space Telescope Imaging Spectrograph. This galaxy has been selected on the basis of its ground-based spectroscopy, for displaying a position-velocity diagram consistent with the presence of a circumnuclear Keplerian disc rotating around a supermassive b…