相关论文: High Energy Results from BeppoSAX
A soft X-ray excess has been claimed to exist in and around a number of galaxy clusters and this emission has been attributed to the warm-hot intergalactic medium that may constitute most of the baryons in the local universe. We have…
The soft X-ray excess emission in the southern cluster Sersic 159-03 represents hiterto the strongest effect of its kind. Emission in the ~0.2-0.4 keV passband is detected far in excess of the expected contribution from the hot phase of the…
We present a detailed X-ray study of the central subcluster of the nearby ($z$ $\sim$0.0368) Hercules cluster (Abell 2151) identified as A2151C that shows a bimodal structure. A bright clump of hot gas with X-ray emission extending to…
We report Chandra X-ray observations and optical weak-lensing measurements from Subaru/Suprime-Cam images of the double galaxy cluster Abell 2465 (z=0.245). The X-ray brightness data are fit to a beta-model to obtain the radial gas density…
We have selected seven medium-distant clusters of galaxies (z ~ 0.1 - 0.3) for multi-wavelength observations with the goal of investigating their dynamical state. Following Paper I (Pierre et al. 1999) which reported the ASCA results about…
Intriguing signals with excesses over expected backgrounds have been observed in many astrophysical and terrestrial settings, which could potentially have a dark matter origin. Astrophysical excesses include the Galactic Center GeV…
The masses of clusters of galaxies estimated by gravitational lensing exceed in many cases the mass estimates based on hydrostatic equilibrium. This may suggest the existence of nonthermal pressure. We ask if radio galaxies can heat and…
We submit that non thermalized support for the outer intracluster medium in relaxed galaxy clusters is provided by turbulence, driven by inflows of intergalactic gas across the virial accretion shocks. We expect this component to increase…
We propose a novel component to the understanding of the temperature structure of galaxy clusters which does not rely on any heating or cooling mechanism. The new ingredient is the use of non-extensive thermo-statistics which is based on…
Using archival Chandra data we studied the X-ray emission properties of PSR B2224+65 and its environment. Albeit limited by photon statistics the spectral analysis suggests that the bulk of the emission from PSR B2224+65 is non-thermal.…
Aims. We aim to characterize the gas properties in the cluster outskirts ($R_{500}<r<R_{200}$) and in the detected inter-cluster filaments ($>R_{200}$) of the A3391/95 system and to compare them to predictions. Methods. We performed X-ray…
We have derived azimuthally-averaged radial temperature profiles of the X-ray gas contained within 11 clusters of galaxies with redshift z=0.03-0.2 with BeppoSAX. Each of the 11 clusters have had their radial temperature profiles previously…
We present the analysis of 31 observations of 20 bright Compton thin Seyfert 2s, in the 0.1-200 keV band, performed with the BeppoSAX satellite. The sample consists of all Seyfert 2s in the BeppoSAX public archive, with a 2-10 keV flux…
An extremely soft X-ray excess throughout galaxy clusters has been claimed as a new feature of these sytems, with important physical implications. We have reexamined this feature in the five clusters for which it has been discussed, using…
The spectrum of the 0.1-7.0 keV cosmic X-ray background (CXB) at galactic latitudes >|25| degrees has been measured using the BeppoSAX Low-Energy Spectrometer Concentrator (LECS). Above 1 keV the spectrum is consistent with a power-law of…
We report an X-ray study of the composite supernova remnant G327.1-1.1, with particular emphasis on its thermal emission. By virtue of a combined spatial and spectral analysis, we have been able to model the X-ray emission of the remnant as…
Early X-ray observations suggested that the intracluster medium cools and condenses at the centers of clusters, leading to a cooling flow of plasma in the cluster core. The increased incidence of emission-line nebulosity, excess blue light,…
Some clusters of galaxies have been identified as powerful sources of non-thermal radiation, from the radio to X-ray wavelengths. The classical models proposed for the explanation of this radiation usually require large energy densities in…
We observed outer regions of a bright cluster of galaxies A2142 with Suzaku. Temperature and brightness structures were measured out to the virial radius ($r_{200}$) with good sensitivity. We confirmed the temperature drop from 9 keV around…
The detection of diffuse radio emission associated with clusters of galaxies indicates populations of relativistic leptons infusing the intracluster medium. Those electrons and positrons are either injected into and accelerated directly in…