200 GEV AMU 32S+PB ハンノウ ニオケル ヨコ ホウコウ ウンドウリョウ ブンプ ト クラスター カイセキ CERN EXPERIMENT EMU 05

EMU05実験は, 磁陽中に配置したエマルション・チェンバー(MAGIC : Magnetic-Interactive-Emulsion-chamber)によって, 200GeV/AMU^S+Pb反応で生成された荷電二次粒子の横方向運動量(P_T)分布及び粒子相関の解析を行った.P_T分布は, ターゲット及び中央ラピディティ領域のどちらもP_0(slope value)が160から200MeV/cの一成分の線形指数分布でフィットすることができ, P_0>300MeV/c領域における分布の異常な増大は観測されなかった.また, 荷電符号のラピディティー方位角空間でのクラスター解析の結果, シミュレーション(ランダム)と比較して統計的に有意なシグナルは得られなかった.Transverse momentum distributions of both positive and negative charged particles produced in 200 GeV/ AMU heavy ion collisions are obtained with Magnetic-Interferometric-Emulsitn-Chamber by CERN-EMU05 experiments. The Transverse momentum (P_T) spectra at both central and target rapidity regions showed no anomalous enhancement of low P_T components over a conventional, single exponential function with slope values ranging from 160 to 200 MeV/c. Charge-sign clustering test were tested. G-test were applied for some high multiplicity event. Charge-sign clustering does not exceed that from a random coincidence

Simultaneous distribution between the deflection angle and the lateral displacement under the Molière theory of multiple scattering

Simultaneous distribution between the deflection angle and the lateral displacement of fast charged particles traversing through matter is derived by applying numerical inverse Fourier transforms on the Fourier spectral density solved analytically under the Molière theory of multiple scattering, taking account of ionization loss. Our results show the simultaneous Gaussian distribution at the region of both small deflection angle and lateral displacement, though they show the characteristic contour patterns of probability density specific to the single and the double scatterings at the regions of large deflection angle and/or lateral displacement. The influences of ionization loss on the distribution are also investigated. An exact simultaneous distribution is derived under the fixed energy condition based on a well-known model of screened single scattering, which indicates the limit of validity of the Molière theory applied to the simultaneous distribution. The simultaneous distribution will be valuable for improving the accuracy and the efficiency of experimental analyses and simulation studies relating to charged particle transports

The primary energy spectrum with the Linsley method correcting heavy primary effects in the LAAS experiments

The compact EAS Extensive Air Shower (EAS) array (200 m2) and the Linsley method have been used with the aim to observe the primary energy spectrum. The spectral indexes αproton and αiron are obtained as − 2.46 ± 0.17 and − 3.08 ± 0.24, respectively, in the primary energy region of 1016eV − 1018.5eV in the single observation of the compact EAS array. Additionally, αproton and αiron are obtained as − 3.12 ± 0.13 and − 3.52 ± 0.17, respectively, in the same primary energy region in the observation by restricting the zenith angle of EAS events

Search for large-scale coincidences of EAS in LAAS experiment

Abstract To search for signals from extreme short bursts in the universe, we have performed the large-scale coincidence analysis, using EAS data from five stations of the Large Area Air Shower (LAAS) group. By comparing arrival times and arrival directions of EAS detected at distant stations, coincident and parallel EAS pairs were extracted out of a sea of background cosmic rays. One of them was intriguingly observed from directions consistent with the Crab Nebula, a previously reported UHE γ-ray source. The preliminary results reported here allow the analysis techniques to be tested and demonstrate the potential of observations with the full operation of the network detector system as a cosmic ray interferometer