Precise measurements of hydrogen and helium isotopes with BESS-Polar II

A precise knowledge of cosmic-ray hydrogen and helium isotopes provides important information to better understand Galactic cosmic-ray propagation. Deuteron and helium 3 species are mainly secondary particles created by the spallation of primary proton and helium 4 particles during their propagation in the Galaxy. Secondary-to-primary ratios thus bring direct information on the average amount of material traversed by cosmic rays in the interstellar medium. The Balloon-borne Experiment with Superconducting Spectrometer BESS-Polar II flew over Antarctica for 24.5 days from December 2007 through January 2008, during the 23rd solar cycle minimum. The instrument is made of complementary particle detectors which allow to precisely measure the charge, velocity and rigidity of incident cosmic rays. It can accurately separate and precisely measure cosmic-ray hydrogen and helium isotopes between 0.2 and 1.5 GeV/nucleon. These data, which are the most precise to date, will be reported and their implications will be discussed

Search for Magnetic Monopoles with the ANTARES Detector

The ANTARES neutrino telescope is fully operational since May 2008. Located at a depth of ~ 2500 m in the Mediterranean Sea, 40 km off the Provencal coast, it comprises a large three-dimensional array of 885 Optical Modules deployed on 12 vertical lines. The telescope is aimed to observe high energy cosmic neutrinos through the detection of the Cherenkov light produced by up-going induced muons. Besides the detection of high energy neutrinos, the ANTARES telescope offers an opportunity to improve sensitivity to exotic cosmological relics, like magnetic monopoles. Monopoles are hypothetical particles initially predicted by Dirac in 1931, and reintroduced some decades later in a large class of Grand Unified Theories. Relativistic magnetic monopoles can emit a large amount of Cherenkov light when passing through matter, with intensity 8500 times higher than that radiated from a muon. Dedicated trigger algorithms and search strategies have been developed to search for such bright objects with the ANTARES detector. The data filtering, background rejection and final selection criteria will be described, as well as the expected sensitivity of ANTARES to exotic physic

The cosmic ray energetics and mass for the international space station (ISS-CREAM) instrument

International audienceThe ISS-CREAM instrument is the modified version of the Cosmic Ray Energetics And Mass (CREAM) experiment, which was flown on balloons multiple times over Antarctica and later installed on the International Space Station (ISS). Its primary objective is to measure the energy spectra of individual cosmic-ray elements for the charge range of Z = 1 to Z = 26, in the energy range of ∼ 1012 to ∼ 1015 eV. The instrument comprises a tungsten/scintillator calorimeter and a pixelated silicon charge detector as primary detectors to determine the energy and charge of cosmic rays. Additionally, it includes top and bottom scintillator counting detectors and a boronated scintillator detector to differentiate between electrons and hadrons for multi-TeV electron measurements. The ISS-CREAM instrument was installed on the ISS in August 2017 and operated until February 2019. This paper provides an overview of the instrument, focusing on its detectors, trigger systems, common electronics, and power systems. The paper highlights the modifications made to these components to optimize their performance for ISS operations

The boronated scintillator detector of the ISS-CREAM experiment

International audienceThe Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM) instrument is a next-generation experiment for the direct detection and study of cosmic-ray nuclei and electrons. With a long exposure in low Earth orbit, the experiment will determine the particle fluxes and spectral details of cosmic-ray nuclei from hydrogen to iron, over an energy range of about 1012 eV to > 1015 eV, and of cosmic-ray electrons over an energy range of about 5 × 1010 eV to > 1013 eV. The instrument was deployed to the ISS in August 2017 on the SpaceX CRS-12 mission. We review the design, implementation and performance of one of the ISS-CREAM detector systems: a boron loaded scintillation detector used in discriminating electron-induced events from the much more abundant cosmic-ray nuclei

Performance of the BACCUS Transition Radiation Detector

International audienceThe Boron And Carbon Cosmic rays in the Upper Stratosphere (BACCUS) balloon-borne exper-iment flew for 30 days over Antarctica in December 2016. It is the successor of the CREAMballoon program in Antarctica which recorded a total cumulative exposure of 161 days. BAC-CUS is primarily aimed to measure cosmic-ray boron and carbon fluxes at the highest energiesreachable with a balloon or satellite experiment, in order to provide essential information for abetter understanding of cosmic-ray propagation in the Galaxy. The payload is made of multipleparticle physics detectors which measure the charge up to Z=26 and energy of incident particlesfrom a few hundred GeV to a few PeV. The newly designed Transition Radiation Detector (TRD)measures signals that are a function of the charge and Lorentz factor. In April 2016, BACCUSwas taken to CERN in its flight configuration to characterize its detectors’ response to beams ofelectrons and pions. The performance of the TRD using beam test data are reported in this paper

Measurement of delayed fluorescence in plastic scintillator from 1 to 10 μ\mus

International audienceThe time dependence of the relative light emission of Eljen Technology EJ-200 polyvinyltoluene-based plastic scintillator was measured between 1 and 10μs after the passage of a particle shower, a singly charged particle (atmospheric muon), and with a UV LED exciting the fluor. This was compared in magnitude to the integrated response for the prompt light (within 500 ns of excitation). A model with a time-dependent yield consisting of three exponentially decaying components (fast, medium, and slow) was developed to fit the data. Note that the exact time structure of early (< 1μs ) light emission was not measured for individual components, only for all three components together This model assumes all three components share the same rise time. The decay time constants of the fast, medium and slow components are, respectively, 7.8 ns, 490 ns, and 2370 ns. The relative total normalized yields for each component are: fast 95.8%, medium 2.2%, and slow 2.0%

Performance of the ISS-CREAM Calorimeter

International audienceThe Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM) is scheduled for launch in 2017. It is designed to directly measure and identify theelemental composition of incident Galactic cosmic rays from a few hundred GeV to PeV energies.Such large energy range sensitivity is reached by using an electromagnetic sampling calorimeter(CAL) which measures the energy deposit of particle-induced showers. The CAL is composedof twenty layers of tungsten plates interleaved with scintillating fibers, and glued together usingepoxy-coated fiberglass to comply with space launch requirements. In August 2015, beam testmeasurements were performed at CERN to verify the performance of the CAL using layers ofepoxy-coated fiberglass placed between tungsten plates. The CAL response to electron and pionbeams and its performance are reported and compared with previous beam test configurations