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A simultaneous XMM-Newton and BeppoSAX observation of the archetypal broad line Seyfert 1 galaxy NGC 5548
Perola, G. C.; Matt, G.; Reeves, J. N. +3 more
We report the spectral analysis of a long XMM-Newton observation of the well-studied, moderate luminosity broad line Seyfert 1 galaxy NGC 5548. The source was at an historically average brightness and we find the hard (3-10 keV) spectrum can be well fitted by a power law of photon index Γ~ 1.75, together with reflection. The only feature in the ha…
The origin of the Fe K features in Markarian 205 and Markarian 509
Page, M. J.; Salvi, N. J.; Davis, S. W.
We examine the 3-10 keV EPIC spectra of Mrk 205 and 509 to investigate their Fe K features. The most significant feature in the spectra of both objects is an emission line at 6.4 keV. The spectra can be adequately modelled with a power law and a relatively narrow (σ < 0.2 keV) Fe Kα emission line. Better fits are obtained when an additional Gau…
The Tully-Fisher relation of cluster spirals at z= 0.83
Aragón-Salamanca, Alfonso; Hjorth, Jens; Milvang-Jensen, Bo +2 more
We present the rest-frame B-band Tully-Fisher relation for a sample of 8 cluster spiral galaxies at z= 0.83 and 19 field spirals at z= 0.15-0.90 based on Very Large Telescope (VLT) spectroscopy and Hubble Space Telescope (HST) photometry. No strong difference is detected between the cluster and the field galaxies, but we find some evidence that th…
Circumstellar features in hot DA white dwarfs
Barstow, M. A.; Bruhweiler, F. C.; Holberg, J. B. +1 more
We present a phenomenological study of highly ionized, non-photospheric absorption features in high spectral resolution vacuum ultraviolet spectra of 23 hot DA white dwarfs. Prior to this study, four of the survey objects (Feige 24, REJ 0457-281, G191-B2B and REJ 1614-085) were known to possess these features. We find four new objects with multipl…
The high frequency power spectrum of Markarian 766
Vaughan, S.; Fabian, A. C.
An analysis is presented of the power spectrum of X-ray variability of the bright Seyfert 1 galaxy Mrk 766 as observed by XMM-Newton. Over the 0.2-10 keV energy range the power spectral density (PSD) is well-represented by a power-law with a slope of αlow~ 1 at low frequencies, breaking to a slope of αhi= 2.8+0.2
The radio-mid-infrared correlation and the contribution of 15-µm galaxies to the 1.4-GHz source counts
Pozzi, F.; Calabrese, E.; Gruppioni, C. +5 more
The radio counterparts to the 15-µm sources in the European Large Area ISO Survey southern fields are identified in 1.4-GHz maps down to ~80 µJy. The radio-mid-infrared correlation is investigated and derived for the first time at these flux densities for a sample of this size. Our results show that radio and mid-infrared (MIR) luminos…
A two-component ionized reflection model of MCG-6-30-15
Vaughan, S.; Fabian, A. C.; Ballantyne, D. R.
Ionized reflection has often been considered as the explanation for the unusual Fe Kα variability observed in MCG-6-30-15. In this paper, we test this model using a 325-ks observation of MCG-6-30-15 by XMM-Newton and BeppoSAX. The data are fitted between 2.5 and 80 keV with the constant-density models of Ross & Fabian. The best-fitting ionized…
Core radius evolution of star clusters
Mackey, A. D.; Wilkinson, M. I.; Tout, C. A. +2 more
We use N-body simulations of star clusters to investigate the possible dynamical origins of the observed spread in core radius among intermediate-age and old star clusters in the Large Magellanic Cloud (LMC). Two effects are considered, a time-varying external tidal field and variations in primordial hard binary fraction. Simulations of clusters o…
The X-ray spectrum of the North Polar Spur
Warwick, R. S.; Snowden, S. L.; Burrows, D. N. +2 more
An analysis is presented of the soft X-ray background spectrum measured by the EPIC-MOS cameras on XMM-Newton in three observations targeted on the North Polar Spur (NPS). Three distinct Galactic plasma components are identified: a cool local hot bubble (LHB) component, Tlo~ 0.1 keV; a cool Galactic halo component, at a similar temperat…
Far-infrared photometry of deeply embedded outflow sources
Smith, M. D.; Eislöffel, J.; Froebrich, D. +1 more
We present far-infrared maps and spectroscopy for a number of deeply embedded protostellar objects (CepE, HH211-MM, IC1396 W, L1157, L1211, and RNO 15FIR) from data that we acquired with the Infrared Space Observatory (ISO) photopolarimeter (PHOT) and Long Wavelength Spectrometer (LWS). Several previously undetected deeply embedded sources are fou…