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We conducted multi wavelength campaign on SS433 in Sept. 2002 using X-ray, B, Infra-Red and radio telescopes. We observed variabilities on a time-scale of few minutes in all the wavelengths. We interpret them to be due to bullet-like features from the accretion disk. We also present X-ray properties as obtained by RXTE.
Results of simultaneous INTEGRAL and optical observations of galactic microquasar SS433 in May 2003 and INTEGRAL/RXTE observations in March 2004 are presented. Persistent precessional variability with a maximum to minimum uneclipsed hard X-ray flux r
We report the results of a multi-wavelength campaign on the blazar Mrk 421 during outburst. We observed four strong flares at X-ray energies that were not seen at other wavelengths (partially because of missing data). From the fastest rise in the X-r
The spectral energy distribution (SED) of high-frequency peaked BL Lac objects (HBL) is characterized by two peaks: one in the UV-X-ray and one in the GeV-TeV regime. An interesting object for analyzing these broadband characteristics is PKS 2005-489
In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting superm
This short paper reviews several recent key observations of the processes occurring in the lower atmosphere (chromosphere and photosphere) during flares. These are: evidence for compact and fragmentary structure in the flare chromosphere, the conditi