This paper reports that the X-ray spectrum from Galactic Center Emission (GCXE) is expressed by assembly of active binaries, non-magnetic Cataclysmic Variables, magnetic Variables (X-ray star: XAS), cold matter and diffuse sources. In fitting limited components XASs, GCXE exhibits significant excesses with $\chi^2/d.o.f. =5.67$. The are found at energies K$\alpha$, He$\alpha$, Ly$\alpha$ radiat...

On 4 July 2001, X–rays from Mars were detected for the first time. The observation was performed with the ACIS–I detector onboard Chandra and yielded data of high spatial and temporal resolution, together with spectral information. Mars is clearly detected as an almost fully illuminated disk, with an indication of limb brightening at the sunward side, accompanied by some fading on the opposite ...

The BeppoSAX archive is currently the largest reservoir of high sensitivity simultaneous soft and hard-X ray data of Seyfert galaxies. From this database all the Seyfert galaxies (105 objects of which 43 are type I and 62 are type II) with redshift lower than 0.1 have been selected and analyzed in a homogeneous way (Dadina 2007). Taking advantage of the broad-band coverage of the BeppoSAX MECS ...

X-ray emission by sparks implies bremsstrahlung from a population of energetic electrons, but the details of this process remain a mystery. We present detailed statistical analysis of X-ray spectra detected by multiple detectors during sparks produced by 1 MV negative high-voltage pulses with 1 μs risetime. With over 900 shots, we statistically analyze the signals, assuming that the distributio...

With the ASCA X-ray satellite, we perform spatial and spectral studies of the shell-type supernova remnant (SNR) γ Cygni that is associated with the brightest EGRET unidentified source 3EG J2020+4017. At energies below 3 keV the bulk of the X-ray flux from the remnant is well described by the emission of thermal plasma with characteristic temperature kTe ≃ 0.5–0.9 keV. In addition to this therm...

We investigate the nature of the luminous X-ray source population detected in a (72 ks) Chandra ACISS observation of NGC 4038/39, the Antennae galaxies. We derive the average X-ray spectral properties of sources in different luminosity ranges, and we correlate the X-ray positions with radio, IR, and optical (HST) data. The X-ray sources are predominantly associated with young stellar clusters, ...

The observation of a bright X-ray source by the Chandra X-ray Observatory's High Energy Transmission Grating Spectrometer (HETGS) can be compromised by photon pile-up in the CCD leading to false absorption features in the observed spectrum. A method for removing the e ects of pile-up in a dispersed grating spectrum is presented. The e ectiveness of the technique is demonstrated through its appl...

We report X-ray observations of the nearby, powerful radio galaxy Pictor A with the Chandra Observatory and optical and near uv observations of its western radio hot spot with the Hubble Space Telescope. X-ray emission is detected from the nucleus, a 1. ′ 9 (110 kpc) long jet to the west of the nucleus, the western radio hot spot some 4. ′ 2 (240 kpc) from the nucleus, and the eastern radio lob...