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H.E.S.S. is an experiment for ground based GeV/TeV gamma ray astronomy of the new generation. It consists of four large Cherenkov telescopes operating in stereoscopic observation mode. Its construction in Namibia was completed at the end of 2003. Already during the installation phase, exciting results have been achieved, and after completion several discoveries have been made. Some of the results and discoveries are reported, such as the first image of a shell-type supernova remnant resolved at arc minute scale (RXJ 1713 – 3946), the discovery of the unique binary pulsar system PSR B1259 – 63 and of a yet-unidentified source in the same field of view (HESS J1303 – 631), and the observation of the galactic centre region. Amongst the extragalactic sources, the blazers Mkn 421 and PKS 2155 – 304 have also been detected.

Recent work has indicated that WIMP annihilation in stellar cores has the potential to contribute significantly to a star's total energy production. We report on progress in simulating the effects of WIMP capture and annihilation upon stellar structure and evolution near supermassive black holes, using the new DarkStars code. Preliminary results indicate that low-mass stars are the most influenced by WIMP annihilation, which could have consequences for upcoming observational programs.

In 2013 April a new magnetar, SGR1745−2900, was discovered as it entered an outburst, at an angular separation of only 2.4 arcsec from the supermassive black hole at the centre of the Milky Way, Sagittarius A*. The new source was detected both in the radio and X-ray bands, with a peak X-ray luminosity L_X ∼ 5 × 10³⁵ erg s⁻¹, and it has a spin-down magnetic field of ∼ 2 × 10¹⁴ G. Here we report on the long-term Chandra (twenty-six observations) and XMM–Newton (eight observations) X-ray monitoring campaign of SGR 1745−2900 from the onset of the outburst in 2013 April until 2014 September. This magnetar shows a slow flux decay compared to other magnetars and a rather inefficient surface cooling. Starquake-induced crustal cooling models alone have difficulty in explaining the high luminosity of the source for the first ∼200 d of its outburst. Additional heating of the star surface from currents flowing in a twisted magnetic bundle is probably playing an important role in the outburst evolution.

We announce the public release of the 'dark' stellar evolution code DarkStars. The code simultaneously solves the equations of WIMP capture and annihilation in a star with those of stellar evolution assuming approximate hydrostatic equilibrium. DarkStars includes the most extensive WIMP microphysics of any dark evolution code to date. The code employs detailed treatments of the capture process from a range of WIMP velocity distributions, as well as composite WIMP distribution and conductive energy transport schemes based on the WIMP mean-free path in the star. We give a brief description of the input physics and practical usage of the code, as well as examples of its application to dark stars at the Galactic centre.