Search

The constant intensity cut method is a very useful tool to reconstruct the cosmic ray energy spectrum in order to combine or compare extensive air shower data measured for different attenuation depths independently of the MC model. In this contribution the method is used to explore the muon data of the KASCADE-Grande experiment. In particular, with this technique, the measured muon number spectra for different zenith angle ranges are compared and summed up to obtain a single muon spectrum for the measured showers. Preliminary results are presented, along with estimations of the systematic uncertainties associated with the analysis technique.

Using the muon facilities of the KASCADE central detector, the time structure of the EAS muon component is studied for core distances up to 130 m for primary energies of the knee region. Results are presented for the distributions of various moments and the dispersion of the arrival times relative to the arrival of the foremost muon, respectively. For the muon observations at larger core distances particular studies could be performed with the question to which extent EAS muon arrival time distributions display features with information about the energy and mass composition of the primary cosmic rays.

The KASCADE experiment measures extensive air showers induced by cosmic rays in the energy range around the so-called knee. The data of KASCADE have been used in a composition analysis showing the knee at 3-5 PeV to be caused by a steepening in the light-element spectra. Since the applied unfolding analysis depends crucially on simulations of air showers, different high energy hadronic interaction models (QGSJet and SIBYLL) were used. The results have shown a strong dependence of the relative abundance of the individual mass groups on the underlying model. In this update of the analysis we apply the unfolding method with a different low energy interaction model (FLUKA instead of GHEISHA) in the simulations. While the resulting individual mass group spectra do not change significantly, the overall description of the measured data improves by using the FLUKA model. In addition data in a larger range of zenith angle are analysed. The new results are completely consistent, i.e. there is no hint to any severe problem in applying the unfolding analysis method to KASCADE data., accepted for publication in Astroparticle Physics

Cosmic rays are energetic particles from outside the earth’s atmosphere. When a high energy cosmic ray hits the atmosphere it triggers a cascade of secondary particles produced in nuclear interactions, an air shower. Up to now the established methods of measuring air showers are detection of the particles that reach the ground level or optical observation of the Cherenkov or fluorescent light.

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 about the results of correlations with shower parameters present in the radio signals measured by LOPES-10. The extended setup LOPES-30 consists of 30 antennas which have an absolute calibration and the data of which will be compared with expectations from detailed Monte-Carlo simulations. In addition, LOPES operates antennas of a different type (LOPES STAR ) which are optimized for an application at the Pierre Auger Observatory.

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 m2 large Grande array shower core position, shower direction, and the total number of electrons are reconstructed for events with primary energy above 10 16.5 eV . In addition, the experiment consists of different detector setups for measuring muons at various energy thresholds between 230 MeV and 2.4 GeV. These informations are used to estimate the muon shower size as well as observables sensitive to differences of hadronic interaction models embedded in shower simulation codes. We report the goals and the status of the different muon measurements at KASCADE-Grande.

On basis of the theorem of a universal shower development stating that a hadronically generated extensive air shower is completely described by the primary energy, the position of the shower maximum and a parameter related to the total muon number, the so-called correlation curve method is developed and applied to KASCADE data. Correlation information of the muon and electron content of showers measured by the KASCADE experiment are used for the reconstruction of energy and mass of primary cosmic rays. Systematic uncertainties of the method and the results are discussed in detail. It is shown that by this method general tendencies in spectrum and composition indeed can be revealed, but the absolute normalization in energy and mass scale requires much more detailed simulations., Comment: article accepted for publication in Astroparticle Physics

Extensive air showers measured by the KASCADE–Grande experiment at the Forschungszentrum Karlsruhe are studied with respect to the arrival times of electrons and muons at observation level. The mean and the spread of the arrival time distributions have been used to determine the average time profile of the electromagnetic and muonic shower disk. For core distances R > 200 m particles of the muonic shower component arrive on average earlier at observation level than particles of the electromagnetic shower component. The difference increases with the core distance from Δ 〈 t 〉 = ( 12.9 ± 0.2 ) ns at R > 200 m to Δ 〈 t 〉 = ( 47 ± 1 ) ns at R = 500 m , where the width of the muonic and electromagnetic shower disks are comparable. This difference in arrival time is used to separate the electrons and muons dependent on the distance from the shower center. This is intended to be used by experiments with time resolving detectors.

