Martin J. L. Turner
University of Leicester
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Astronomy and Astrophysics | 2001
Martin J. L. Turner; A. F. Abbey; M. Arnaud; M. Balasini; M. Barbera; E. Belsole; P. J. Bennie; J. P. Bernard; G. F. Bignami; M. Boer; Ulrich G. Briel; I. Butler; Christophe Cara; C. Chabaud; Richard E. Cole; A. Collura; M. Conte; A. Cros; M. Denby; P. Dhez; G. Di Coco; J. Dowson; P. Ferrando; S. Ghizzardi; F. Gianotti; C. V. Goodall; L. Gretton; R. G. Griffiths; O. Hainaut; J. F. Hochedez
The EPIC focal plane imaging spectrometers on XMM-Newton use CCDs to record the images and spectra of celestial X-ray sources focused by the three X-ray mirrors. There is one camera at the focus of each mirror; two of the cameras contain seven MOS CCDs, while the third uses twelve PN CCDs, dening a circular eld of view of 30 0 diameter in each case. The CCDs were specially developed for EPIC, and combine high quality imaging with spectral resolution close to the Fano limit. A lter wheel carrying three kinds of X-ray transparent light blocking lter, a fully closed, and a fully open position, is tted to each EPIC instrument. The CCDs are cooled passively and are under full closed loop thermal control. A radio-active source is tted for internal calibration. Data are processed on-board to save telemetry by removing cosmic ray tracks, and generating X-ray event les; a variety of dierent instrument modes are available to increase the dynamic range of the instrument and to enable fast timing. The instruments were calibrated using laboratory X-ray beams, and synchrotron generated monochromatic X-ray beams before launch; in-orbit calibration makes use of a variety of celestial X-ray targets. The current calibration is better than 10% over the entire energy range of 0.2 to 10 keV. All three instruments survived launch and are performing nominally in orbit. In particular full eld-of-view coverage is available, all electronic modes work, and the energy resolution is close to pre-launch values. Radiation damage is well within pre-launch predictions and does not yet impact on the energy resolution. The scientic results from EPIC amply full pre-launch expectations.
Monthly Notices of the Royal Astronomical Society | 2003
K. A. Pounds; J. N. Reeves; A. R. King; Kim L. Page; Paul T. O'Brien; Martin J. L. Turner
The definitive version is available from www.blackwell-synergy.com. Erratum published in Monthly Notices of the Royal Astronomical Society, 2005, 356, p.1599
Astronomy and Astrophysics | 2001
G. Hasinger; B. Altieri; M. Arnaud; X. Barcons; Jacqueline Bergeron; H. Brunner; M. Dadina; K. Dennerl; P. Ferrando; Alexis Finoguenov; Richard E. Griffiths; Yasuhiro Hashimoto; F. Jansen; D. Lumb; K. O. Mason; S. Mateos; Richard G. McMahon; Takamitsu Miyaji; Frits Paerels; Mat Page; Af Ptak; Timothy P. Sasseen; N. Scharte; Gyula Pal Szokoly; J. Trümper; Martin J. L. Turner; R. S. Warwick; M. G. Watson
We report on the first deep X-ray survey with the XMM-Newton observatory during the performance verification phase. The field of the Lockman Hole, one of the best studied sky areas over a very wide range of wavelengths, has been observed. A total of ~100 ksec good exposure time has been accumulated. Combining the images of the European Photon Imaging Camera (EPIC) detectors we reach a flux limit of 0.31, 1.4 and
Nature | 2002
J. N. Reeves; D. Watson; Julian P. Osborne; K. A. Pounds; Paul T. O'Brien; A. Short; Martin J. L. Turner; M. G. Watson; K. O. Mason; M. Ehle; Norbert Schartel
2.4 10^{-15} {\rm erg} {\rm cm}^{-2} {\rm s}^{-1}
Monthly Notices of the Royal Astronomical Society | 2004
Kim L. Page; Paul T. O'Brien; J. N. Reeves; Martin J. L. Turner
, respectively in the 0.5-2, 2-10, and 5-10 keV band. Within an off-axis angle of 10 arcmin we detect 148, 112 and 61 sources, respectively. The log( N )-log( S ) relation in the three bands is compared with previous results. In particular in the 5-10 keV band these observations present the deepest X-ray survey ever, about a factor 20 more sensitive than the previous BeppoSAX observations. Using X-ray spectral diagnostics and the set of previously known, spectroscopically identified ROSAT sources in the field, the new sources can be classified. XMM-Newton detects a significant number (~40% ) of X-ray sources with hard, probably intrinsically absorbed X-ray spectra, confirming a prediction of the population synthesis models for the X-ray background.
