We present the GIGAS (Gigahertz Identification of Giant Air Shower) microwave radio sensor arrays of the EASIER project (Extensive Air Shower Identification with Electron Radiometers), deployed at ...the site of the Pierre Auger cosmic ray observatory. The aim of these novel arrays is to probe the intensity of the molecular bremsstrahlung radiation expected from the development of the extensive air showers produced by the interaction of ultra high energy cosmic rays in the atmosphere. In the designed setup, the sensors are embedded within the surface detector array of the Pierre Auger observatory allowing us to use the particle signals at ground level to trigger the radio system. A series of seven, then 61 sensors have been deployed in the C-band, followed by a new series of 14 higher sensitivity ones in the C-band and the L-band. The design, the operation, the calibration and the sensitivity to extensive air showers of these arrays are described in this paper.
In France, the CNRS National Institute for Nuclear Physics and Particle Physics (CNRS/IN2P3) is involved in educational actions promoting the use of cosmic ray detectors in high schools. These ...projects are ran in close collaboration with teachers to ensure that they match the letter and spirit of the curriculum. These instruments, lent to teachers for periods ranging from a few weeks to a few years depending on the measurements possible with them, complement nicely the lectures. They allow the students to sense the elementary particles and to understand the problems raised by their detection. The well-recognized cosmodétecteur and the new COSMIX detector are described in the following, together with the COSMAX software framework, which gives a direct access to the Fermi satellite data.
We present the results of an analysis of the large angular scale distribution of the arrival directions of cosmic rays with energy above 4 EeV detected at the Pierre Auger Observatory including for ...the first time events with zenith angle between $60^\circ$ and $80^\circ$. We perform two Rayleigh analyses, one in the right ascension and one in the azimuth angle distributions, that are sensitive to modulations in right ascension and declination, respectively. The largest departure from isotropy appears in the $E > 8$ EeV energy bin, with an amplitude for the first harmonic in right ascension $r_1^\alpha =(4.4 \pm 1.0){\times}10^{-2}$, that has a chance probability $P(\ge r_1^\alpha)=6.4{\times}10^{-5}$, reinforcing the hint previously reported with vertical events alone.
We have measured the polarization of Λ\LambdaΛ hyperons produced inclusively by a Σ−\Sigma^-Σ− beam of 340 GeV/c momentum in nuclear targets. From a sample of 9.5 millions of identified Λ\LambdaΛ ...decays, polarizations were determined in the range xF>0.1x_F \gt 0.1xF>0.1 and pt≤1.6p_t\leq 1.6pt≤1.6 GeV/c . The polarization w.r.t. the production normal is mainly positive for xF≥0.3x_F \geq 0.3xF≥0.3. At fixed values of xFx_FxF, it increases with ptp_tpt to a maximum between pt=0.5p_t = 0.5pt=0.5 and pt=1p_t = 1pt=1 GeV/c , and then decreases to zero or even negative values, in sharp contrast to the plateau above pt=1p_t = 1pt=1 GeV/c observed in inclusive Λ\LambdaΛ production by protons.
Spherical harmonic moments are well-suited for capturing anisotropy at any scale in the flux of cosmic rays. An unambiguous measurement of the full set of spherical harmonic coefficients requires ...full-sky coverage. This can be achieved by combining data from observatories located in both the northern and southern hemispheres. To this end, a joint analysis using data recorded at the Telescope Array and the Pierre Auger Observatory above $10^{19}$ eV is presented in this work. The resulting multipolar expansion of the flux of cosmic rays allows us to perform a series of anisotropy searches, and in particular to report on the angular power spectrum of cosmic rays above $10^{19}$ eV. No significant deviation from isotropic expectations is found throughout the analyses performed. Upper limits on the amplitudes of the dipole and quadrupole moments are derived as a function of the direction in the sky, varying between 7% and 13% for the dipole and between 7% and 10% for a symmetric quadrupole.
We report on a measurement of the differential cross sections of inclusiveK890±K^{\pm}_{890}K890±production inσ−,pi−\sigma^-, pi^-σ−,pi−and ne. (Springer)
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