Bonn 2010 – wissenschaftliches Programm
T 104.3: Gruppenbericht
Donnerstag, 18. März 2010, 17:20–17:40, HG XII
Detecting High Energy Cosmic Rays with LOFAR — •Andreas Horneffer — Dep. Astrophysics, Radboud University Nijmegen, The Netherlands
LOFAR, the Low Frequency Arrray is a new radio telescope for the frequency range of 10–250 MHz, that is being built in the Netherlands. It is the first so called ”digital radio telescope” that uses fields of simple antennas as sensing elements, digitizes the signal from each antenna, and does all further processing with digital computers. LOFAR can detect cosmic particles in two ways: by measuring radio pulses from air showers and by searching for radio pulses from particle similar cascades in the lunar regolith.
Designed primarily as a radio interferometer, LOFAR will have a core with a high density of radio antennas, which will be extremely well calibrated. This high sensitivity and excellent calibration will make LOFAR an unique tool to study the radio properties of single air showers and thus test and refine our theoretical understanding of the radio emission process. In addition it will be possible to form several independent tied array beams with the full LOFAR array to cover the moons surface. Searching for radio pulses originating from one spot on the lunar surface will give it unprecedented sensitivity to cosmic rays or neutrinos at energies around 1022 eV.
Triggering for both detection methods means detecting a radio pulse of some tens of nanoseconds width and discriminating real events from radio interference. Together this can only be done with a digital radio telescope, such as LOFAR.