7 papers
Search for fast correlated X-ray and optical variability in Cir X-1 and XTE J1746-321
H. C. Spruit, H. Steinle, G. Kanbach
Coordinated observations X-ray+optical observations of two southern X-ray binaries, the black hole candidate XTE J1746-321 and the neutron star accreter Cir X-1 (a `microquasar') a…
A bright X-ray transient towards NGC 5128 (Centaurus A)
H. Steinle, K. Dennerl, J. Englhauser
During five ROSAT HRI observations in July 1995, a bright X-ray source (designated 1RXH J132519.8-430312) was detected 2.5' south-west of the nucleus of NGC 5128 (Centaurus A) at t…
A large high-energy gamma-ray flare from the blazar 3C 273
W. Collmar, O. Reimer, K. Bennett +8
The Compton Gamma-Ray Observatory (CGRO) experiments EGRET and COMPTEL observed the Virgo sky region continuously for 7 weeks between December 10, 1996 and January 28, 1997. The pr…
COMPTEL MeV Observations of the TeV Sources Markarian 421 and Markarian 501
W. Collmar, K. Bennett, H. Bloemen +5
The COMPTEL experiment aboard the COMPTON Gamma-Ray Observatory (CGRO) has observed the prominent TeV-blazars Mkn 421 and Mkn 501 many times between the start of its mission in Apr…
COMPTEL Observations of AGN at MeV-Energies
W. Collmar, K. Bennett, H. Bloemen +9
The COMPTEL experiment aboard CGRO, exploring the previously unknown sky at MeV-energies, has so far detected 10 Active Galactic Nuclei (AGN): 9 blazars and the radio galaxy Centau…
COMPTEL observations of the quasar PKS 0528+134 during the first 3.5 years of the CGRO mission
W. Collmar, K. Bennett, H. Bloemen +9
The COMPTEL observations of the blazar-type quasar PKS 0528+134 in the energy range 0.75 MeV to 30 MeV carried out between April 1991 and September 1994 have been analyzed. During…