LOPES (telescope)

LOPES was a digital radio antenna array for measuring air showers induced by cosmic rays. It was located at the North Campus of the Karlsruhe Institute of Technology, on the same site as the KASCADE-Grande experiment, and was dismantled in 2013 measuring mode after about 10 years.

Principle of measurement

When high-energy particles in cosmic rays hit the Earth's atmosphere, they form an extensive air shower of secondary particles. Among the offspring include many electrons and positrons, which are deflected by the Lorentz force in the magnetic field. The result is a radio pulse in the megahertz range, typically lasting a few nanoseconds and can be measured by experiments such as LOPES.

Whenever detect the particle detectors of KASCADE -Grande a high-energy air showers, LOPES additionally measures the radio signal in the frequency range from 40 MHz to 80 MHz. Then, the digitally recorded radio signal is further processed with computers and evaluated. The goal is to reconstruct as much information about the primary, which has the air showers and thus triggered the radio pulse. In particular, the direction of arrival, the power, and the mass of the primary particle to be estimated from an analysis of the measured radio signal.

History and organization

LOPES started in 2003, initially with 10 dipole antennas within the Kasade -Grande - point frame. For this prototype hardware of the LOFAR radio observatory would be used. Initial target of LOPES was to show that it possible to detect any cosmic rays with the digital radio metrology. Accordingly, the LOPES abbreviation for " LOFAR PrototypE station " is. Ever since the principal evidence is furnished, LOPES is the development of radio - measuring technology. Therefore, LOPES has been expanded several times and rebuilt. 2005 20 more dipole antennas were installed in 2010 and found a conversion instead of 10 Tripolantennen, each Tripolantenne consists of three crossed, perpendicular dipole antennas. Early 2013 LOPES was turned off and finally degraded in the summer of 2013.