We present ROSAT PSPC observations of the nova-like, or intermediate polar, TT Ari and the eclipsing polar DP Leo. Observations of TT Ari were performed as part of a simultaneous mul-tiwavelength campaign. The X-ray spectrum from the ROSAT PSPC (0.2-2 keV) was combined with Ginga observations (2-37 keV) to suggest the presence of at least three distinct emission components: an optically thin pl...

We report results from the spectral analysis of pointed ROSAT PSPC observations of six PG quasars and the weak-bump quasar PHL 1657. Disregarding other frequency bands, the PSPC data are represented best by simple power-law source spectra (dN=dE / EΓ) with a slope Γ = 2:5 0:4 and do not show evidence for a more complex structure. However, within the limits given by statistics and systematical e...

The important human pathogen Streptococcus pneumoniae was found to absorb factor H, an inhibitor of complement, from human plasma. We identified the gene encoding a novel surface protein, factor H-binding inhibitor of complement (Hic), in the pspC locus of type 3 pneumococci. Unlike PspC proteins in other serotypes, Hic is anchored to the cell wall by means of an LPXTG motif, and the overall se...

The ROSATDeep Survey in the LockmanHole is the most sensitive X-ray survey performed to date, encompassing an exposure time of 207 ksec with the PSPC and a total of 1.32 Msec with the HRI aboard ROSAT. Here we present the complete catalogue of 50 X-ray sources with PSPC fluxes (0.5-2 keV) above 5.5 × 10−15 erg cm−2 s−1. The optical identifications are discussed in an accompanying paper (Schmidt...

Abstract Performing accurate and reliable dosimetry in spatially fractionated beams remains a significant challenge due to the steep dose gradients microscopic scale of features. This results many conventional detectors instrumentation being unsuitable for online dosimetry, necessitating frequent offline validation using radiochromic film. In this study, use Complementary Metal-Oxide-Semiconduc...

We investigate the X-ray properties of the Parkes sample of flat-spectrum radio sources using data from the ROSAT All–Sky Survey and archival pointed PSPC observations. In total, 163 of the 323 sources are detected. For the remaining 160 sources 2σ upper limits to the X-ray flux are derived. We present power-law photon indices in the 0.1–2.4 keV energy band for 115 sources, which were either de...

In previous works we have developed a method to convert solar X-ray data, collected with the Yohkoh/SXT, into templates of stellar coronal observations. Here we apply the method to several solar flares, for comparison with stellar X-ray flares. Eight flares, from weak (GOES class C5.8) to very intense ones (X9) are selected as representative of the flaring Sun. The emission measure distribution...