41 research outputs found
Dirac Mass Matrices in Gauge Field Theory of Horizontal Symmetry
We investigate Dirac mass matrices derived in the gauge field theory of a
horizontal symmetry generated by a central extension of the Pauli algebra.
Through numerical analyses of the observed data of the charged fermion masses
and the flavor mixing matrix of quarks, values of free parameters in the mass
matrices are determined and several empirical relations are found among the
Yukawa coupling constants. As one specific feature of the theory, we find
different orderings in squared mass eigenvalues for the up and down quark
sectors.Comment: 11 pages, 1 figur
Constraints from Unrealistic Vacua in Supersymmetric Standard Model with Neutrino Mass Operators
We analyze a scalar potential of the minimal supersymmetric standard model
(MSSM) with neutrino mass operators along Unbounded-From-Below (UFB) and Color
and/or Charged Breaking (CCB) directions. We show necessary conditions to avoid
the potential minima which can be deeper than the realistic vacuum. These
conditions would constrain more strongly than conditions in the MSSM without
taking into account neutrino mass operators, and can improve the predictive
power of supersymmetric models with neutrino mass operators.Comment: 11 pages, 4 figure
PIV Measurement of a Flying Table Tennis Ball
AbstractThere are some reports that the Magnus force becomes negative at some situation in wind tunnel test. If so, there is possibility of a variety of curves using change of the direction of the Magnus force. PIV measurements of a flying table tennis ball were conducted to confirm whether a similar phenomenon was observed in real flight. A high-speed camera with a frame rate of 10k fps was used to capture the instantaneous flow field of the flying ball. The imaging region was 210mm × 210mm. The Reynolds number was approximately 6.5 × 104, which corresponds to a smash in table tennis. A coordinate transformation of the ball's fixed coordinate system captured the wake motion of non-rotating and rotating balls. In the non-rotating condition, the averaged velocity field of the ball was observed to be symmetric, whereas, in the rotating condition, it was asymmetric, which shows the Magnus effect. At spin parameter is 0.65, the Magnus force becomes zero to indicate the appearance of the negative Magnus force. These observations quantitatively agree with the wind tunnel test
Magneto-optical Imaging Using Polarization Modulation Method
A magneto-optical (MO) microscope that uses the polarization modulation method has been developed for quantitative MO imaging. In this technique, images of MO rotation and ellipticity are reconstructed from three images for different polarization states; i.e., linear, right-circular, and left-circular polarization states. The three polarization states are generated either by rotating a quarter-wave plate or by changing the voltage applied to a liquid crystal modulator (LCM). Measurements are performed using a patterned thin film of Bi,Ga-substituted yttrium iron garnet prepared on a glass substrate. The values of MO rotation and ellipticity obtained from the images for several wavelengths between 450 and 650 nm are found to agree quantitatively with those obtained by an MO spectrometer. Hysteresis loops at any point of the image can be displayed by simply placing a pointer at the position. A real-time MO imaging with a rate of 1 frame/s is also achieved by using the LCM and a high-speed charge-coupled device camera