Following the detection of strong TeV γ-ray flares from the BL Lac object 1ES 1959+650 with the Whipple 10 m Cherenkov telescope on May 16 and 17, 2002, we performed intensive Target of Opportunity (ToO) radio, optical, X-ray and TeV γ-ray observations from May 18, 2002 to August 14, 2002. Observations with the X-ray telescope RXTE (Rossi X-ray Timing Explorer) and the Whipple and HEGRA (High E...

The indirect detection of dark matter requires that dark matter annihilation products be discriminated from conventional astrophysical backgrounds. Here, we re-analyze GeV-band gamma-ray observations of the prominent Milky Way dwarf satellite galaxy Segue 1, for which the expected astrophysical background is minimal. We explicitly account for the angular extent of the conservatively expected ga...

We present the first X-ray detection of the Cartwheel’s ring. The impact that created the characteristic optical structure is responsible also for an enhanced level of star formation to which we can ascribe the relatively high level of X-ray emission observed. Deeper images and spectroscopic information are needed to confirm or disprove the hypothesis that High Mass X-ray Binaries contribute mo...