C. Schultz

Status of the technologies for the production of the Cherenkov telescope array (CTA) mirrors

The Cherenkov Telescope Array (CTA) is the next generation very high-energy gamma-ray observatory, with at least 10 times higher sensitivity than current instruments. CTA will comprise several tens of Imaging Atmospheric Cherenkov Telescopes (IACTs) operated in array-mode and divided into three size classes: large, medium and small telescopes. The total reflective surface could be up to 10,000 m2 requiring unprecedented technological efforts. The properties of the reflector directly influence the telescope performance and thus constitute a fundamental ingredient to improve and maintain the sensitivity. The R&D status of lightweight, reliable and cost-effective mirror facets for the CTA telescope reflectors for the different classes of telescopes is reviewed in this paper.

The FSRQs 3c 279 and PKS 1510-089: Magic Latest Results and Multiwavelength Observations

At very high energy (VHE, E> 100 GeV), we count only three blazars of the flat spectrum radio quasars (FSRQs) type to date. The MAGIC experiment detected all three of them; here we present MAGIC observations of 3C 279 and PKS 1510-089. 3C 279 was observed in 2011, without a significant detection, hence upper limits on the differential flux have been computed. The MAGIC observations of PKS 1510-089 in 2012 were triggered by alerts of high activity states and resulted in a significant detection. MAGIC observations are complemented with simultaneous multiwavelength observations in high energy γ rays, X-rays, optical and radio wavelengths and polarization measurements. With the study of the spectral features and the variability observed, we aim to identify the physical processes responsible for the behavior of this source class. In particular, we propose coherent scenarios, which take into account both the modeling of the spectral energy distribution and the constraints obtained from the lightcurves.

Flat spectrum radio quasars: MAGIC results and unexpected features

The detection of Flat Spectrum Radio Quasars (FSRQs) in the Very High Energy (VHE, E>100 GeV) range is challenging, mainly because of their steep soft spectra. Often neither the emission nor the variability features of recently discovered VHE-FSRQs can be explained with the models developed so far for BL Lacs. Here we present the latest MAGIC results for all the three FSRQs known to be VHE emitters. We start with the 2010 discovery of PKS 1222+21 (z = 0.432), whose fast variability challenges simple one-zone emission models, requiring a more complicated scenario. Second, we present the latest results on 3C 279, the most distant AGN (z = 0.536) and first FSRQ detected in very high energies. It was observed in 2011, first during a monitoring campaign and later observations were triggered by a flare detected with Fermi-LAT. Finally, we report the 2012 detection of PKS 1510-089 (z = 0.36). This summary of VHE observations is the first step for a forthcoming study of multiwavelength spectral properties of thes...