90 citations · 148 across the 6 of their papers we have counts for
6 papers
Stratospheric temperature anomalies as imprints from the dark Universe
K. Zioutas, A. Argiriou, H. Fischer +4
The manifestation of the dark Universe begun with unexpected large scale astronomical observations. Here we are investigating the origin of small scale anomalies, like that of the…
Short time-scale optical variability of the dwarf Seyfert nucleus in NGC 4395
J. E. Skelton, A. Lawrence, A. Pappa +2
We present optical spectroscopic observations of the least-luminous known Seyfert 1 galaxy, NGC 4395, which was monitored every half-hour over the course of 3 nights. The continuum…
The BeppoSAX spectrum of the composite galaxy Mrk609
A. Pappa, I. Georgantopoulos, M. Ward +1
We present Bepposax observations of the starburst/Seyfert composite galaxy Mrk609. This enigmatic object has an optical spectrum dominated by the features of starburst galaxies, ye…
ASCA observations of deep ROSAT fields V. The X-ray spectrum of hard X-ray selected QSOs
A. Pappa, G. C. Stewart, I. Georgantopoulos +3
We present an analysis of the \rosat and \asca spectra of 21 broad line AGN (QSOs) with detected in the 2-10 keV band with the \asca \gis. The summed spectrum in the \asc…
The X-ray spectra of optically selected Seyfert 2 galaxies. Are there any Sy2 galaxies with no absorption?
A. Pappa, I. Georgantopoulos, G. C. Stewart +1
We present an X-ray spectral analysis of a sample of 8 bona-fide Seyfert 2 galaxies, selected on the basis of their high flux, from the Ho et al. (1997) spectro…
X-ray observations of the Ultraluminous infrared galaxy IRAS19254-7245 (The Superantennae)
A. Pappa, I. Georgantopoulos, G. C. Stewart
We present ROSAT HRI and ASCA observations of the well known ULIRG IRAS19254-7245 (the Superantennae). The object is not detected by ROSAT yielding a 3σupper limit of L_x ~8x10^{41…