Test of large area glass RPCs at the DA Phi NE Test Beam Facility (BTF)

Abstract The CaPiRe program has been started to develop a new detector design, in order to produce large areas of glass Resistive Plate Chambers (RPC) detectors, overcoming the previous limitations. As a first step we produced our glass RPC detectors ( 1 m 2 ) at General Tecnica exploiting their standard procedures, materials and production techniques simply using 2 mm glass electrodes instead of the bakelite ones. A set of RPC was produced by using pre-coated (silk screen printed) electrodes, while others were produced with the standard graphite coating. All the detectors, together with four old Glass RPC acting as reference, were tested at the DA Φ NE Test Beam Facility with 500 MeV electrons in order to study the efficiency in different positions inside the detectors (i.e. near spacers and edges) and to study the detector behavior as a function of the local particle rate

Local anisotropy of muon flux during Forbush decreases from URAGAN data

The approach to the analysis of spatial-angular characteristics of the muon flux variations at different phases of Forbush decrease development according to the muon snapshots (muongraphies) obtained using muon hodoscope URAGAN, as well as the analysis results are presented

Temperature effect corrections for URAGAN based on CAO, GDAS, NOAA data

For the analysis of muon flux variations caused by extra-atmospheric processes it is necessary to introduce corrections for meteorological effects. For temperature effect (TE) correction it is necessary to know the temperature profile of the atmosphere. As a rule, this profile is measured by meteorological balloons two or four times a day. Alternative sources are satellite observations and data obtained from models of atmosphere used for weather forecasting. Vertical temperature profiles obtained from NOAA satellites, GDAS (Global Data Assimilation System) and CAO data (Central Aerological Observatory, Russia) for standard isobaric levels were compared. Mean value of temperature difference for most levels does not exceed 1 K. Comparison of URAGAN data corrected for TE with CAO information, satellites and GDAS shows a good agreement. Counting rate and anisotropy of the muon flux corrected for meteorological effects for 2007-2014 are presented

Measurements of the energy deposit of inclined muon bundles in the CWD NEVOD

First results of investigations of the energy deposits of inclined muon bundles in the ground-based Cherenkov water detector NEVOD are presented. As a measure of the muon bundle energy deposit, the total number of photoelectrons detected by PMTs of the Cherenkov calorimeter is used. For each event, the local muon density at the observation point and the muon bundle arrival direction are estimated from the data of the coordinate-tracking detector DECOR. Registration of the bundles in a wide range of zenith angles allows to explore the interval of primary particle energies from ̃ 1016 to ̃ 1018 eV. Measurement results are compared with CORSIKA based simulations of EAS muon component. It is found that the mean energy of muons detected in the bundles rapidly increases with the zenith angle and reaches about 500 GeV near the horizon

A comparison of the cosmic-ray energy scales of Tunka-133 and KASCADE-Grande via their radio extensions Tunka-Rex and LOPES

The radio technique is a promising method for detection of cosmic-ray air showers of energies around $100\,$PeV and higher with an array of radio antennas. Since the amplitude of the radio signal can be measured absolutely and increases with the shower energy, radio measurements can be used to determine the air-shower energy on an absolute scale. We show that calibrated measurements of radio detectors operated in coincidence with host experiments measuring air showers based on other techniques can be used for comparing the energy scales of these host experiments. Using two approaches, first via direct amplitude measurements, and second via comparison of measurements with air shower simulations, we compare the energy scales of the air-shower experiments Tunka-133 and KASCADE-Grande, using their radio extensions, Tunka-Rex and LOPES, respectively. Due to the consistent amplitude calibration for Tunka-Rex and LOPES achieved by using the same reference source, this comparison reaches an accuracy of approximately $10\,\%$ - limited by some shortcomings of LOPES, which was a prototype experiment for the digital radio technique for air showers. In particular we show that the energy scales of cosmic-ray measurements by the independently calibrated experiments KASCADE-Grande and Tunka-133 are consistent with each other on this level

Search for Event Rate Modulation in XENON100 Electronic Recoil Data

We have searched for periodic variations of the electronic recoil event rate in the (2-6) keV energy range recorded between February 2011 and March 2012 with the XENON100 detector, adding up to 224.6 live days in total. Following a detailed study to establish the stability of the detector and its background contributions during this run, we performed an un-binned profile likelihood analysis to identify any periodicity up to 500 days. We find a global significance of less than 1 sigma for all periods suggesting no statistically significant modulation in the data. While the local significance for an annual modulation is 2.8 sigma, the analysis of a multiple-scatter control sample and the phase of the modulation disfavor a dark matter interpretation. The DAMA/LIBRA annual modulation interpreted as a dark matter signature with axial-vector coupling of WIMPs to electrons is excluded at 4.8 sigma.Comment: 6 pages, 4 figure

EAS array of the NEVOD Experimental Complex

A new setup for registration of the electromagnetic component of the EAS at the “knee” region of the energy spectrum of primary cosmic rays (PCR) is now under construction on the basis of the experimental complex NEVOD-DECOR (Moscow, Russia). The EAS array detecting system has a cluster organization. Clusters are located in the MEPhI campus. The specific features of the array registering system that provides particle detection, data acquisition, cluster synchronization and events selection are discussed. The results of counter characteristics study are also presented

On a coherent investigation of the spectrum of cosmic rays in the energy range of 10(14) - 10(18) eV with KASCADE and KASCADE-Grande

The KASCADE experiment and its extension KASCADE-Grande have significantly contributed to the current knowledge about the energy spectrum and composition of cosmic rays (CRs) with energies between the knee and the ankle. However, the data of both experiments were analysed separately, although Grande used the muon information of the KASCADE-array. A coherent analysis based on the combined data of both arrays is expected to profit from reconstructed shower observables with even higher accuracy compared to the stand-alone analyses. In addition, a significantly larger fiducial area is available. The aim of this analysis is to obtain the spectrum and composition of CRs in the range from 1014 to 1018 eV with a larger number of events and further reduced uncertainties using one unique reconstruction procedure for the entire energy range. This contribution will describe the motivation, the concept, and the current status of the combined analysis

The KASCADE-Grande observatory and the composition of very high-energy cosmic rays

KASCADE-Grande is an air-shower observatory devoted to the detection of cosmic rays with energies in the range of 1016 to 1018 eV. This energy region is of particular interest for the cosmic ray astrophysics, since it is the place where some models predict the existence of a transition from galactic to extragalactic origin of cosmic rays and the presence of a break in the flux of its heavy component. The detection of these features requires detailed and simultaneous measurements of the energy and composition of cosmic rays with sufficient statistics. These kinds of studies are possible for the first time in KASCADE-Grande due to the accurate measurements of several air-shower observables, i.e., the number of charged particles, electrons and muons in the shower, using the different detector systems of the observatory. In this contribution, a detailed look into the composition of 1016 — 1018 eV cosmic rays with KASCADE-Grande is presented