arXiv subjects

Masahiro Teshima

Publications and source records attributed to Masahiro Teshima.

21 records · Page 2Linked to original sources

arXiv2007

Upgrade of the MAGIC Telescope with a Multiplexed Fiber-Optic 2 GSamples/s FADC Data Acquisition system

In February 2007 the MAGIC Air Cherenkov Telescope for gamma ray astronomy was fully upgraded with a fast 2 GSamples/s digitization system. The upgraded readout system uses a novel fiber-optic multiplexing technique. It consists of 10-bit 2 GSamples/s FADCs to digitize 16 channels consecutively and optical fibers to delay the analog signals. A distributed data acquisition system using GBit Ethernet and FiberChannel technology allows to read out the 100 kByte events with a continuous rate of up to 1 kHz.

astro-ph↗

arXiv2007

Discovery of Very High Energy Gamma-Rays from the Distant Flat Spectrum Radio Quasar 3C 279 with the MAGIC Telescope

The quasar 3C 279 is one of the best-studied flat spectrum radio quasars. It is located at a comparatively large redshift of z=0.536: E>100 GeV observations of such distant sources were until recently impossible both due to the expected steep energy spectrum and the expected attenuation of the gamma-rays by the extragalactic background light. Here we present results on the observation of 3C 279 with the MAGIC telescope in early 2006. We report the detection of a significant very high energy gamma-ray signal in the MAGIC energy range on the observation night of 2006 February 23.

astro-ph↗

arXiv2003

Signatures of Ultra-High Energy Cosmic Ray Composition from Propagation of Nuclei in Intergalactic Photon Fields

We present a calculation of nuclei propagation with energies above 1 EeV in the intergalactic photon field. The calculation is based on a Monte Carlo approach for the nucleus-photon interaction as well as the intergalactic magnetic field. We then assume that the Ultra-High Energy Cosmic Rays are nuclei which are emitted from extra-galactic point sources. Four bumps are found in the energy spectrum of the UHECR which form clusters in the distribution of their arrival directions. Based on this calculation, the energy distribution of the clustered events is discussed.

astro-ph↗