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We present the results of a long M87 monitoring campaign in very high energy $gamma$-rays with the MAGIC-I Cherenkov telescope. A total of 150 hours of data was gathered between 2005 and 2007. No flaring activity was found during that time. Nevertheless, we have found an apparently steady and weak signal at the level of $7sigma$. We present the spectrum between 100 GeV and 2 TeV, which is consistent with a simple power law with a spectral index $-2.21pm0.21$ and a flux normalization (at 300 GeV) of $5.4pm1.1 times 10^{-8} frac{1}{mathrm{TeV s m}^{2}}$. It complements well with the previously published Fermi spectrum, covering an energy range of four orders of magnitude without apparent change in the spectral index.
We present the results of a long M87 monitoring campaign in very high energy $gamma$-rays with the MAGIC-I Cherenkov telescope. We aim to model the persistent non-thermal jet emission by monitoring and characterizing the very high energy $gamma$-ray
M87 is one of the closest (z=0.00436) extragalactic sources emitting at very-high-energies (VHE, E > 100 GeV). The aim of this work is to locate the region of the VHE gamma-ray emission and to describe the observed broadband spectral energy distribut
Context. 3C 279, the first quasar discovered to emit VHE gamma-rays by the MAGIC telescope in 2006, was reobserved by MAGIC in January 2007 during a major optical flare and from December 2008 to April 2009 following an alert from the Fermi space tele
We present LOFAR observations at 150 MHz of the borderline FRI/FRII giant radio galaxy NGC 6251. This paper presents the most sensitive and highest-resolution images of NGC 6251 at these frequencies to date, revealing for the first time a low-surface
We present new Giant Metrewave Radio Telescope observations at 235 MHz and 610 MHz of 18 X-ray bright galaxy groups. These observations are part of an extended project, presented here and in future papers, which combines low-frequency radio and X-ray