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The nature of ultrahigh-energy cosmic rays (UHECRs) at energies >10(20) eV remains a mystery. They are likely to be of extragalactic origin, but should be absorbed within approximately 50 Mpc through interactions with the cosmic microwave background. As there are no sufficiently powerful accelerators within this distance from the Galaxy, explanations for(More)
Radio pulses emitted in the atmosphere during the air shower development of high-energy primary cosmic rays were measured during the late 1960ies in the frequency range from 2 MHz to 520 MHz. Mainly due to difficulties with radio interference these measurements ceased in the late 1970ies. LOFAR (Low Frequency Array) is a new digital radio interferometer(More)
KASCADE-Grande is the extension of the multi-detector setup KASCADE to cover a primary cosmic ray energy range from 100 TeV to 1 EeV. The enlarged EAS experiment provides comprehensive observations of cosmic rays in the energy region around the knee. Grande is an array of 700 x 700 m 2 equipped with 37 plastic scintillator stations sensitive to measure(More)
The first total syntheses of (+/-)-didehydrostemofoline (1) and (+/-)-isodidehydrostemofoline (3) are reported. The synthesis begins with the Diels-Alder reaction of readily available pyrrole 9 and ethyl (E)-3-nitroacrylate, the latter serving as a regioinverted equivalent of ketene. After hydrogenation to prevent retro-Diels-Alder reaction, the major(More)
The KASCADE-Grande experiment consists of a large scintillator array for the detection of charged particles from extensive air showers in the primary energy range ! # " % $ & ') (eV. In combination with the KASCADE muon detectors it provides the means to investigate the possible existence of an iron knee and the change in composition due to extragalactic(More)
KASCADE-Grande is a multi detector setup for the investigation of extensive air showers in the primary energy range of the knee including energies around the so-called second knee. With the data of the 700 · 700 m 2 large Grande array shower core position, shower direction, and the total number of electrons are reconstructed for events with primary energy(More)
Recent results from the KASCADE experiment on measurements of cosmic rays in the energy range of the knee are presented. Emphasis is placed on energy spectra of individual mass groups as obtained from sophisticated unfolding procedures applied to the reconstructed electron and truncated muon numbers of EAS. The data show a knee-like structure in the energy(More)
Recent results from the multi-detector setup KASCADE on measurements of cosmic rays in the energy range of the so called " first " knee (at ≈ 3 PeV) indicate a distinct knee in the energy spectra of light primary cosmic rays and an increasing dominance of heavy ones towards higher energies. This leads to the expectation of knee-like features of the heavy(More)
LOPES is set up at the location of the KASCADE-Grande extensive air shower experiment in Karlsruhe, Germany and aims to investigate radio pulses from extensive air showers experimentally and theoretically. Data taken during half a year of operation of 10 LOPES antennas (LOPES-10), triggered by EAS observed with KASCADE-Grande have been analysed. We report(More)