How many electrons are needed to flip a local spin?

Considering the spin of a local magnetic atom as a quantum mechanical operator, we illustrate the dynamics of a local spin interacting with a ballistic electron represented by a wave packet. This approach improves the semi-classical approximation and provides a complete quantum mechanical understanding for spin transfer phenomena. Sending spin-polarized electrons towards a local magnetic atom one after another, we estimate the minimum number of electrons needed to flip a local spin.Comment: 3 figure

Analysis of atmospheric neutrino oscillations in three-flavor neutrinos

We analyze the atmospheric neutrino experiments of Super-Kamiokande (830-920 live days) using the three-flavor neutrino framework with the mass hierarchy m_1 nearly equal m_2 << m_3. We study the sub-GeV, multi- GeV neutrinos and upward through-going and stopping muons zenith angle distributions taking account of the Earth matter effects thoroughly. We obtain the allowed regions of mass and mixing parameters Delm^2_{23}, theta_{13} and theta_{23}. Delm^2_{23} is restricted to 0.002-0.01eV^2 and theta_{13}<13degrees, 35degrees<theta_{23}<55degrees in 90% C.L. For theta_{12}, there is no difference between the large angle solar neutrino solution and small one. From chi^2 fit, the minimum chi^2=55(54DOF) is obtained at Delm^2_{23}=4x10^(-3)eV^2, theta_{13}=10degrees and theta_{23} =45degrees.Comment: 16 pages, 3 figures, LaTe

Flavor Mass and Mixing and S_3 Symmetry -- An S_3 Invariant Model Reasonable to All --

We assume that weak bases of flavors (u, c)_{L,R}, (d,s)_{L,R}, (e, \mu) _{L,R}, (\nu_e, \nu_\mu)_{L,R} are the S_3 doublet and t_{L,R}, b_{L,R}, \tau_{L,R}, {\nu_\tau}_{L,R} are the S_3 singlet and further there are S_3 doublet Higgs (H_D^1, H_D^2) and S_3 singlet Higgs H_S. We suggest an S_3 invariant Yukawa interaction, in which masses caused from the interaction of S_3 singlet flavors and Higgs is very large and masses caused from interactions of S_3 doublet flavors and Higgs are very small, and the vacuum expectation value _0 is rather small compared to the _0. In this model, we can explain the quark sector mass hierarchy, flavor mixing V_{CKM} and measure of CP violation naturally. The leptonic sector mass hierarchy and flavor mixing described by V_{MNS} having one-maximal and one-large mixing character can also be explained naturally with no other symmetry restriction. In our model, an origin of Cabibbo angle is the ratio \lambda=_0 /_0 and an origin of CP violation is the phase of H_D^1.Comment: 16 page

A simulation of high energy cosmic ray propagation 1

High energy cosmic ray propagation of the energy region 10 to the 14.5 power - 10 to the 18th power eV is simulated in the inter steller circumstances. In conclusion, the diffusion process by turbulent magnetic fields is classified into several regions by ratio of the gyro-radius and the scale of turbulence. When the ratio becomes larger then 10 to the minus 0.5 power, the analysis with the assumption of point scattering can be applied with the mean free path E sup 2. However, when the ratio is smaller than 10 to the minus 0.5 power, we need a more complicated analysis or simulation. Assuming the turbulence scale of magnetic fields of the Galaxy is 10-30pc and the mean magnetic field strength is 3 micro gauss, the energy of cosmic ray with that gyro-radius is about 10 to the 16.5 power eV

Effects to Scalar Meson Decays of Strong Mixing between Low and High Mass Scalar Mesons

We analyze the mass spectroscopy of low and high mass scalar mesons and get the result that the coupling strengths of the mixing between low and high mass scalar mesons are very strong and the strengths of mixing for $I=1, 1/2$ scalar mesons and those of I=0 scalar mesons are almost same. Next, we analyze the decay widths and decay ratios of these mesons and get the results that the coupling constants $A'$ for $I=1, 1/2$ which represents the coupling of high mass scalar meson $N'$ -> two pseudoscalar mesons $PP$ are almost same as the coupling $A'$ for the I=0. On the other hand, the coupling constant $A$ for $I=1, I=1/2$ which represents the low mass scalar meson $N$ -> $PP$ are far from the coupling constant $A$ for I=0. We consider a resolution for this discrepancy. Coupling constant $A''$ for glueball $G$ -> $PP$ is smaller than the coupling $A'$. $\theta_P$ is $40^\circ \sim 50^\circ$.Comment: 15 pages, 6 figure

Mixing among light scalar mesons and L=1 q\bar{q} scalar mesons

Following the re-establishment of the \sigma(600) and the \kappa(900), the light scalar mesons a_0(980) and f_0(980) together with the \sigma(600) and the \kappa(900) are considered as the chiral scalar partner of pseudoscalar nonet in SU(3) chiral symmetry, and the high mass scalar mesons a_0(1450), K^*_0(1430), f_0(1370) and f_0(1710) turned out to be considered as the L=1 q\bar{q} scalar mesons. We assume that the high mass of the L=1 q\bar{q} scalar mesons is caused by the mixing with the light scalar mesons. For the structure of the light scalar mesons, we adopted the qq\bar{q}\bar{q} model in order to explain the "scalar meson puzzle". The inter-mixing between the light scalar nonet and the high mass L=1 q\bar{q} nonet and the intra-mixing among each nonet are analyzed by including the glueball into the high mass scalar nonet.Comment: 16 pages, 5 figure

Measurement of energy muons in EAS at energy region larger thean 10(17) eV

A measurement of low energy muons in extensive air showers (EAS) (threshold energies are 0.25, 0.5, 0.75 and 1.38 GeV) was carried out. The density under the concrete shielding equivalent to 0.25 GeV at core distance less than 500 m and 0.5 GeV less than 150 m suffers contamination of electromagnetic components. Therefore the thickness of concrete shielding for muon detectors for the giant air shower array is determined to be 0.5 GeV equivalence. Effects of photoproduced muons are found to be negligible in the examined ranges of shower sizes and core distances. The fluctuation of the muon density in 90 sq m is at most 25% between 200 m and 600 m from the core around 10 to the 17th power eV