64774799
Preliminary results of the Moon shadow using ARGO-YBJ detector
ARGO-YBJ is a “full coverage” air shower detector consisting of Resistive Plate Chambers(RPCs) at the Yangbajing High Altitude Cosmic Ray Laboratory (Tibet, China) at 4300 m a.s.l. (lat=30.11° N, long=90.53° E). Using the data collected with a carpet of RPCs (1900 m 2 , about 1/3 of the whole ARGO-YBJ detector), the cosmic ray shadowing effect due to the Moon was studied. The 50% angular resolution is found to be ∼1.2° with the Chess-board method and the Moon shadow with a significance of 4.9 σ is found displaced by 0.7° westward and 0.5° northward with respect to the expected position by the equi-zenith angle Method.
16935677
Layout and performance of RPCs used in the Argo-YBJ experiment
The layout of the RPCs, used in the Argo-YBJ experiment to image with a high space-time granularity the atmospheric shower, is described in this paper. The detector has been assembled to provide both digital and analog informations in order to cover a wide particle e front matter r 2006 Elsevier B.V. All rights reserved. ma.2006.02.136 ing author. Tel.: +306 55177285; fax: +30 6 55177207. ess: mari@fis.uniroma3.it (S.M. Mari). ess: Dipartimento di Fisica dell’Università di Genova and INFN Sezione di Genova, Italy.
117769487
Special Theory for Superluminal Particle
The OPERA collaboration reported evidence for muonic neutrinos travelling faster than light in vacuum. In this paper, an extended relativity theory is proposed. We think all particles can be divided into three kinds: The first kind of particle is its velocity in the range of $0\leq v < c$, e.g. electron, atom, molecule and so on ($c$ is light velocity, i.e., the limit velocity of the first kind of particle). The second kind of particle is its velocity in the range of $0\leq v < c_{m1}$, e.g. photon ($c_{m1}$ is the limit velocity of the second kind of particle). The third kind of particle is its velocity in the range of $c\leq v < c_{m2}$, e.g. tachyon, and muonic neutrinos ($c_{m2}$ is the limit velocity of the third kind of particle). The first kind of particle is described by the special relativity. With the extended relativity theory, we can describe the second and third kinds particles, and can analysis the OPERA experiment results and calculate the muonic neutrinos mass.
119208520
Testing the consistency of Gamma Ray Burst data-set and Supernovae Union2
In this paper, we test the consistency of Gamma Ray Bursts (GRBs) Data-set and Supernovae Union2 (SNU2) via the so-called multi-dimensional consistency test under the assumption that ΛCDM model is a potentially correct cosmological model. We find that the probes are inconsistent with 1.456σ and 85.47% in terms of probability. With this observation, it is concluded that GRBs can be combined with SNU2 to constrain cosmological models.
110151526
Linearity analysis for position sensitive detectors using finite element method
Abstract A Finite Element Method (FEM) to simulate and analyze position-sensitive detector (PSD) is presented in this paper. A computational model and analytical method for PSD is proposed. For example, two types of PSD with additional resistive bordered, i.e., pin-cushion PSD and square-bordered PSD, are simulated. The relationships among the structural parameters, electrical parameters and the position linearity performance of these two PSD are investigated. In addition, the load impedance effect is analyzed. The results are consistent with other researchers’ experimental results.
121568193
Energy determination at BEPC-II
The BEPC-II collider beam energy calibration system is discussed. The system is based on the Compton backscattering method. The expected precision of the electron and positron beam energy e determination is δ e / e ≈ 3 ⋅ 10 − 5 .
53989444
The Status of the ARGO Experiment at YBJ
The ARGO-YBJ experiment, located at Yangbajing, Tibet, China, performed by a wide Sino-Italian collaboration, is designed to study cosmic rays, sub-TeV gamma ray sources and GeV Gamma Ray Burst (GRB) emission in the northern hemisphere, by means of detecting small size EAS (Extensive Air Shower) using a full coverage RPC (Resistive Plate Chamber) carpet. The central carpet of the detector is installed and put into operation to date, with 1900m2 of the carpet already operating since December 2004. With a trigger multiplicity of ≥60 hits, corresponding to a primary mode energy of 2 TeV, the angular resolution of EAS measurements is