J. Wochele

The cosmic-ray experiment KASCADE

KASCADE has been designed to measure air showers of primary cosmic-ray energies in the PeV region and to investigate the knee phenomenon in the all-particle energy spectrum. Several observations are measured simultaneously for each event by different detector systems. The experiment started to take data in 1996 and has been completed and extended since then. The individual detector systems and their performances are described. Also, the experience in long-term operation of the experiment and the interplay between different components is outlined.

A WARM-LIQUID CALORIMETER FOR COSMIC-RAY HADRONS

Abstract An iron sampling calorimeter for cosmic-ray hadrons used in the centre of a large air shower experiment is described. The iron absorber is interspersed with eight layers of ionisation chambers filled with the room-temperature liquids tetramethylsilane and tetramethylpentane. Experiences gained from the calorimeter, its performance and long-term stability are presented. For energies in the TeV range shower profiles and transition curves have been measured and are compared with Monte Carlo calculations employing the FLUKA code. Good agreement has been found except in the lateral halo region. In the outer regions the energy deposition found is smaller than that obtained by the simulations.

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.

The KASCADE Experiment

A new extensive air shower (EAS) experiment has been installed at the laboratory site of the Forschungszentrum Karlsruhe. The main aim of the KASCADE [1] project is the determination of the chemical composition in the energy range around and above the knee of the primary cosmic ray spectrum. The main advantage of the new installation is the simultaneous measurement of a large number of observables for each individual event. This is achieved by the combination of various advanced detection techniques for the electromagnetic, the muonic, and the hadronic component of the extensive air showers. Data taking with a large part of the experiment has started at the end of 1995. The estimated accuracy of air shower data is discussed for the various detector components of KASCADE and first very preliminary results are presented.

Radar reflection off extensive air showers

We investigate the possibility of detecting extensive air showers by the radar technique. Considering a bistatic radar system and different shower geometries, we simulate reflection of radio waves off the static plasma produced by the shower in the air. Using the Thomson cross-section for radio wave reflection, we obtain the time evolution of the signal received by the antennas. The frequency upshift of the radar echo and the power received are studied to verify the feasibility of the radar detection technique.

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 Cosmic-ray Data Centre KCDC: granting open access to astroparticle physics research data

The ‘KASCADE Cosmic ray Data Centre’ is a web portal (https://kcdc.ikp.kit.edu), where the data of the astroparticle physics experiment KASCADE-Grande are made available for the interested public. The KASCADE experiment was a large-area detector for the measurement of high-energy cosmic rays via the detection of extensive air showers. The multi-detector installations KASCADE and its extension KASCADE-Grande stopped the active data acquisition in 2013 after more than 20 years of data taking. In several updates since our first release in 2013 with KCDC we provide the public measured and reconstructed parameters of more than 433 million air showers. In addition, KCDC provides meta data information and documentation to enable a user outside the community of experts to perform their own data analysis. Simulation data from three different high energy interaction models have been made available as well as a compilation of measured and published spectra from various experiments. In addition, detailed educational examples shall encourage high-school students and early stage researchers to learn about astroparticle physics, cosmic radiation as well as the handling of Big Data and about the sustainable and public provision of scientific data.

A new release of the KASCADE Cosmic Ray Data Centre (KCDC)

The KASCADE Cosmic Ray Data Centre (KCDC) is a web-based platform to provide scientific data for the general public. KASCADE and its extension KASCADE-Grande fully completed the data accumulation at the end of 2013 after more than 20 years of measurements. The main purpose of KCDC is to archive original data such as from KASCADE to offer long-term scientific data for the high-energy astroparticle physics community as well as for students and the interested public via a sophisticated web portal. Recently, a new version named NABOO was released, based on a completely new back-end database and software. In addition, the amount of data increased by factor 3 compared to the previous release. Data from the Grande detector array are now also available. In this contribution, the KCDC web portal and the data availability as well as future plans will be discussed.

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.