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Abstract: The KASCADE–Grande experiment, located at Karlsruhe Institute of Technology (Germany) is a multi-component extensive air-shower experiment devoted to the study of cosmic rays and their interactions at primary energies 1014–1018 eV. Main goals of the experiment are the measurement of the all-particle energy spectrum and mass composition in the 1016–1018 eV range by sampling charged (N ch ) and muon () components of the air shower. The method to derive the energy spectrum and its uncertainties, as well as the implications of the obtained result, is discussed. An overview of the analyses performed by KASCADE–Grande to derive the mass composition of the measured high-energy comic rays is presented as well. [Copyright &y& Elsevier]

The LOPES experiment (LOfar Prototype Station) has been built at the KASCADE-Grande experiment in order to test the LOFAR (LOw Frequency ARray) technology and demonstrate its capability for radio measurements in Extensive Air Showers (EAS). After the first positive results in the framework of the KASCADE-Grande experiment we developed the next generation of antennas, electronics, and trigger. The main new features are easy calibration of antennas with precise detection of polarization, and good capability of self-triggering. The results from this new design are under test in Karlsruhe. Furthermore the background situation was measured and analyzed. [ABSTRACT FROM AUTHOR]

We present the design and first test results of a new flash analog-to-digital-converters (FADCs)-based data acquisition (DAQ) system for the Grande array of the KAS- CADE-Grande experiment. The original KASCADE experiment at the Forschungszentrum Karlsruhe, Germany, has been extended by 37 detector stations of the former EAS-TOP experiment (Grande array) to provide sensitivity to energies of primary particles from the cosmos of up to 1018 eV. The new FADC-based DAQ system will improve the quality of the data taken by the Grande array by digitizing the scintillator signals with a 250-MHz sampling rate. The signals of each of the 37 detector stations are continuously recorded using interleaved 12-bit FADCs located on custom-made digitizer boards at each station. The digitizer boards feature a self-triggering mechanism, initiating the data transmission to the Grande DAQ station using programmable thresholds, a timestamp mechanism, and optical data transmission. The control logic is implemented using field progammable gate arrays (FPGAs). Five optical receiver and temporary storage modules receive the data from up to eight stations each (at an approximate rate of 2.5 MB/s per station) and transfer them into the memory of one of five PCs via a customized PCI interface card. Running on a master PC, the data acquisition software searches for coincidences in the timestamps, incorporates triggers generated by the other KASCADE-Grande components, and builds air shower events from the data of the individual stations. Completed Grande events are sent to the central DAQ of KASCADE-Grande at an approximate rate of a few air shower events per second. Two Grande stations have been equipped with the FADC-based data acquisition system, and first data are shown. [ABSTRACT FROM AUTHOR]

Abstract: The antenna array LOPES is set up at the location of the KASCADE-Grande extensive air shower experiment in Karlsruhe, Germany and aims to measure and investigate radio pulses from extensive air showers. The coincident measurements allow us to reconstruct the electric field strength at observation level in dependence of general EAS parameters. In the present work, the lateral distribution of the radio signal in air showers is studied in detail. It is found that the lateral distributions of the electric field strengths in individual EAS can be described by an exponential function. For about 20% of the events a flattening towards the shower axis is observed, preferentially for showers with large inclination angle. The estimated scale parameters , describing the slope of the lateral profiles range between 100 and 200m. No evidence for a direct correlation of with shower parameters like azimuth angle, geomagnetic angle, or primary energy can be found. This indicates that the lateral profile is an intrinsic property of the radio emission during the shower development which makes the radio detection technique suitable for large scale applications. [Copyright &y& Elsevier]

