KASCADE-Grande is an extensive air shower experiment array to study the cosmic ray primary composition and the hadronic interactions in the energy range E0=1016-1018eV.
The experiment is situated on site of the Forschungszentrum Karlsruhe. It measures simultaneously the electromagnetic, muonic and hadronic componenets of extensive air showers of cosmic rays.
As an extension of the former KASCADE experiment running successfully since 1996, KASCADE-Grande was built by reassembling 37 stations of the former EAS-TOP experiment -basically the electromagnetic detectors- running between 1987 and 2000 at Campo Imperatore, Grand Sasso Loboratories, Italy.
One of the main results obtained by these two experiments is a picture of increasingly heavier composition above the 'knee' caused by a break in the spectrum of the light components. Conventional acceleration models predict a change of the composition towards heavier components. The discovery of the knee in the heavy components, represented by iron, would be a convincing verification of these theories. From the observed rigidity dependent breaks of the spectra of different lighter primaries observed between 1014 and 1016eV, the iron 'knee' is expected around E0=1017eV.
The KASCADE-Grande Collaboration
The KASCADE-Grande Experiment
- A scintillator array measures the electrons, photons and muons outside the core region of extensive air showers in 252 detector stations on a rectangular grid of 13 m spacing, hence forming an array of 200 m x 200 m.
A 20 x 16 m2 iron stack arranged in 9 horizontal layers of 11 nuclear interaction length is equipped with 10808 ionisation chambers filled with Tetramethylsilane (TMS) or Tetramethylpentane (TMP) respectively working at room temperature. Each chamber has 4 readout electrodes, thus the energy release of hadrons is measured in more than 43000 electronic channels. Below 30 radiation length of absorber the central calorimeter contains a layer of 456 scintillation detectors acting as trigger for the calorimeter and measuring the arrival time of hadrons. Underneath the calorimeter two layers of multiwire proportional chambers measure muon tracks above an energy of 2 GeV with about 1.0° angular accuracy.
- A muon tracking detector is located north of the KASCADE-Grande central detector. In a 50 m long tunnel muons above an energy threshold of 0.8 GeV are measured with streamer tubes. On an active area of 128 m^2 muons are tracked with an accuracy of 0.5°.
- The KASCADE-Grande detector array has been realized by means of 37 stations at a mutual distance of about 130 m covering an area of 0.5 km^2 next to the KASCADE site in order to operate jointly with the KASCADE detector components. Each KASCADE-Grande array station is equipped with 10 m^2 of scintillation counters and the electronic components to generate a trigger signal and for calibration purposes. A central data acquisition station (DAQ) collects the data from all stations and generates a vaild experiment trigger.
- The KASCADE-piccolo trigger array consists of an array of 8 stations equipped with 10m^2 of plastic scintillator each and is placed towards the center of the Grande array. The main aim of piccolo is to provide an external trigger to Grande and to KASCADE for coincidence events.