Contains fulltext : 36597.pdf (Publisher’s version ) (Open Access) The energy spectrum of cosmic rays, following over large energy ranges a simple power law, steepens at energies around 4 PeV. This so-called knee is believed to be an imprint of corresponding steepenings or even cut-offs in the energy spectra of single cosmic ray elements, thus implying a change of composition in the range between 1 PeV and 100 PeV. One of the sophisticated experiments aiming at detailed measurements in the knee region is the KASCADE experiment and its successor, KASCADE-Grande. In the following, existing data on the knee and their limitations are briefly discussed. Concluding, an update on the KASCADE composition analysis is presented.

The WILLI detector, installed in the National Institute of Physics and Nuclear Engineering — Horia Hulubei Bucharest has been devised for studies of atmospheric muons, in particular of the muon charge ratio. We report on the results of studies for various muon energies (pμ < 1 GeV/c). The results are compared with Monte‐Carlo simulations performed with the CORSIKA and GEANT codes. We are exploring the potential of a small detector array to be set up nearby the actual WILLI detector for triggering the muon charge ratio measurements by Extended Air Shower (EAS) events.

With the KASCADE-Grande Muon Tracking Detector it was possible to measure with high accuracy directions of EAS muons with energy above 0.8 GeV and up to 700 m distance from the shower centre. Reconstructed muon tracks allow investigation of muon pseudorapidity (η) distributions. These distributions are nearly identical to the pseudorapidity distributions of their parent mesons produced in hadronic interactions. Comparison of the η distributions from measured and simulated showers can be used to test the quality of the high energy hadronic interaction models. The pseudorapidity distributions reflect the longitudinal development of EAS and, as such, are sensitive to the mass of the cosmic ray primary particles. With various parameters of the η distribution, obtained from the Muon Tracking Detector data, it is possible to calculate the average logarithm of mass of the primary cosmic ray particles. The results of the < ln A > analysis in the primary energy range 1016 eV-1017 eV with the 1st quartile and the mean value of the distributions will be presented for the QGSJet-II-2, QGSJet-II-4, EPOS 1.99 and EPOS LHC models in combination with the FLUKA model.

The atmospheric muon flux have been simulated using the CORSIKA code for two different geographical positions (Bucharest: 44°N, 26°E and Hiroshima: 34°N, 132°E). The simulations have been done for different angles of incidence between 0° and 70°. The comparison between the simulations and the experiment have been done using the measurements of the muon charge ratio with the WILLI detector in Bucharest. The results of the Monte Carlo simulations of the muon flux for the geographical positions of Hiroshima and Bucharest are compared with the semi-analytical formulae of Judge and Nash, and of Gaisser for different angles of incidence between 0° and 70° and with experimental results of the Bess experiment (vertical incidence). Various sensitivities of the approach of Judge and Nash, in particular to variations of the pion and kaon production spectra have been studied.

The KASCADE‐Grande experiment measures extensive air showers induced by cosmic rays in the knee region (with energies between 0.5 PeV and 1 EeV). The principal task of the experiment is to measure precisely the energy and chemical composition of primary cosmic rays to clarify the origin of the knee. The data of the original KASCADE experiment have been used in a composition analysis, which shows the knee is caused by a steepening of the element spectra. The limitations to these conclusions due to the dependence on the high energy hadronic interaction models used in the simulations are also presented.

Occasionally cosmic-ray induced air showers result in single, unaccompanied hadrons at ground level. Such events are investigated with the 300 m2 hadron calorimeter of the KASCADE-Grande experiment. It is an iron sampling calorimeter with a depth of 11 hadronic interaction lengths read out by warm-liquid ionization chambers. The longitudinal shower development is discussed as function of energy up to 30 TeV and the results are compared with simulations using the GEANT/FLUKA code. In addition, results of test measurements at a secondary particle beam of the Super Proton Synchrotron at CERN up to 350 GeV are discussed.

