Related papers: An ASCA Study of the W51 Complex

We present a detailed analysis of broad band X-ray data of the Seyfert 2 galaxy NGC5506. 2-10 keV band are detected during a 1-day ASCA observation, while no significant change in the 2-10 keV continuum shape is found. The ASCA spectrum…

We report the results of the analysis of ASCA/ROSAT observations of the compact luminous X-ray source found at the edge of the nearby star-forming dwarf galaxy Holmberg II (UGC 4305).Our ASCA spectrum revealed that the X-ray emission…

We present the results of ASCA observations of a heterogenous sample of 15 spiral galaxies. 8 are LINERs or low-luminosity AGN (LLAGN), 5 are starburst galaxies and 2 are normal spiral galaxies. We find that in all cases the ASCA spectra…

We present the results of an ASCA observation of the low-luminosity Seyfert 1.5 galaxy NGC 5033. A point-like X-ray source with a luminosity of 2.3x10^{41} erg s^{-1} in the 2--10 keV band (at 18.7 Mpc; Tully 1988, AAA045.002.054) was…

We report observation results of the super-soft X-ray sources (SSS) CAL87 and RXJ0925.7-4758 with the X-ray CCD cameras (Solid-state Imaging Spectrometer; SIS) on-board the ASCA satellite. We have applied theoretical spectral models to…

We have reanalysed the ASCA X-ray spectrum of the bright symbiotic star CH Cyg, which exhibits apparently distinct hard and soft X-ray components. Our analysis demonstrates that the soft X-ray emission can be interpreted as scattering of…

We present a catalogue of 107 point-like X-ray sources derived from a systematic analysis of all the ROSAT PSPC observations of the galactic center region performed in 1992-1993. Besides SgrA*, the massive black hole at the galactic center,…

Chandra ACIS-I data of the molecular cloud and HII region complex NGC 6334 were analyzed. The hard X-ray clumps detected with ASCA (Sekimoto et al. 2000) were resolved into 792 point sources. After removing the point sources, an extended…

We present the analysis of archival data from the Advanced Satellite for Cosmology and Astrophysics} (ASCA) of the supernova remnant (SNR) G39.2-0.3. G39.2-0.3 has been sometimes characterized as a shell-like remnant in the literature but…

We present an analysis of a recent XMM-Newton observation of Sgr A East, a supernova remnant located close to the Galactic Centre. Very high quality X-ray spectra reveal many emission lines from highly ionized atoms consistent with a…

We present evidence for shock acceleration of cosmic rays to high energies (about 10 TeV) in the supernova remnant IC 443. X-ray imaging spectroscopy with ASCA reveals two regions of particularly hard emission: an unresolved source embedded…

X-ray spectra of groups of galaxies, obtained with the GIS instrument onboard ASCA, were investigated for diffuse hard X-rays in excess of the soft thermal emission from their inter-galactic medium (IGM). In total, 18 objects with the IGM…

We present the results of the first imaging X-ray observations in the 0.4-10.0 keV bandpass of the nearby starburst galaxies M82 and NGC 253. The ASCA spectra of both M82 and NGC 253 are complex with strong line emission from O, Ne, Fe, Mg,…

The question of the origin of the hard X-ray/soft gamma-ray emission in Centaurus A (Cen A) persists despite decades of observations. Results from X-ray instruments suggest a jet origin since the implied electron temperature (kT_e) would…

We report results from simultaneous ASCA and RXTE observations of Cyg X-1 when the source made a rare transition from the hard (= low) state to the soft (= high) state in 1996. These observations together cover a broad energy range ~0.7--50…

The results from an X-ray spectral analysis of a large sample of quasars, observed with ASCA, are presented. Data reduction leaves 62 quasars, 35 radio-loud and 27 radio-quiet, suitable for spectral analysis. Differences are found between…

We present an ASCA discovery of diffuse hard X-ray emission from the Sgr C complex with its peak in the vicinity of the molecular cloud core. The X-ray spectrum is characterized by a strong 6.4-keV line and large absorption. These…

W51 is a giant radio complex lying along the tangent to the Sagitarius arm at a distance of about 7kpc from Sun, with an extension of about 1deg in the sky. It is divided into three components A,B,C where W51A and W51B consist of many…

We present the first results of the hard (5-10 keV) ASCA GIS survey SHEEP (Search for the High Energy Extragalactic Population). We have analysed 149 fields covering an area of 39 sq. deg detecting 69 sources. Several of these appear to be…

We observed a nearby merger remnant NGC 7252 with the X-ray satellite ASCA, and detected X-ray emission with the X-ray flux of (1.8+/-0.3)E-13 ergs/s/cm/cm in the 0.5 - 10 keV band. This corresponds to the X-ray luminosity of 8.1E40 ergs/s.…