Gamma Rays from the Distant BL Lac 1ES 0347-121
October 2007 The active galaxy 1ES 0347-121 was discovered as an X-ray source in the Einstein slew survey (Elvis et al. 1992) and was later classified as a BL Lac type object (Schachter et…
PKS 2155–304 – Photons from a Hotter Hell
September 2007 “Photons from a hotter hell” is the title of T. Weekes recent commentary in Nature, concerning the recent detection of giant outbursts of active galaxies observed in high-energy gamma rays. At the…
Confirming MGRO 1908+06
August 2007 Recently, the Milagro collaboration, operating a ground-based air shower detector based on the water Cherenkov technique, announced the detection of several new sources of very-high-energy gamma rays in the Galactic Plane (A.…
The Supernova Remnant RCW 86
July 2007 RCW 86 is a supernova remnant with a barrel-shaped shell, nicely visible in X-rays (top image), in the optical and in radio waves (Fig. 1). Concerning its age, two options are discussed…
PWN Abundance – HESS J1718–385
June 2007 Pulsar wind nebulae – PWNe – are amongst the most abundant sources of very high energy gamma rays in our Galaxy. Rotational energy of the neutron star is converted – by some…
HESS J1912+101 – Yet Another Pulsar Wind Nebula?
May 2007 The H.E.S.S. survey of the Galactic Plane (Aharonian et al. 2005, 2006) initially covered the range from –30 degr. to +30 degr. Galactic longitude. More recently, the survey region was extended to…
Gamma Rays from W28 – an Old Supernova Remnant and Molecular Clouds
April 2007 It is a long-held idea that supernova remnants are acceleration sites for nucleonic cosmic rays. Indeed supernova shells are clearly seen as sources of high energy gamma rays (SOM 2005/01, SOM 2005/03),…
HESS J1640–465 – A Pulsar Wind Nebula?
March 2007 The gamma-ray source HESS J1640-465 (Fig. 1) was discovered during the survey of the Galactic plane; with a size of 0.045 degrees it is among the most compact sources in the survey,…
A Point-Like Gamma-Ray Source in Monoceros
February 2007 Previous H.E.S.S. results on the supernova remnants RX J1713.7-3946 and RX J0852.0-4622 have clearly demonstrated that supernova shock fronts are capable of accelerating particles to very high energies. Gamma rays are produced…
HESS J1616-508 – Evidence for a Dark Particle Accelerator
January 2007 HESS J1616–508 (Fig. 1) is one of the objects discovered in the H.E.S.S. survey of the Galactic Plane; it is an extended source with a size of about 8 arc min., a…