Abstract: When ultra high energy cosmic rays hit the atmosphere, they produce a shower of millions of secondary particles. Thereby the charged particles in the shower emit a radio pulse whilst deflected in the Earth''s magnetic field. LOPES is a digital antenna array measuring these radio pulses in the frequency range from 40 to 80MHz. It is located at the site of and triggered by the air shower experiment KASCADE-Grande at Karlsruhe Institute of Technology (KIT), Germany. In its present configuration, it consists of 15 east–west-polarized and 15 north–south-polarized, absolutely calibrated short dipole antennas, as well as 10 LPDAs (with two channels each). Furthermore, it serves as a test bench for technological developments, like new antenna types or a radio-based self-triggering (). To achieve a good angular reconstruction and to digitally form a beam into the arrival direction of the shower, it has a precise time calibration. [Copyright &y& Elsevier]

Abstract: KASCADE-Grande is a multi-detector experiment at KIT (Karlsruhe Institute of Technology) in Germany for measuring extensive air showers in the primary energy range of 100TeV to 1EeV. This paper does not provide a synopsis of all results of the KASCADE-Grande experiment. Rather it is focused on three aspects of current interests illustrating the advantages of a multi-detector facility. Results on the analysis of individual energy spectra of primary mass groups around the knee obtained by unfolding the shower size measurements of KASCADE with the help of the new hadronic interaction model EPOS and the all-particle energy spectrum at higher energies obtained by Grande measurements will be discussed. As KASCADE-Grande serves also as host of the LOPES radio detection experiment where both experiments measure the same showers, special emphasis will be given in comparing the characteristics and feasibility of both techniques in estimating the main parameters of high-energy primary cosmic rays: energy, composition, and arrival direction. [Copyright &y& Elsevier]

Abstract: We report in this paper on an analysis of 20 months of data taken with LOPES. LOPES is radio antenna array set-up in coincidence with the Grande array, both located at the Karlsruhe Institute of Technology, Germany. The data used in this analysis were taken with an antenna configuration composed of 30 inverted V-shape dipole antennas. We have restricted the analysis to a special selection of inclined showers—with zenith angle . These inclined showers are of particular interest because they are the events with the largest geomagnetic angles and are therefore suitable to test emission models based on geomagnetic effects.The reconstruction procedure of the emitted radio signal in EAS uses as one ingredient the frequency-dependent antenna gain pattern which is obtained from simulations. Effects of the applied antenna model in the calibration procedure of LOPES are studied. In particular, we have focused on one component of the antenna, a metal pedestal, which generates a resonance effect, a peak in the amplification pattern where it is the most affecting high zenith angles, i.e. inclined showers. In addition, polarization characteristics of inclined showers were studied in detail and compared with the features of more vertical showers for the two cases of antenna models, with and without the pedestal. [Copyright &y& Elsevier]

Abstract: LOPES is a radio antenna array co-located with the Karlsruhe Shower Core and Array DEtector, KASCADE–Grande in Forschungszentrum Karlsruhe, Germany, which provides well-calibrated trigger information and air shower parameters for primary energies up to . By the end of 2006, the radio antennas were re-configured to perform polarization measurements of the radio signal of cosmic ray air showers, recording in the same time both, the East–West and North–South polarization directions of the radio emission. The main goal of these measurements is to reconstruct the polarization characteristics of the emitted signal. This will allow a detailed comparison with theoretical predictions. The current status of these measurements is reported here. [Copyright &y& Elsevier]

Abstract: LOPES is set up at the location of the KASCADE-Grande extensive air shower experiment in Karlsruhe, Germany and aims to measure and investigate radio pulses from extensive air showers. Since radio waves suffer very little attenuation, radio measurements allow the detection of very distant or highly inclined showers. These waves can be recorded day and night, and provide a bolometric measure of the leptonic shower component. LOPES is designed as a digital radio interferometer using high bandwidths and fast data processing and profits from the reconstructed air shower observables of KASCADE-Grande. The LOPES antennas are absolutely amplitude calibrated allowing to reconstruct the electric field strength which can be compared with predictions from detailed Monte-Carlo simulations. We report about the analysis of correlations present in the radio signals measured by the LOPES 30 antenna array. Additionally, LOPES operates antennas of a different type (LOPES) which are optimized for an application at the Pierre Auger Observatory. Status, recent results of the data analysis and further perspectives of LOPES and the possible large scale application of this new detection technique are discussed. [Copyright &y& Elsevier]