Recent results from the multi-detector set-up 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 primaries at around 100 PeV. To investigate this energy region KASCADE has recently been extended by a factor 10 in area to the new experiment KASCADE-Grande. Main results of KASCADE as well as set-up, capabilities, and status of KASCADE-Grande are presented.

KASCADE-Grande is a multi-detector setup to get redundant information on single air shower basis. The information is used to perform multi-parameter analyses to solve the threefold problem of the reconstruction of the unknown primary energy, the primary mass, and to quantify the characteristics of the hadronic interactions in the air-shower development. This contribution discusses the various ways of testing the hadronic interaction mechanisms with data of the original KASCADE experiment and their results, as well as the capabilities in testing the models with the extension of KASCADE, the KASCADE-Grande experiment. Though no hadronic interaction model is fully able to describe the multi-parameter data of KASCADE consistently, the more recent models or improved versions of older models reproduce the data better than a few years ago.

A compact device of 10 modules, each consisting of 1 cm lead, 3 cm plastic scintillator and 1 cm aluminum is set up. Cosmic ray muons with primary energies in the range 0.4 ÷ 0.9 GeV and incident angles up to 50° are stopped and decay in the device. Positive muons stopped in the different layers decay with their free life time of 2.2 μs , while the negative muons are captured by the atoms and build muonic atoms. Their reduced life time in these systems, i.e. 0.88 μs in aluminum, is measured by a dedicated multiple time digitizer. An analysis of the combined decay spectrum on the basis of a Monte Carlo simulation using the GEANT code leads to the μ + / μ − ratio of 1.20 ± 0.06 for a mean muon energy of 0.52 GeV.

Lateral distributions for electrons and muons in extensive air showers measured with the array of the KASCADE experiment are compared to results of simulations based on the high-energy hadronic interaction models QGSJet and SIBYLL. It is shown, that the muon distributions are well described by both models. Deviations are found for the electromagnetic component, where both models predict a steeper lateral shape than observed in the data. For both models the observed lateral shapes of the electron component indicate a transition from a light to a more heavy composition of the cosmic ray spectrum above the knee., Comment: 27 pages, accepted for publication in Astropart. Phys

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 ~50 Mpc through interactions with the cosmic microwave background. As there are no sufficient powerful accelerators within this distance from the Galaxy, explanations for UHECRs range from unusual astrophysical sources to exotic string physics. Also unclear is whether UHECRs consist of protons, heavy nuclei, neutrinos or gamma-rays. To resolve these questions, larger detectors with higher duty cycles and which combine multiple detection techniques are needed. Radio emission from UHECRs, on the other hand, is unaffected by attenuation, has a high duty cycle, gives calorimetric measurements and provides high directional accuracy. Here we report the detection of radio flashes from cosmic-ray air showers using low-cost digital radio receivers. We show that the radiation can be understood in terms of the geosynchrotron effect. Our results show that it should be possible to determine the nature and composition of UHECRs with combined radio and particle detectors, and to detect the ultrahigh-energy neutrinos expected from flavour mixing., Nature, May 19, 2005 issue (PDF, 14 pages), http://www.astro.ru.nl/lopes/?loc=publications

A composition analysis of KASCADE air shower data is performed by means of unfolding the two-dimensional frequency spectrum of electron and muon numbers. Aim of the analysis is the determination of energy spectra for elemental groups representing the chemical composition of primary cosmic rays. Since such an analysis depends crucially on simulations of air showers the two different hadronic interaction models QGSJet and SIBYLL are used for their generation. The resulting primary energy spectra show that the knee in the all particle spectrum is due to a steepening of the spectra of light elements but, also, that neither of the two simulation sets is able to describe the measured data consistently over the whole energy range with discrepancies appearing in different energy regions., Comment: 39 pages, accepted for publication in Astropart. Phys

Results from the KASCADE air shower experiment investigating the origin of cosmic rays in the energy region from 10^13 to 10^17 eV are presented. Attention is drawn on the investigation of interactions in the atmosphere and the energy spectrum and mass composition of cosmic rays., Comment: 8 pages, Invited talk, Astrophysical Sources of High Energy Particles and Radiation, Torun, June 20 - 24, 2005

