Equation of state of bismuth to 222 GPa and comparison of gold and platinum pressure scales to 145 GPa

The equation-of-state (EoS) of bcc-bismuth was determined using the Pt pressure scale. Unit cell volumes of Bi, Pt, and Au were also measured simultaneously to megabar pressures by X-ray powder diffraction using a diamond anvil cell and a synchronus radiation source. The results suggest that Au pressure scale gave lower pressure than the Pt pressure scale

Revisiting W gamma production at RHIC

We discuss W gamma production in polarized p p collisions at RHIC energy. We point out that the RHIC collider has two advantages over other hadron colliders to measure the characteristic feature of W gamma production: (1) the RHIC energy is not so high and (2) the polarized beams are available. We calculate the tree level cross section for W gamma production using a generic spin basis for W and discuss both the angular dependence and spin correlation.Comment: 14 pages, 15 Postscript figure

Gauge symmetry reduction from the extra space S-1/Z(2)

We study a mechanism of symmetry transition upon compactification of a 5-dimensional held theory on S-1/Z(2). The transition occurs unless all components in a multiplet of a symmetry group have a common Zz parity on S-1/Z(2). This mechanism is applied to a reduction of SU(5) gauge symmetry in grand unified theory, and phenomenological implications are discussed.ArticlePROGRESS OF THEORETICAL PHYSICS. 103(3):613-619 (2000)journal articl

Misleading Coupling Unification and Lifshitz Type Gauge Theory

We propose a new grand unification scenario for ensuring proton stability. Our scenario is based on the idea that the proton decay problem is an artificial one, which is caused by the identification of the gauge-coupling unification scale with the grand unification scale or the grand unified symmetry breaking scale. We propose a Lifshitz type gauge theory as a candidate for realizing our scenario.ArticlePROGRESS OF THEORETICAL PHYSICS. 122(4):831-845 (2009)journal articl

Triplet-doublet splitting, proton stability and an extra dimension

We propose a new possibility to reconcile the coupling unification scenario with the triplet-doublet mass splitting based on a 5-dimensional supersymmetric model with SU(5) gauge symmetry. It is shown that the minimal supersymmetric standard model is derived on a 4-dimensional wall through compactification on S-1/(Z(2) x Z(2)').ArticlePROGRESS OF THEORETICAL PHYSICS. 105(6):999-1006 (2001)journal articl

Anomalous U(1) D-term Contribution in Type I String Models

We study the $D$-term contribution for anomalous U(1) symmetries in type I string models and derive general formula for the $D$-term contribution, assuming that the dominant source of SUSY breaking is given by $F$-terms of the dilaton, (overall) moduli or twisted moduli fields. On the basis of the formula, we also point out that there are several different features from the case in heterotic string models. The differences originate from the different forms of K\"ahler potential between twisted moduli fields in type I string models and the dilaton field in heterotic string models.Comment: 16 pages, latex, no figur

Vortex-induced topological transition of the bilinear-biquadratic Heisenberg antiferromagnet on the triangular lattice

The ordering of the classical Heisenberg antiferromagnet on the triangular lattice with the the bilinear-biquadratic interaction is studied by Monte Carlo simulations. It is shown that the model exhibits a topological phase transition at a finite-temperature driven by topologically stable vortices, while the spin correlation length remains finite even at and below the transition point. The relevant vortices could be of three different types, depending on the value of the biquadratic coupling. Implications to recent experiments on the triangular antiferromagnet NiGa$_2$S$_4$ is discussed

Re-Analysis of HFT Data Using the Apollo Lunar Surface Gravimeter Data

Introduction: The Apollo Passive Seismic Experiment (PSE) was carried out on Apollo 12, 14, 15 and 16. Network observations of four seismic stations were performed for five years from 1972 to 1977. The PSE was a successful mission that informed us of the lunar crustal thickness and seismic velocity structure of the Moon from direct observations of the lunar interior (e.g. [1]). However, the paucity of seismic stations and the limited number of usable seismic events have been a major problem of lunar seismology. An additional observation point enables us to expand the network and the observable area will expand accordingly. Using a data set called the Work Tape, Kawamura et al. (2008) [2] showed that the Lunar Surface Gravimeter (LSG) on Apollo 17 functioned as a seismograph. With this additional seismic station, we tried the first seismic analysis using the LSG data