Showing papers by "J. Oehlschläger published in 2017"
62 citations
TL;DR: In this paper, the evolution of the muon content of very high energy air showers (EAS) in the atmosphere is investigated with data of the KASCADE-Grande observatory.
55 citations
TL;DR: In this article, an upper bound of the flux of gamma-rays in the primary cosmic ray flux was determined in an energy range of ${10}^{14} - {10}−18}$ eV.
Abstract: KASCADE and KASCADE-Grande were multi-detector installations to measure individual air showers of cosmic rays at ultra-high energy. Based on data sets measured by KASCADE and KASCADE-Grande, 90% C.L. upper limits to the flux of gamma-rays in the primary cosmic ray flux are determined in an energy range of ${10}^{14} - {10}^{18}$ eV. The analysis is performed by selecting air showers with a low muon content as expected for gamma-ray-induced showers compared to air showers induced by energetic nuclei. The best upper limit of the fraction of gamma-rays to the total cosmic ray flux is obtained at $3.7 \times {10}^{15}$ eV with $1.1 \times {10}^{-5}$. Translated to an absolute gamma-ray flux this sets constraints on some fundamental astrophysical models, such as the distance of sources for at least one of the IceCube neutrino excess models.
37 citations
16 Aug 2017
TL;DR: In this paper, the authors studied the total muon number and the lateral density distribution of muons in EAS detected by KASCADE-Grande, a ground-based air shower array dedicated to the study of the energy and composition of cosmic rays with energies ranging from $1$ PeV to $ 1$ EeV.
Abstract: The KASCADE-Grande observatory was a ground-based air shower array
devoted to the study of the energy and composition of cosmic rays with energies
from $1$ PeV to $1$ EeV. The experiment consisted of different detector systems
which allowed the simultaneous measurement of distinct components of the air
showers (EAS), such as the muon content. In this contribution, we study the total
muon number and the lateral density distribution of muons in EAS detected
by KASCADE-Grande. The data are analyzed as a function of the zenith angle and
the total number of charged particles. The attenuation length of the muon content
of EAS is also measured. The results are compared with the predictions of the SIBYLL
$2.3$ hadronic interaction model.
7 citations
16 Aug 2017
TL;DR: The KASCADE Cosmic Ray Data Centre is a web-based platform to provide scientific data for the general public and a new version named NABOO was released, based on a completely new back-end database and software.
Abstract: 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.
1 citations
Posted Content•
TL;DR: The KASCADE air shower experiment was the first to conduct quantitative tests of hadronic interactions with air shower data as mentioned in this paper, and the results from the experiment were used to investigate the properties of cosmic rays at high energies in kinematic forward direction.
Abstract: Cosmic rays provide an unique approach to study hadronic interactions at high energies in the kinematic forward direction. The KASCADE air shower experiment was the first to conduct quantitative tests of hadronic interactions with air shower data. A brief overview is given on results from KASCADE and its extension KASCADE-Grande with respect to investigations of hadronic interactions and the properties of cosmic rays.
1 citations
TL;DR: The KASCADE-Grande experiment has significantly contributed to the current knowledge about the energy spectrum and composition of cosmic rays for energies between the knee and the ankle as mentioned in this paper, and a new, combined analysis of both arrays, kASCADE and Grande, was developed significantly increasing the accuracy of the shower observables.
Abstract: The KASCADE-Grande experiment has significantly contributed to the current knowledge about the energy spectrum and composition of cosmic rays for energies between the knee and the ankle. Meanwhile, post-LHC versions of the hadronic interaction models are available and used to interpret the entire data set of KASCADE-Grande. In addition, a new, combined analysis of both arrays, KASCADE and Grande, was developed significantly increasing the accuracy of the shower observables. First results of the new analysis with the entire data set of the KASCADE-Grande experiment will be the focus of this contribution.
1 citations
30 Jun 2017
TL;DR: In this paper, the charged particle densities obtained from CORSIKA simulated EAS, using the QGSJet-II.04 hadronic interaction model, are used for primary energy reconstruction.
Abstract: The charged particle densities obtained from CORSIKA simulated EAS, using the QGSJet-II.04 hadronic interaction model are used for primary energy reconstruction. Simulated data are reconstructed by using Lateral Energy Correction Functions computed with a new realistic model of the Grande stations implemented in Geant4.10.
1 citations
TL;DR: In this article, the results of the KASCADE-Grande air-shower experiment are compared with the expectations of the post-LHC hadronic-interaction models, EPOSLHC and QGSJET-II-04, in order to test the validity of the model predictions.
1 citations
16 Aug 2017
TL;DR: In this article, a new analysis of the combined data from the arrays of KASCADE and KASCade-Grande was performed, increasing both the effective area and the accuracy of the air shower reconstruction.
Abstract: KASCADE and KASCADE-Grande were detector arrays for the measurement of extensive air showers generated by high-energy cosmic rays in the PeV to EeV energy range. KASCADE-Grande has been operated for more than two decades and completed the data taking at the end of 2013. Now, a new analysis of the combined data from the arrays of KASCADE and KASCADE-Grande was performed, increasing both the effective area and the accuracy of the shower reconstruction. In addition, new versions of post-LHC hadronic interaction models are used to interpret the combined data. First results from the new combined analysis confirming earlier observations of spectral features, but also unveiling still existing inconsistencies of the models, will be discussed in this contribution.
07 Nov 2017
TL;DR: The KASCADE air shower experiment was the first to conduct quantitative tests of hadronic interactions with air shower data as discussed by the authors, and the results from the experiment were used to investigate the properties of cosmic rays at high energies in kinematic forward direction.
Abstract: Cosmic rays provide an unique approach to study hadronic interactions at high energies in the kinematic forward direction. The KASCADE air shower experiment was the first to conduct quantitative tests of hadronic interactions with air shower data. A brief overview is given on results from KASCADE and its extension KASCADE-Grande with respect to investigations of hadronic interactions and the properties of cosmic rays.