Search results for "Cosmic Ray"
showing 10 items of 301 documents
Extensive air showers and diffused Cherenkov light detection: The ULTRA experiment
2007
Abstract The Uv Light Transmission and Reflection in the Atmosphere (ULTRA) experiment has been designed to provide quantitative measurements of the backscattered Cherenkov signal associated to the Extensive Air Showers (EAS) at the impact point on the Earth surface. The knowledge of such information will test the possibility to detect the diffused Cherenkov light spot from space within the Ultra high-energy cosmic ray observation. The Cherenkov signal is necessary to give an absolute reference for the track, allowing the measurement of the shower maximum and easing the separation between neutrino and hadronic showers. In this paper we discuss the experimental set-up with detailed informati…
Intrinsic linearity of bakelite Resistive Plate Chambers operated in streamer mode
2019
Abstract Resistive Plate Chambers have largely been used in High Energy Physics and Cosmic Ray research. In view of using this detector for calorimetry applications it is important to know the maximum measurable particle density, or its intrinsic linearity limit, which is tightly related to the dimension of the discharge region. In this paper we report the results of measurements performed at the Beam Test Facility (INFN National Laboratory of Frascati, Italy) where the intrinsic linearity of bakelite RPCs operated in streamer mode has been tested at different impinging particle densities.
Search for Galactic PeV gamma rays with the IceCube Neutrino Observatory
2013
Gamma-ray induced air showers are notable for their lack of muons, compared to hadronic showers. Hence, air shower arrays with large underground muon detectors can select a sample greatly enriched in photon showers by rejecting showers containing muons. IceCube is sensitive to muons with energies above ~500 GeV at the surface, which provides an efficient veto system for hadronic air showers with energies above 1 PeV. One year of data from the 40-string IceCube configuration was used to perform a search for point sources and a Galactic diffuse signal. No sources were found, resulting in a 90% C.L. upper limit on the ratio of gamma rays to cosmic rays of 1.2 x 10^(-3)for the flux coming from …
First search for extremely high energy cosmogenic neutrinos with the IceCube Neutrino Observatory.
2010
We report on the results of the search for extremely-high energy (EHE) neutrinos with energies above $10^7$ GeV obtained with the partially ($\sim$30%) constructed IceCube in 2007. From the absence of signal events in the sample of 242.1 days of effective livetime, we derive a 90% C.L. model independent differential upper limit based on the number of signal events per energy decade at $E^2 \phi_{\nu_e+\nu_\mu+\nu_\tau}\simeq 1.4 \times 10^{-6}$ GeV cm$^{-2}$ sec$^{-1}$ sr$^{-1}$ for neutrinos in the energy range from $3\times10^7$ to $3\times10^9$ GeV.
Measurement of the energy spectrum of cosmic rays above 10^18 eV using the Pierre Auger Observatory
2010
We report a measurement of the flux of cosmic rays with unprecedented precision and Statistics using the Pierre Auger Observatory Based on fluorescence observations in coincidence with at least one Surface detector we derive a spectrum for energies above 10(18) eV We also update the previously published energy spectrum obtained with the surface detector array The two spectra are combined addressing the systematic uncertainties and, in particular. the influence of the energy resolution on the spectral shape The spectrum can be described by a broken power law E-gamma with index gamma = 3 3 below the ankle which is measured at log(10)(E-ankle/eV) = 18 6 Above the ankle the spectrum is describe…
Fragmentation of accelerated 2.1 GeV/nucleon12C,14N and16O Ions in nuclear emulsion
1975
The inelastic-interaction mean free path and fragmentation parameters in nuclear emulsion of accelerated 2.1 GeV/nucleon12C,14N and16O have been determined. The discrimination of the targets has been achieved with a new method. The global results obtained for the three ions have been compared with theM-group of the cosmic radiation.
Underground multimuon experiment in the Pyhäsalmi mine
2006
An experiment to observe simultaneous, multiple muon events originating from extensive air showers is under preparation. The experiment will be situated in shallow depths in the Pyhasalmi mine in Finland, where the existing free caverns will be used. The aim is to cover an area of about 200 - 300 m(2). The detection of the multimuon events is motivated by partly unknown composition of the primary cosmic rays in the energy region of 10(15) - 10(16) eV, i.e. the 'knee' region. A prototype detector is under construction and is expected to be running at the spring 2005.
Status of the CosmoLep project
1997
The C osmo L ep project was proposed as an experiment to look for coincidences between the four L ep detectors, caused by cosmic ray events larger than conventional extensive air showers. Currently a pilot experiment is in operation, which is using the A leph hadron calorimeter and several scintillator arrays in and near the A leph cavern.
<title>Studies of the activation background in CsI(Tl) detectors</title>
1993
CsI scintillation crystals are widely used as detection in (gamma) -ray astronomy observations. In the MeV energy region, one of the most important background sources in CsI is the (beta) decays induced in the crystal by cosmic ray protons and their secondaries. One recent idea for reducing this background is to use discrete detector arrays to reject the large amount of localized (beta) decay events. Two experiments were carried out with 1 cm3 CsI crystals bombarded with energetic proton beams and fast/thermal neutrons, with the aim of evaluating the effectiveness of this method in pixelated (1 cm3) CsI detectors. The ratio of the number of decays resulting in single site and multiple site …
Expansion cone for the 3-inch PMTs of the KM3NeT optical modules
2013
[EN] Detection of high-energy neutrinos from distant astrophysical sources will open a new window on the Universe. The detection principle exploits the measurement of Cherenkov light emitted by charged particles resulting from neutrino interactions in the matter containing the telescope. A novel multi-PMT digital optical module (DOM) was developed to contain 31 3-inch photomultiplier tubes (PMTs). In order to maximize the detector sensitivity, each PMT will be surrounded by an expansion cone which collects photons that would otherwise miss the photocathode. Results for various angles of incidence with respect to the PMT surface indicate an increase in collection efficiency by 30% on average…