6 papers · 1 filter
Ultraluminous IRAS galaxy 10026+4347
X. -Y. Xia, Shude Mao, H. Wu +4
We study optical and X-ray properties of the ultraluminous IRAS galaxy 10026+4347. This galaxy is a narrow-line QSO with very strong FeII emission. Three optical spectra were taken…
AGN/galaxy separation in the ROSAT Bright Survey
I. Lehmann, G. Hasinger, A. D. Schwope +1
The X-ray luminosity function (XLF) of galaxies is dominated by AGN (classified by their optical spectra) above Lx=10**42 erg/s, below this value by normal galaxies. The X-ray flux…
Properties of new X-ray selected AGN
K. Bischoff, W. Pietsch, T. Boller +3
We present the results of a program to identify so far unknown active nuclei (AGN) in galaxies. Candidate galactic nuclei have been selected for optical spectroscopy from a cross-c…
Ultrasoft Narrow-Line Seyfert 1 galaxies: What physical parameter ultimately drives the structure and kinematics of their Broad Line Regions?
W. N. Brandt, Th. Boller
Recent X-ray observations have advanced the study of ultrasoft Narrow-Line Seyfert 1 galaxies and have revealed strikingly clear correlations between optical emission line properti…
High resolution imaging of the X-ray afterglow of GRB970228 with ROSAT
F. Frontera, J. Greiner, L. A. Antonelli +6
We report results of a ROSAT High-Resolution Imager (HRI) observation of the X-ray error box given by the BeppoSAX Wide Field Camera for the gamma-ray burst that occurred on 1997 F…
New active galactic nuclei detected in ROSAT All Sky Survey galaxies; Part I: Verification of selection strategy
W. Pietsch, Th. Boller, S. Doebereiner +3
We present the first results of a program to identify so far unknown active nuclei (AGN) in galaxies. Candidate galactic nuclei have been selected for optical spectroscopy from a c…