The geometric distribution of high-energy hadrons >100 GeV in shower cores measured with the KASCADE calorimeter is analyzed. The data are checked for sensitivity to hadronic interaction features and indications of new physics as discussed in the literature. The angular correlation of the most energetic hadrons and in particular the fraction of events with hadrons being aligned are quantified by means of the commonly used parameter lambda_4. The analysis shows that the observed lambda_4 distribution is compatible with that predicted by simulations and is not linked to an angular correlation from hadronic jet production at high energy. Another parameter, d_4^max, describing distances between hadrons measured in the detector, is found to be sensitive both to the transverse momenta in secondary hadron production and the primary particle type. Transverse momenta in high-energy hadron interactions differing by a factor two or more from what is assumed in the standard simulations are disfavoured by the measured d_4^max distribution., 8 pages, 9 figures; accepted for publication by Phys. Rev. D

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 under development. Using high bandwidth ADCs and fast data processing it it will be able to filter out most of the interference. By storing the whole waveform information in digital form one can analyze transient events like air showers even after they have been recorded. To test this new technology and to demonstrate its ability to measure air showers a "LOFAR Prototype Station" (LOPES) is set up to operate in conjunction with an existing air shower array (KASCADE-Grande). The first phase consisting of 10 antennas is already running. It operates in the frequency range of 40 to 80 MHz, using simple short dipole antennas and direct 2nd Nyquist sampling of the incoming wave. It has proven to be able to do simple astronomical measurements, like imaging of a solar burst. It has also demonstrated how digital interference suppression and beamforming can overcome the problem of radio interference and pick out air shower events.

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 sqm equipped with 37 plastic scintillator stations sensitive to measure energy deposits and arrival times of air shower particles. LOPES is a small radio antenna array to operate in conjunction with KASCADE-Grande in order to calibrate the radio emission from cosmic ray air showers. Status and capabilities of the KASCADE-Grande experiment and the LOPES project are presented., Comment: To appear in Nuclear Physics B, Proceedings Supplements, as part of the volume for the CRIS 2004, Cosmic Ray International Seminar: GZK and Surroundings

The main aim of the KASCADE extensive air shower (EAS) experiment is the determination of the chemical composition of cosmic rays in the energy range around and above the knee at Ek ≈ 3 PeV. A large number of observables are measured simultaneously for each individual event, by the combination of various detection techniques for the electromagnetic, the muonic, and the hadronic component of the extensive air showers. Detailed investigations have been performed with the data measured by the KASCADE experiment since the start of data taking at the end of 1995. The results allow to evaluate hadronic interaction models, used in simulations to interpret air shower data. The all-particle spectrum of cosmic rays and their mass composition, as well as individual spectra for groups of elements have been reconstructed in the energy range between 1015 and 1017 eV . The results suggest, the knee in the all-particle cosmic-ray energy spectrum is caused by a rigidity-dependent cut-off of individual element groups. To improve the statistics around 1017 eV, where the “iron knee” in the cosmic ray spectrum is indicated in our data, the KASCADE experiment has recently been extended to KASCADE-Grande by a large collecting area (0.5km2) electromagnetic array, contributed from the former EAS-TOP experiment. The Grande part will cover the primary energy range 1016 eV

The fluxes of atmospheric muons and neutrinos are calculated by a three dimensional Monte Carlo simulation with the air shower code CORSIKA using the hadronic interaction models DPMJET, VENUS, GHEISHA, and UrQMD. For the simulation of low energy primary particles the original CORSIKA has been extended by a parametrization of the solar modulation and a microscopic calculation of the directional dependence of the geomagnetic cut-off functions. An accurate description for the geography of the Earth has been included by a digital elevation model, tables for the local magnetic field in the atmosphere, and various atmospheric models for different geographic latitudes and annual seasons. CORSIKA is used to calculate atmospheric muon fluxes for different locations and the neutrino fluxes for Kamioka. The results of CORSIKA for the muon fluxes are verified by an extensive comparison with recent measurements. The obtained neutrino fluxes are compared with other calculations and the influence of the hadronic interaction model, the geomagnetic cut-off and the local magnetic field on the neutrino fluxes is investigated., revtex, 19 pages, 19 Postscript figures, submitted to Phys. Rev. D

