W.D. Apel

Test of high-energy interaction models using the hadronic core of EAS

Using the large hadron calorimeter of the KASCADE experiment, hadronic cores of extensive air showers have been studied. The hadron lateral and energy distributions have been investigated in order to study the reliability of the shower simulation program CORSIKA with respect to particle transport, decays, treatment of low-energy particles, etc. A good description of the data has been found at large distances from the shower core for several interaction models. The inner part of the hadron distribution, on the other hand, reveals pronounced differences among interaction models. Several hadronic observables are compared with CORSIKA simulations using the QGSJET, VENUS and SIBYLL models. QGSJET reproduces the hadronic distributions best. At the highest energy, in the 10 PeV region, however, none of these models can describe the experimental data satisfactorily. The expected number of hadrons in a shower is too large compared with the observed number, when the data are classified according to the muonic shower size.

Test of interaction models up to 40 PeV by studying hadronic cores of EAS

The interpretation of extensive air shower measurements often requires a comparison with shower simulations in the atmosphere. These calculations rely on hadronic interaction models which have to extrapolate into kinematical and energy regions not explored by present-day collider experiments. The KASCADE experiment with its large hadron calorimeter and the detector array for the electromagnetic and muonic components provides experimental data to check such interaction models. For the simulations the program CORSIKA is used, which has several hadronic event generators embedded. For high-energy interactions (E_{rm{lab}}gtrsim100 {rm{GeV}}) the models DPMJET, {sc NEX{sc US}} , QGSJET and SIBYLL have been used. Low-energy interactions have been treated by GHEISHA and FLUKA. Different hadronic observables are investigated as well as their correlations with the electromagnetic and muonic shower components up to primary energies of about 40 PeV. Although the predictions of the more recent models are to a large extent compatible with the measured data within the range given by proton and iron primary particles, there are still significant differences between the individual models.

The KASCADE‐Grande Experiment

KASCADE-Grande is the enlargement of the KASCADE extensive air shower detector, realized to expand the cosmic ray studies from the previous 10–10 eV primary energy range to 10 eV. This is performed by extending the area covered by the KASCADE electromagnetic array from 200 200 to 700 700 m by means of 37 scintillator detector stations of 10 m area each. This new array is named Grande and provides measurements of the all-charged particle component of extensive air showers (Nch), while the original KASCADE array particularly provides information on the muon content ðNmÞ. Additional dense compact detector set-ups being sensitive to energetic hadrons and muons are used for data consistency checks and calibration purposes. The performance of the Grande array and its integration into the entire experimental complex is discussed. It is demonstrated that the overall observable resolutions are adequate to meet the physical requirements of the measurements, i.e. primary energy spectrum and elemental composition studies in the primary cosmic ray energy range of 10–10 eV. & 2010 Elsevier B.V. All rights reserved.

The KASCADE-grande experiment

KASCADE-Grande is an extensive air shower array co-located with the original KASCADE air shower experiment at Forschungszentrum Karlsruhe, Germany. The multi-detector system allows to investigate the energy spectrum, composition, and anisotropies of cosmic rays in the energy range extended up to 1018 eV. An overview on the performance of the apparatus and first results are presented.