Search Publications
Strong magnetic asymmetries in weakly interacting spirals
Ehle, M.; Beck, R.; Chyży, K. T.
We investigate the influence of cluster environment on the structure and evolution of magnetic fields and the interstellar medium in the Virgo cluster spiral NGC 4254. Our sensitive interferometric (VLA) and single dish (Effelsberg) radio polarimetric observations reveal several magnetic spiral arms displaced from optical ones. However, the southe…
Variability of the Fe K line relativistic component in a sample of Seyfert 1 galaxies
Cappi, M.; Dadina, M.; De Marco, B. +1 more
We present the analysis of X-ray spectral variability made on a sample of 7 Seyfert 1 bright galaxies, using XMM-Newton data. From the ``XMM-Newton Science Archive'' we selected those bright Seyfert 1 showing one or more prominent flares in their 2-10 keV light curves. For each of them we extracted spectra in 3 different time intervals: before, du…
Search for narrow energy-shifted lines in AGN spectra in the XMM-Newton archive
Bianchi, S.; Guainazzi, M.; Santos-Lleo, M. +2 more
Thanks to the large effective area and the spectral resolution of current X-ray satellites, the detection of X-ray narrow spectral features in the 5-7 keV band is becoming commonplace in many AGN observations. Such lines, both in emission and in absorption, are mostly interpreted as arising from Iron atoms. When observed with some displacement fro…
Fourier-resolved spectroscopy of AGN using XMM-Newton data
Papadakis, I. E.; Kazanas, D.; Ioannou, Z.
% We present a brief account of the theory on which the novel method of `Fourier-resolved spectroscopy' is based. We summarize the results from the past application of this method to the study of Galactic Black Hole candidate sources and MCG-6-30-15, and we present new results from the Fourier-resolved spectroscopy of archival XMM-Newton data of f…
XMM-Newton detection of relativistic Fe emission in the X-ray spectrum of SAX J1711.6-3808
Altieri, B.; Santos-Lleó, M.; Sánchez-Fernández, C. +4 more
The transient system SAX J1711.6-3808 was observed by XMM-Newton during its 2001 outburst, when the source was close to its maximum outburst luminosity. Our observations show that the broad Fe emission line detected in this outburst by In' t Zand et al. (\cite{intZand02}) has indeed a relativistic nature, suggesting that SAX J1711.6-3808 harbors a…
Relativistic Fe Kα features in the XMM-Newton spectrum of the intermediate Seyfert galaxy 4U 1344-60
Bianchi, S.; Guainazzi, M.; Jiménez-Bailón, E. +6 more
We present the analysis of optical and X-ray XMM-Newton data of the source 4U 1344-60. On the basis of the optical data we propose to classify 4U 1344-60 as a Seyfert 1.5 galaxy and we measured a redshift value z=0.012±0.001. The observed X-ray spectrum is complex. The continuum emission can be described as a power law obscured by two neutral abso…
HST/ACS observations of Lyman-break galaxies and Lyα emitters associated with radio galaxies at z>4
Overzier, R. A.
Distant radio galaxies may pinpoint overdense regions in the early universe. We have collected data with HST/ACS towards several overdensities of Lyα emitters associated with radio galaxies discovered by Venemans et al. Using the Lyman break selection technique we find statistical evidence for additional galaxies associated with the radio galaxies…
Relativistic Fe line emission and highly photoionized absorption in GRO J1655-40
Díaz Trigo, M.; Miller, J. M.; Kuulkers, E. +1 more
We report on two XMM-Newton and simultaneous INTEGRAL observations of the microquasar GRO J1655-40 during its 2005 outburst. The source was most probably in its high-soft state during both observations. There is evidence for the presence of both a relativistically broadened Fe line providing strong support for the existence of a spinning black hol…
XMM-Newton monitoring observations of Mrk 3
Nandra, K.; Georgantopoulos, I.; Akylas, A.
We present monitoring analysis of 8 XMM-Newton observations of the Seyfert 2 galaxy Mrk 3, spanning a period of ∼19 months. The continuum flux in the 3-12 keV band remains constant during this observing period. The X-ray spectrum is well described, in agreement with previous works, by a highly absorbed (N_H>1024 cm-2) powe…
The Japanese X-ray missions
Fujita, Y.
Here, I briefly introduce Japanese X-ray missions: Suzaku and NeXT. Suzaku was launched on July 10, 2005. NeXT will be launched in 2011. They will open new windows into the workings of black holes, clusters of galaxies, active galaxies, and other very energetic objects.