Search Publications
The XMM-Newton EPIC background and the production of background blank sky event files
Read, A. M.; Carter, J. A.
Aims:We describe in detail the nature of XMM-Newton EPIC background and its various complex components, summarising the new findings of the XMM-Newton EPIC background working group, and provide XMM-Newton background blank sky event files for use in the data analysis of diffuse and extended sources.
Methods: Blank sky event file data sets are p…
Eclipsing binaries observed with the WIRE satellite. II. β Aurigae and non-linear limb darkening in light curves
Southworth, J.; Bruntt, H.; Buzasi, D. L.
Aims:We present the most precise light curve ever obtained of a detached eclipsing binary star and use it investigate the inclusion of non-linear limb darkening laws in light curve models of eclipsing binaries. This light curve, of the bright eclipsing system β Aurigae, was obtained using the star tracker aboard the wire satellite and contains 30 …
On the Iwasawa-Taniguchi effect of radio-quiet AGN
Bianchi, S.; Guainazzi, M.; Matt, G. +1 more
Aims:The existence of an anti-correlation between the Equivalent Width (EW) of the neutral narrow core of the iron Kα emission line and the 2-10 keV luminosity (the so-called "X-ray Baldwin" or "Iwasawa-Taniguchi" effect) has been debated in the last years. We aim at testing this claim on the largest catalogue of radio quiet AGN high-quality X-ray…
Candidate tidal disruption events from the XMM-Newton slew survey
Altieri, B.; Sanchez-Portal, M.; Read, A. M. +4 more
Context: In recent years, giant amplitude X-ray flares have been observed from a handful of non-active galaxies. The most plausible scenario of these unusual phenomena is tidal disruption of a star by a quiescent supermassive black hole at the centre of the galaxy.
Aims: Only a small number of these type of events have been observed and confir…
The peculiar horizontal branch morphology of the Galactic globular clusters NGC 6388 and NGC 6441: new insights from UV observations
Djorgovski, S. G.; Zoccali, M.; Busso, G. +9 more
Context: In this paper we present multiband optical and UV Hubble Space Telescope photometry of the two Galactic globular clusters
Aims: We investigate the properties of their anomalous horizontal branches in different photometric planes in order to shed light on the nature of the ph…
A multi-wavelength study of z = 3.15 Lyman-α emitters in the GOODS South Field
Watson, D.; Fynbo, J. P. U.; Rosati, P. +7 more
Context: Lyα-emitters have proven to be excellent probes of faint, star-forming galaxies in the high redshift universe. However, although the sample of known emitters is increasingly growing, their nature (e.g. stellar masses, ages, metallicities, star-formation rates) is still poorly constrained.
Aims: We aim to study the nature of Lyα-emitte…
First numerical ephemerides of the Martian moons
Pätzold, M.; Lainey, V.; Dehant, V.
We present new ephemerides of Phobos and Deimos that are fit to observations from 1877 to 2005 and include recent spacecraft observations by Mars Global Surveyor and Mars Express. In contrast to earlier models, this is the first completely numerical one. In particular, the tidal effects have been modeled by the tidal bulge raised by each moon on t…
The luminosity function of high-redshift quasi-stellar objects. A combined analysis of GOODS and SDSS
Brandt, W. N.; Vanzella, E.; Grazian, A. +5 more
Aims:In this work the luminosity function of QSOs is measured in the redshift range 3.5<z<5.2 for the absolute magnitude interval -21<M145<-28. Determining the faint-end of the luminosity function at these redshifts provides important constraints on models of the joint evolution of galaxies and AGNs.
Methods: We have def…
Signatures of synchrotron emission and of electron acceleration in the X-ray spectra of Mrk 421
Tramacere, A.; Massaro, F.; Cavaliere, A.
Context: BL Lac objects undergo strong flux variations involving considerable changes in their spectral shapes. We specifically investigate the X-ray spectral evolution of Mrk 421 over a time span of about nine years.
Aims: We aim at statistically describing and physically understanding the large spectral changes in X rays observed in Mrk 421 …
Hard X-ray emission from the Galactic ridge
Sunyaev, R.; Krivonos, R.; Revnivtsev, M. +3 more
We present results of a study of the Galactic ridge X-ray emission (GRXE) in hard X-rays performed with the IBIS telescope aboard INTEGRAL. The imaging capabilities of this coding aperture telescope make it possible to account for the flux from bright Galactic point sources whereas the wide field of view permits us to collect large flux from the u…