6 papers · 1 filter
Saving Astronomical Treasures
Noah Brosch, Rene Hudec, Peter Kroll +1
The time domain is under-exploited in an astrophysical context, because the large photographic plate collections are almost never consulted by young astronomers. This is a result o…
High spectral and time resolution observations of the eclipsing polar RX J0719.2+6557
G. H. Tovmassian, P. Szkody, J. Greiner +7
We present phase-resolved spectral and multicolor CCD-photometric observations of the eclipsing polar RX J0719.2+6557 obtained with relatively high time (~600 sec/15 sec) and spect…
S 10943 Vulpeculae: A New ROSAT Selected Dwarf Nova, probably of SU Ursae Majoris Subclass
G. A. Richter, J. Greiner, P. Kroll
We have identified the ROSAT all-sky survey source RX J1953.1+2115 with a newly discovered dwarf novae (named S 10943 Vulpeculae) with a recurrence time of 83.6 days. With the expe…
A New Cataclysmic Variable RX J0757.0+6306: Candidate for the Shortest Period Intermediate Polar
G. H. Tovmassian, J. Greiner, P. Kroll +8
A new cataclysmic variable is identified as the optical counterpart of the faint and hard X-ray source RX J0757.0+6306 discovered during the ROSAT all-sky survey. Strong double-pea…
RX J0719.2+6557: A New Eclipsing Polar
G. Tovmassian, J. Greiner, F. -J. Zickgraf +4
A new magnetic, eclipsing cataclysmic variable is identified as the counterpart of the X-ray source RX J0719.2+6557 detected during the ROSAT all-sky survey. The relative phasing o…
Four new active galaxies with steep soft X-ray spectra
J. Greiner, R. Danner, N. Bade +3
We have discovered four AGN in the ROSAT all-sky-survey data with very steep X-ray spectra. We apply several models to these X-ray spectra with emphasis on warm absorber models whi…