Mathieu de Naurois (CNRS)
After nearly a decade of operation, the three major arrays of atmospheric Cherenkov telescopes have revolutionized our view of the Very High Energy Universe, unveiling more than 100 sources of various types. MAGIC, consisting of two 17m diameter telescopes on the Canary island of La Palma, and VERITAS, with four 12m telescopes installed in southern Arizona, USA, largely explored the extragalactic sky, where the majority of the sources are active galactic nuclei (AGN), with gamma-ray emission originating in their relativistic jets. In July 2014 MAGIC discovered the most distant gamma-ray source at very high energies, the gravitationally lensed blazar S3 0218 residing at the redshift of 0.944. The FSRQ PKS 1441+25 (z=0.939), observed by MAGIC & VERITAS in 2015, showed a strong flaring activity over a time span of several weeks. Rapid variability from various BL Lacertae objects, down to minute timescales, has been observed by the three experiments, and measurement of their high-energy spectra allows the level of extragalactic background light to be constrained. Since the commissioning of the fifth, large telescope in December 2012, H.E.S.S. II is the only hybrid array of Imaging Atmospheric Cherenkov Telescopes operating in the energy range ~ 20 GeV to 100 TeV. With its broad energy range, H.E.S.S. explored the Galactic Plane with unprecedented sensitivity. The legacy release of the H.E.S.S. Galactic Plane Survey, consisting of 2800 hours of observations of the Galactic disk, reveals major new results. This is the first high-resolution (~0.1 deg) and sensitive (~2% Crab Nebula point-source sensitivity) survey of the Milky Way in TeV gamma rays. The Milky Way harbors a large variety of high energy sources of various types. In recent years, deep observations of several key Galactic regions of utmost importance for this field have been conducted by the three experiments. Among them are the Galactic Center region and its halo (particularly relevant for dark matter searches), the Cygnus region and its mysterious Milagro sources, the Crab Nebula and pulsar (surprisingly showing pulsed emission till above 1 TeV), the iconic gamma-ray supernova remnant RX J1713.7-3946 and other SNRs (Tycho, ...), the Vela pulsar and several binary systems such as LS 5039, PSR B1259-63, HESS J0632+057 and LSI 61 +303. Joint observations on several of these objects proved to be the most efficient way to understand their nature. A deep observation of the Large Magellanic Cloud revealed, for the first time, spectacular and powerful accelerators of stellar origin outside our own galaxy. Highlights of these observations with H.E.S.S. , MAGIC and VERITAS will be presented and discussed at the conference.
|Registration number following "ICRC2015-I/"||323|
Mathieu de Naurois (CNRS)