Monthly Notices of the Royal Astronomical Society | 2005
Kim L. Page; J. N. Reeves; Paul T. O'Brien; Martin J. L. Turner
Now that γ-ray bursts (GRBs) have been determined to lie at cosmological distances, their isotropic burst energies are estimated to be as high as 1054 erg (ref. 2), making them the most energetic phenomena in the Universe. The nature of the progenitors responsible for the bursts remains, however, elusive. The favoured models range from the merger of two neutron stars in a binary system to the collapse of a massive star. Spectroscopic studies of the afterglow emission could reveal details of the environment of the burst, by indicating the elements present, the speed of the outflow and an estimate of the temperature. Here we report an X-ray spectrum of the afterglow of GRB011211, which shows emission lines of magnesium, silicon, sulphur, argon, calcium and possibly nickel, arising in metal-enriched material with an outflow velocity of the order of one-tenth the speed of light. These observations strongly favour models where a supernova explosion from a massive stellar progenitor precedes the burst event and is responsible for the outflowing matter.
The Astrophysical Journal | 2001
R. Edelson; Gareth Griffiths; A. Markowitz; Steve Sembay; Martin J. L. Turner; R. S. Warwick
The majority of active galactic nuclei (AGN) observed by XMM-Newton reveal narrow Fe Ka lines at ∼6.4 keV, due to emission from cold (neutral) material. There is an X-ray Baldwin effect in type I AGN, in that the equivalent width (EW) of the line decreases with increasing luminosity, with weighted linear regression giving EW L -0.17±0.08 (Spearman Rank probability of >99.9 per cent). With current instrumental capabilities it is not possible to determine the precise origin for the narrow line, with both the broad-line region and putative molecular torus being possibilities. A possible explanation for the X-ray Baldwin effect is a decrease in the covering factor of the material forming the fluorescence line.
SPIE's International Symposium on Optical Science, Engineering, and Instrumentation | 1998
A. Short; Adam Keay; Martin J. L. Turner
XMM‐Newton observations of 29 high-redshift (z > 2) quasars, including seven radio-quiet, 16 radio-loud and six broad absorption line (BAL) objects, are presented; due to the high redshifts, the rest-frame energy bands extend up to ∼30‐70 keV. Over 2‐10 keV, the quasars can be well fitted in each case by a simple power law, with no strong evidence for iron emission lines. The lack of iron lines is in agreement both with dilution by the radio jet emission (for the radio-loud quasars) and the X-ray Baldwin effect. No Compton reflection humps at higher energies (i.e. above 10 keV in the rest frame) are detected either. Over the broad-band (0.3‐ 10 keV), approximately half (nine out of 16) of the radio-loud quasars are intrinsically absorbed, with the values of NH generally being 1 × 10 22 to 2 × 10 22 cm −2 in the rest frames of the objects. None of the seven radio-quiet objects shows excess absorption, while four of the six BAL quasars are absorbed. The radio-loud quasars have flatter continuum slopes than their radio-quiet counterparts (� RL ∼ 1.55; � RQ ∼ 1.98 over 2‐10 keV), while, after modelling the absorption, the underlying photon index for the six BAL quasars is formally consistent with the non-BAL radio-quiet objects. Ke yw ords: galaxies: active ‐ quasars: general ‐ X-rays: galaxies.
Monthly Notices of the Royal Astronomical Society | 2004
Kim L. Page; Martin J. L. Turner; Chris Done; Paul T. O'Brien; J. N. Reeves; S. Sembay; M. Stuhlinger
The bright, strongly variable BL Lac object PKS 2155-304 was observed by XMM for two essentially uninterrupted periods of ~11 and 16 hr on 30-31 May 2000. The strongest variations occurred in the highest energy bands. After scaling for this effect, the three softest bands (0.1-1.7 keV) showed strong correlation with no measurable lag to reliable limits of
Monthly Notices of the Royal Astronomical Society | 2004
Kim L. Page; J. N. Reeves; Paul T. O'Brien; Martin J. L. Turner; Diana M Worrall
\tau \ls 0.3