Search Publications
The spectral energy distributions of the revised 200-mJy sample
Bondi, M.; Browne, I. W. A.; Antón, S. +2 more
We address the question of why low-luminosity radio sources with similar flat radio spectra show a range of optical activity. The investigation is based on the spectral energy distributions (SEDs) of objects from the 200-mJy sample. We gathered new data from the VLA at 43 GHz, from SCUBA in the JCMT at 2000, 1350 and 850 µm, and from the ISO…
An XMM-Newton view of M101 - I. The luminous X-ray source population
Warwick, R. S.; Roberts, T. P.; Ward, M. J. +2 more
We present the first results of an XMM-Newton EPIC observation of the luminous X-ray source population in the face-on supergiant spiral galaxy M101. We have studied the spectral and temporal properties of the 14 most luminous sources, all of which have intrinsic X-ray luminosities exceeding the Eddington limit for a 1.4-Msolar neutron s…
Why does the intermediate polar V405 Aurigae show a double-peaked spin pulse?
Hellier, Coel; Evans, P. A.
V405 Aurigae is an intermediate polar showing a double-peaked pulsation in soft X-rays and a single-peaked pulsation in harder X-rays. From XMM-Newton observations, we find that the soft band is dominated by blackbody emission from the heated white dwarf surface. Such emission is at a maximum when either magnetic pole points towards us, explaining…
Chandra observations of five X-ray transient galactic nuclei
Vaughan, S.; Warwick, R. S.; Edelson, R.
We report on exploratory Chandra observations of five galactic nuclei that were found to be X-ray bright during the ROSAT All-Sky Survey (with LX>~ 1043 erg s-1) but subsequently exhibited a dramatic decline in X-ray luminosity. Very little is known about the post-outburst X-ray properties of these enigmatic sou…
The hard X-ray spectrum of the Seyfert galaxy IRAS 18325-5926: reflection from an ionized disc and variable iron K emission
Young, A. J.; Iwasawa, K.; Fabian, A. C. +2 more
We report our analysis of the X-ray spectra of the Seyfert galaxy IRAS 18325-5926 (= Fairall 49) obtained from various X-ray observatories prior to XMM-Newton, including new results from two RXTE and one BeppoSAX observations. A relatively steep continuum slope (Γ~= 2.2) in the 2-15 keV band is confirmed. The continuum spectrum observed with the B…
Spatially extended K Iλ7699 emission in the nebula of VY CMa: kinematics and geometry
Smith, Nathan
Long-slit echelle spectra reveal bright extended emission from the K Iλ7699 resonance line in the reflection nebula surrounding the extreme red supergiant VY Canis Majoris. The central star has long been known for its unusually bright K I emission lines, but this is the first report of intrinsic emission from K I in the nebula. The extended emissi…
An XMM-Newton observation of the nova-like variable UX UMa: spatially and spectrally resolved two-component X-ray emission
Mukai, K.; Pratt, G. W.; Hassall, B. J. M. +2 more
In the optical and ultraviolet regions of the electromagnetic spectrum, UX Ursae Majoris is a deeply eclipsing cataclysmic variable. However, no soft X-ray eclipse was detected in ROSAT observations. We have obtained a 38 ksec XMM-Newton observation to constrain further the origin of the X-rays. The combination of spectral and timing information a…
Ionized gas and stars in the central kiloparsec of the type 2 Seyfert galaxy NGC 2110 - I. The data
Schinnerer, E.; Wilson, A. S.; Emsellem, E. +4 more
In this paper, we present new results from an extensive set of Hubble Space Telescope (HST) and ground-based observations of the Seyfert galaxy NGC 2110. The HST data sets include Wide Field Planetary Camera 2 (WFPC2) observations as well as the first high-spatial resolution spectroscopy ([OI], [NII], Hα and [SII] lines) of this galaxy obtained us…
The X-ray, optical and radio evolution of the GRB 030329 afterglow and the associated SN2003dh
O'Brien, P. T.; Osborne, J. P.; Page, K. L. +3 more
Extensive X-ray, optical and radio observations of the bright afterglow of the gamma-ray burst GRB 030329 are used to construct the multifrequency evolution the event. The data are fitted using the standard fireball shock model to provide estimates of the initial energy, ɛ= 6.8 × 1052 erg sr-1, the density of the ambient medi…
Twisted accretion curtains in the intermediate polar FO Aquarii
Cropper, Mark; Hellier, Coel; Ramsay, Gavin +1 more
We report on a ~37-ks XMM-Newton observation of the intermediate polar FO Aquarii, presenting X-ray and ultraviolet data from the EPIC and OM cameras. We find that the system has changed from its previously reported state of disc-overflow accretion to one of purely disc-fed accretion. We detect the previously reported `notch' feature in the X-ray …