Search Publications

Evidence for orbital motion of material close to the central black hole of Mrk 766
DOI: 10.1051/0004-6361:20053042 Bibcode: 2006A&A...445...59T

Turner, T. J.; Reeves, J. N.; George, I. M. +1 more

Time-resolved X-ray spectroscopy has been obtained for the narrow line Seyfert galaxy Mrk 766 from XMM-Newton observations. We present analysis in the energy-time plane of EPIC pn data in the 4-8 keV band with energy resolution R ≃ 50. A component of Fe Kα emission detected in the maps shows a variation of photon energy with time that appears both…

2006 Astronomy and Astrophysics
XMM-Newton 63
Simultaneous X-ray and optical observations of S5 0716+714 after the outburst of March 2004
DOI: 10.1051/0004-6361:20064959 Bibcode: 2006A&A...455..871F

Maraschi, L.; Tagliaferri, G.; Ghisellini, G. +6 more

At the end of March 2004, the blazar S5 0716+714 underwent an optical outburst that prompted for quasi-simultaneous target-of-opportunity observations with the INTEGRAL and XMM-Newton satellites. In this paper, we report the results of the XMM-Newton and INTEGRAL OMC data analysis. The X-ray spectrum is well-represented by a concave broken power-l…

2006 Astronomy and Astrophysics
INTEGRAL XMM-Newton 63
Tracing baryons in the warm-hot intergalactic medium with broad Ly α absorption
DOI: 10.1051/0004-6361:20053636 Bibcode: 2006A&A...445..827R

Savage, B. D.; Sembach, K. R.; Richter, P. +1 more

We discuss physical properties and baryonic content of broad Ly α absorbers (BLAs) at low redshift. These absorption systems, recently discovered in high-resolution, high-signal to noise quasar absorption line spectra, possibly trace the warm-hot intergalactic medium (WHIM) in the temperature range between 105 and 106 K. The …

2006 Astronomy and Astrophysics
eHST 62
XMM-Newton observation of a spectral state transition in the peculiar radio/X-ray/γ-ray source LS I +61 303
DOI: 10.1051/0004-6361:20065933 Bibcode: 2006A&A...459..901S

Mereghetti, S.; Sidoli, L.; Pellizzoni, A. +3 more

We report the results of XMM-Newton and BeppoSAX observations of the radio and X-ray emitting star LS I +61 303, likely associated with the gamma-ray source 2CG 135+01 and recently detected also at TeV energies. The data include a long XMM-Newton pointing carried out in January 2005, which provides the deepest look ever obtained for this object in…

2006 Astronomy and Astrophysics
XMM-Newton 62
The X-ray emission of the supernova remnant W49B observed with XMM-Newton
DOI: 10.1051/0004-6361:20054290 Bibcode: 2006A&A...453..567M

Ballet, J.; Miceli, M.; Bocchino, F. +4 more

Context.In the framework of the study of supernova remnants and their complex interaction with the interstellar medium, we report on an XMM-Newton EPIC observation of the Galactic supernova remnant W49B.
Aims.We investigated the spatial distribution of the chemical and physical properties of the plasma, so as to get important constraints on the…

2006 Astronomy and Astrophysics
XMM-Newton 62
XMM-Newton high-resolution spectroscopy reveals the chemical evolution of M 87
DOI: 10.1051/0004-6361:20065678 Bibcode: 2006A&A...459..353W

Böhringer, H.; Simionescu, A.; Kaastra, J. S. +3 more

We present a study of chemical abundances in the giant elliptical galaxy M 87 using high-resolution spectra obtained with the Reflection Grating Spectrometers during two deep XMM-Newton observations. While we confirm the two-temperature structure of the inter-stellar medium (ISM) in M 87, we also show that a continuous temperature distribution des…

2006 Astronomy and Astrophysics
XMM-Newton 61
Multifrequency VLBA monitoring of 3C 273 during the INTEGRAL Campaign in 2003. I. Kinematics of the parsec scale jet from 43 GHz data
DOI: 10.1051/0004-6361:20053753 Bibcode: 2006A&A...446...71S

Tornikoski, M.; Wiik, K.; Savolainen, T. +1 more

In this first of a series of papers describing polarimetric multifrequency Very Long Baseline Array (VLBA) monitoring of 3C 273 during a simultaneous campaign with the INTEGRAL γ-ray satellite in 2003, we present 5 Stokes I images and source models at 7 mm. We show that a part of the inner jet (1-2 milliarcsec from the core) is …

2006 Astronomy and Astrophysics
INTEGRAL 61
Hubble Space Telescope observations of the nucleus and inner coma of comet 67P/Churyumov-Gerasimenko
DOI: 10.1051/0004-6361:20065253 Bibcode: 2006A&A...458..669L

Jorda, L.; Lamy, P. L.; Gutiérrez, P. J. +3 more

Context: .Following the postponement of the launch of the Rosetta spacecraft scheduled in January 2003, comet 67P/Churyumov-Gerasimenko emerged as the most suitable new target. However a critical issue was the size, that is, the mass of its nucleus, as the surface module Philae was designed to land on a nucleus with a radius no larger than approxi…

2006 Astronomy and Astrophysics
Rosetta eHST 60
A hard X-ray view of giga-hertz peaked spectrum radio galaxies
DOI: 10.1051/0004-6361:20053374 Bibcode: 2006A&A...446...87G

Guainazzi, M.; Piconcelli, E.; Grandi, P. +3 more

We present the first broadband X-ray observations of four Giga-Hertz Peaked Spectrum (GPS) radio galaxies at redshift ⪉1 performed by Chandra and XMM-Newton. These observations more than double the number of members of this class with measured spectra in hard (E > 2 keV) X-rays. All sources were detected. Their radio-to-X-ray spectral energy di…

2006 Astronomy and Astrophysics
XMM-Newton 59
Unveiling the nature of INTEGRAL objects through optical spectroscopy. IV. A study of six new hard X-ray sources
DOI: 10.1051/0004-6361:20065111 Bibcode: 2006A&A...455...11M

Palazzi, E.; Masetti, N.; Walter, R. +9 more

We present further results from our onging optical spectrophotometric campaign at the Astronomical Observatory of Bologna in Loiano (Italy) on unidentified hard X-ray sources detected by INTEGRAL. We observed spectroscopically the putative optical counterparts of the INTEGRAL sources IGR J00234+6141, IGR J01583+6713, IGR J06074+2205, IGR J13091+11…

2006 Astronomy and Astrophysics
INTEGRAL 59