Search Publications
An X-Ray Study of Magnetic Field Strengths and Particle Content in the Lobes of FR II Radio Sources
Hardcastle, M. J.; Croston, J. H.; Birkinshaw, M. +3 more
We present a Chandra and XMM-Newton study of X-ray emission from the lobes of 33 classical double radio galaxies and quasars. We report new detections of lobe-related X-ray emission in 11 sources. Together with previous detections, we find that X-ray emission is detected from at least one radio lobe in ~75% of the sample. For all of the lobe detec…
Reflections of Active Galactic Nucleus Outbursts in the Gaseous Atmosphere of M87
Churazov, E.; Vikhlinin, A.; Forman, W. +7 more
We combined deep Chandra, ROSAT HRI, and XMM-Newton observations of M87 to study the impact of active galactic nucleus (AGN) outbursts on its gaseous atmosphere. Many X-ray features appear to be a direct result of repetitive AGN outbursts. In particular, the X-ray cavities around the jet and counterjet are likely due to the expansion of radio plas…
Rapid Compton-thick/Compton-thin Transitions in the Seyfert 2 Galaxy NGC 1365
Zezas, A.; Elvis, M.; Baldi, A. +2 more
We present multiple Chandra and XMM-Newton observations of the type 1.8 Seyfert galaxy NGC 1365, which shows the most dramatic X-ray spectral changes observed so far in an active galactic nucleus: the source switched from reflection-dominated to transmission-dominated and back in just 6 weeks. During this time the soft thermal component, arising f…
The Relationship of Hard X-Ray and Optical Line Emission in Low-Redshift Active Galactic Nuclei
Ptak, A.; Heckman, T. M.; Hornschemeier, A. +1 more
In this paper we assess the relationship of the population of active galactic nuclei (AGNs) selected by hard X-rays to the traditional population of AGNs with strong optical emission lines. First, we study the emission-line properties of a new hard-X-ray-selected sample of 47 local AGNs (classified optically as Type 1 and 2 AGNs). We find that the…
Relativistic Accretion Disk Models of High-State Black Hole X-Ray Binary Spectra
Hubeny, Ivan; Davis, Shane W.; Turner, Neal J. +1 more
We present calculations of non-LTE, relativistic accretion disk models applicable to the high/soft state of black hole X-ray binaries. We include the effects of thermal Comptonization and bound-free and free-free opacities of all abundant ion species. Taking into account the relativistic propagation of photons from the local disk surface to an obs…
Discovery of an X-Ray-luminous Galaxy Cluster at z=1.4
Böhringer, H.; Rosati, P.; Schwope, A. +4 more
We report the discovery of a massive, X-ray-luminous cluster of galaxies at z=1.393, the most distant X-ray-selected cluster found to date. XMMU J2235.3-2557 was serendipitously detected as an extended X-ray source in an archival XMM-Newton observation of NGC 7314. VLT FORS2 R- and z-band snapshot imaging reveals an overdensity of red galaxies in …
Measuring the Three-dimensional Structure of Galaxy Clusters. I. Application to a Sample of 25 Clusters
Sereno, Mauro; Bautz, Mark W.; Longo, Giuseppe +1 more
We discuss a method to constrain the intrinsic shapes of galaxy clusters by combining X-ray and Sunyaev-Zel'dovich observations. The method is applied to a sample of 25 X-ray-selected clusters, with measured Sunyaev-Zel'dovich temperature decrements. The sample turns out to be slightly biased, with strongly elongated clusters preferentially aligne…
On the Polar Caps of the Three Musketeers
Caraveo, P. A.; Bignami, G. F.; Mereghetti, S. +2 more
XMM-Newton EPIC observations of PSR B0656+14, PSR B1055-52, and Geminga have substantially increased the collection of statistics available for these three isolated neutron stars, so apparently similar to deserve the nickname of the Three Musketeers, given to them by Becker & Trümper. Here we take advantage of the EPIC statistics to perform ph…
Coronal Evolution of the Sun in Time: High-Resolution X-Ray Spectroscopy of Solar Analogs with Different Ages
Skinner, Stephen L.; Güdel, Manuel; Ness, Jan-Uwe +3 more
We investigate the long-term evolution of X-ray coronae of solar analogs based on high-resolution X-ray spectroscopy and photometry with XMM-Newton. Six nearby main-sequence G stars with ages between ~0.1 and ~1.6 Gyr and rotation periods between ~1 and 12.4 days have been observed. We use the X-ray spectra to derive coronal element abundances of …
Probing the Environment in Gamma-Ray Bursts: The Case of an X-Ray Precursor, Afterglow Late Onset, and Wind Versus Constant Density Profile in GRB 011121 and GRB 011211
Piro, L.; Frontera, F.; Costa, E. +9 more
In this paper we present BeppoSAX and XMM-Newton observations of two long gamma-ray bursts (GRBs), the X-ray-rich event of 2001 December 11 (GRB 011211) and the hard and very bright event of 2001 November 21 (GRB 011121). In both events we find evidence of a late X-ray burst taking place several minutes after the prompt emission. In the November b…