We report the first direct measurement of the overall characteristics of microwave radio emission from extensive air showers. Using a trigger provided by the KASCADE-Grande air shower array, the signals of the microwave antennas of the CROME (Cosmic-Ray Observation via Microwave Emission) experiment have been read out and searched for signatures of radio emission by high-energy air showers in the GHz frequency range. Microwave signals have been detected for more than 30 showers with energies above 3*10^16 eV. The observations presented in this Letter are consistent with a mainly forward-directed and polarised emission process in the GHz frequency range. The measurements show that microwave radiation offers a new means of studying air showers at energies above 10^17 eV., Accepted for publication in PRL

Measurements of electron, muon, and hadron lateral distributions of extensive air showers as recorded by the KASCADE experiment are presented. The data cover the energy range from about 5x10^14 eV up to almost 10^17 eV and extend from the inner core region to distances of 200 m. The electron and muon distributions are corrected for mutual contaminations by taking into account the detector properties in the experiment. All distributions are well described by NKG-functions. The scale radii describing the electron and hadron data best are approx. 30 m and 10 m, respectively. We discuss the correlation between scale radii and `age' parameter as well as their dependence on shower size, zenith angle, and particle energy threshold., Comment: 28 pages, 14 figures, Accepted for publication in Astroparticle Physics

The temporal structure of the extensive air shower (EAS) muon component (E-thres = 2.4 GeV) is studied at sea level by measurements of the muon arrival time distributions using the muon detection facilities of the KASCADE central detector. Data have been analysed for EAS core distances up to 110 m for primary energies around the knee region. The time structure of the EAS muon component is represented by the distributions of the mean, median, first quartile and the third quartile of the muon arrival time distributions relative to the foremost muon. The EAS time profiles (variation with the distance from the EAS center) are studied along their dependencies on the angle of incidence and the energy-indicative muon number N-mu(tr). Effects of the fluctuation of the arrival time of the first registered muon are scrutinised and corrected. The experimental results are compared with EAS Monte Carlo (CORSIKA-GEANT) simulations, fully including the detector responses and illustrating the phenomenological features. The comparisons, though generally in fair global agreement, revealed that the simulations underestimate the shower thickness and show nearly no dependence on the mass composition if the time resolution of the apparatus is realistically taken into account. (C) 2001 Elsevier Science B.V. All rights reserved.

The experimental results of the KASCADE Extensive Air Shower experiment have been searched for events which might be attributed to high energy primary gamma rays. The observed data are compared with simulated gamma showers. Events with a very low muon to electron ratio, a smooth lateral electron distribution and an age characteristic of gamma induced events are selected. This contribution describes the applied methods. So far only a very small fraction of the KASCADE results has been studied and no positive identification can yet be claimed.

The main goals of the KASCADE (KArlsruhe Shower Core and Array DEtector) experiment are the determination of the energy spectrum and elemental composition of the charged cosmic rays in the energy range around the knee at ca. 5 PeV. Due to the large number of measured observables per single shower a variety of different approaches are applied to the data, preferably on an event-by-event basis. First results are presented and the influence of the high-energy interaction models underlying the analyses is discussed., 3 pages, 3 figures included, to appear in the TAUP 99 Proceedings, Nucl. Phys. B (Proc. Suppl.), ed. by M. Froissart, J. Dumarchez and D. Vignaud

We present the design and first test results of a new FADC-based data acquisition (DAQ) system for the Grande array of the KASCADE-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 $10^{18}$ 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. events per second. Two Grande stations have been equipped with the FADC-based data acquisition system and first data are shown., Comment: 7 pages, 8 figures

