56081006
MEAN INTERPLANETARY MAGNETIC FIELD MEASUREMENT USING THE ARGO-YBJ EXPERIMENT
The Sun blocks cosmic-ray particles from outside the solar system, forming a detectable shadow in the sky map of cosmic rays detected by the ARGO-YBJ experiment in Tibet. Because the cosmic-ray particles are positively charged, the magnetic field between the Sun and the Earth deflects them from straight trajectories and results in a shift of the shadow from the true location of the Sun. Here, we show that the shift measures the intensity of the field that is transported by the solar wind from the Sun to the Earth.
209869998
Observation of the decay psi(2S) ---> K*(892)anti-K + c.c.
54761229
Energy spectrum of cosmic protons and helium nuclei by a hybrid measurement at 4300 m a.s.l.
The energy spectrum of cosmic Hydrogen and Helium nuclei has been measured below the so-called "knee" by using a hybrid experiment with a wide field-of-view Cherenkov telescope and the Resistive Plate Chamber (RPC) array of the ARGO-YBJ experiment at 4300 m above sea level. The Hydrogen and Helium nuclei have been well separated from other cosmic ray components by using a multi-parameter technique. A highly uniform energy resolution of about 25% is achieved throughout the whole energy range (100–700 TeV). The observed energy spectrum is compatible with a single power law with index γ=−2.63±0.06.
125260045
Evidence of sigma particle in J / psi ---> omega pi pi
124457067
Search for Invisible Decays of eta and eta-prime in the Processes J/psi ---> phi eta and phi eta-prime
Using a data sample of 58x10{sup 6} J/{psi} decays collected with the Beijing Spectrometer II detector at the Beijing Electron Positron Collider, searches for invisible decays of {eta} and {eta}{sup '} in J/{psi} to {phi}{eta} and {phi}{eta}{sup '} are performed. The {phi} signals, which are reconstructed in K{sup +}K{sup -} final states, are used to tag the {eta} and {eta}{sup '} decays. No signals are found for the invisible decays of either {eta} or {eta}{sup '}, and upper limits at the 90% confidence level are determined to be 1.65x10{sup -3} for the ratio (B({eta}{yields}invisible)/B({eta}{yields}{gamma}{gamma})) and 6.69x10{sup -2} for (B({eta}{sup '}{yields}invisible)/B({eta}{sup '}{yields}{gamma}{gamma})). These are the first searches for {eta} and {eta}{sup '} decays into invisible final states.
119348940
Detecting the dark matter annihilation at the ground EAS detectors
Abstract In this paper we study the possibility of detecting gamma rays from dark matter annihilation in the subhalos of the Milky Way by the ground based EAS detectors within the frame of the minimal supersymmetric Standard Model. Based on the Monte Carlo simulation we also study the properties of two specific EAS detectors, the ARGO and HAWC, and the sensitivities of these detectors on the detection of dark matter annihilation. We find the ground EAS detectors have the possibility to observe such signals. Conversely if no signal observed we give the constraints on the supersymmetric parameter space, which however depends on the subhalos properties.
5794968
The Belle trigger system with the new silicon vertex detector SVD2
During the summer shutdown of 2003, the new silicon vertex detector SVD2 was installed in Belle at the KEKB factory and started to take data in October 2003. It provides important improvements in the tracking capabilities and adds new trigger functionality. In addition, a new hardware trigger Level 1.5 was designed and installed that takes advantage of the digitized SVD hit data. The improvement in the Belle trigger system will be important to deal with the increasing luminosity and higher beam currents of the KEKB factory.
119230663
Exact half-BPS string-junction solutions in six-dimensional supergravity
A bstractWe construct SO(2, 1) × SO(3)-invariant half-BPS solutions in six-dimensional (0,4) supergravity with m tensor multiplets. The space-time manifold of each one of these solutions consists of an AdS2 × S2 warped over a Riemann surface Σ with boundary. The most general local solution is parametrized by one real harmonic function, and m + 2 holomorphic functions which are subject to a quadratic constraint and a hermitian inequality, both of which are manifestly SO(2, m) invariant. Imposing suitable conditions on these harmonic and holomorphic functions, we construct globally regular supergravity solutions with N distinct AdS3 × S3 asymptotic regions and contractible Σ. These solutions have an intricate moduli space, whose dimension equals 2(m + 1)N − m − 2 and matches the counting of three-form charge vectors and un-attracted scalars of the tensor multiplet. Exact explicit formulas for all supergravity fields are obtained in terms of the moduli.Our solutions give the near-horizon geometries for junctions of N self-dual strings in six dimensions, and are holographic duals to CFTs defined on N half-planes which share a common interface line. For m = 5, the solutions lift to quarter-BPS solutions for sixdimensional (4,4) supergravity.
123528483
BELLE/SVD2 status and performance
Abstract A new silicon vertex detector for the BELLE experiment was installed and its operation has started successfully at the high-luminosity asymmetric energy e + e - collider KEKB in October 2003. This vertex detector provides a larger polar angle acceptance, a more precise vertex resolution and a better radiation tolerance than the previous one. The obtained performances indicate that the SVD2 works reliably as expected. Moreover, a prospective simulation study shows that the SVD2 should work under the coming higher background conditions.