A. HAUNGS, W.D. APEL, F. BADEA, L. BAHREN , K. BEKK, A. BERCUCI , M. BERTAINA, P.L. BIERMANN, J. BLUMER , H. BOZDOG, I.M. BRANCUS , M. BRUGGEMANN, P. BUCHHOLZ, S. BUITINK , H. BUTCHER , A. CHIAVASSA, K. DAUMILLER, A.G. DE BRUYN, C.M. DE VOS, F. DI PIERRO, P. DOLL, R. ENGEL, J. ENGLER, H. FALCKE , H. GEMMEKE , P.L. GHIA , H.-J. GILS, R. GLASSTETTER , C. GRUPEN, D. HECK, J.R.HORANDEL , A. HORNEFFER, T. HUEGE , K.-H.KAMPERT , G.W. KANT , H.O. KLAGES, U. KLEIN, Y. KOLOTAEV, Y. KOOPMAN, O. KROMER , J. KUIJPERS , S. LAFEBRE , G. MAIER, H.J. MATHES, H.J. MAYER, J. MILKE, B. MITRICA , C. MORELLO , M. MULLER, G. NAVARRA, S. NEHLS, A. NIGL , R. OBENLAND, J. OEHLSCHLAGER, S. OSTAPCHENKO, S. OVER, H.J. PEPPING , M. PETCU , J. PETROVIC , T. PIEROG, S. PLEWNIA, H. REBEL, A. RISSE , M. ROTH , H. SCHIELER, G. SCHOONDERBEEK, O. SIMA , M. STUMPERT , G. TOMA , G.C. TRINCHERO , H. ULRICH, J.VAN BUREN, W.VAN CAPELLEN , W. WALKOWIAK, A. WEINDL, S. WIJNHOLDS, J. WOCHELE, J. ZABIEROWSKI , J.A. ZENSUS, D. ZIMMERMANN A Institut fur Kernphysik, Forschungszentrum Karlsruhe, Germany B ASTRON Dwingeloo, The Netherlands C NIPNE Bucharest, Romania D Dpt di Fisica Generale dell’Universita Torino, Italy E Max-Planck-Institut fur Radioastronomie, Bonn, Germany F Institut fur Experimentelle Kernphysik, Uni Karlsruhe, Germany, G Fachbereich Physik, Universitat Siegen, Germany H Dpt of Astrophysics, Radboud Uni Nijmegen, The Netherlands I IPE, Forschungszentrum Karlsruhe, Germany J Ist di Fisica dello Spazio Interplanetario INAF, Torino, Italy K Fachbereich Physik, Uni Wuppertal, Germany L Radioastronomisches Institut der Uni Bonn, Germany M Soltan Institute for Nuclear Studies, Lodz, Poland

LOPES was a digital antenna array detecting the radio emission of cosmic-ray air showers. The calibration of the absolute amplitude scale of the measurements was done using an external, commercial reference source, which emits a frequency comb with defined amplitudes. Recently, we obtained improved reference values by the manufacturer of the reference source, which significantly changed the absolute calibration of LOPES. We reanalyzed previously published LOPES measurements, studying the impact of the changed calibration. The main effect is an overall decrease of the LOPES amplitude scale by a factor of $2.6 \pm 0.2$, affecting all previously published values for measurements of the electric-field strength. This results in a major change in the conclusion of the paper 'Comparing LOPES measurements of air-shower radio emission with REAS 3.11 and CoREAS simulations' published in Astroparticle Physics 50-52 (2013) 76-91: With the revised calibration, LOPES measurements now are compatible with CoREAS simulations, but in tension with REAS 3.11 simulations. Since CoREAS is the latest version of the simulation code incorporating the current state of knowledge on the radio emission of air showers, this new result indicates that the absolute amplitude prediction of current simulations now is in agreement with experimental data., Comment: Partly changes results and conclusion of publication Astroparticle Physics 50-52 (2013) 76-91 (arXiv:1309.5920)

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.

We measured the transmission of radio signals through salt in the ’Unirea’ salt mine (Slanic Prahova, Romania) at a depth of 208 m, in 3 frequency bands: around 200 MHz, 400 MHz and 800 MHz. We concluded that the higher ones are not suitable for radio detection of cosmic neutrinos. Estimates about the comparative radiowave attenuation after 10 m of propagation, to 100 m were made, at 200 MHz.