Yoshimi Matsubara

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– 2 – Observations of the PSR B1259−63/SS2883 binary system using the CANGAROO-II Cherenkov telescope are reported. This nearby binary consists of a 48 msec radio pulsar in a highly eccentric orbit around a Be star, and offers a unique laboratory to investigate the interactions between the outflows of the pul-sar and Be star at various distances. It has(More)
We present the discovery of a Neptune-mass planet OGLE-2007-BLG-368Lb with a planet–star mass ratio of q = [9.5 ± 2.1] × 10 −5 via gravitational microlensing. The planetary deviation was detected in real-time thanks to the high cadence of the Microlensing Observations in Astrophysics survey, real-time light-curve monitoring and intensive follow-up(More)
We describe observations carried out by the MOA group of the Galactic Bulge during 2000 that were designed to detect efficiently gravitational microlensing of faint stars in which the magnification is high and/or of short duration. These events are particularly useful for studies of extra-solar planets and faint stars. Approximately 17 deg 2 were monitored(More)
The CANGAROO-III project, which consists of an array of four 10 m imaging Cherenkov telescopes, has just started being constructed in Woomera, South Australia, in a collaboration between Australia and Japan. The first stereoscopic observation of celestial high-energy gamma-rays in the 100 GeV region with two telescopes will start in 2002, and the four(More)
The disorder parameter of confinement-deconfinement phase transition based on the monopole action determined previously in SU (2) QCD are investigated. We construct an operator which corresponds to the order parameter defined in the abelian Higgs model. The operator shows proper behaviors as the disorder parameter in the numerical simulations of finite(More)
We report the results of TeV gamma-ray observations of the shell type SNR RX J1713.7?3946 (G347.3?0.5). The discovery of strong non-thermal X-ray emission from the northwest part of the remnant strongly suggests the existence of electrons with energies up to 100 TeV in the remnant, making the SNR a good candidate TeV gamma-ray source. We observed RX(More)
Effective monopole actions for various extended monopoles are derived from vacuum configurations after abelian projection in the maximally abelian gauge in T = 0 and T = 0 SU (3) lattice QCD. The actions obtained appear to be independent of the lattice volume adopted. At zero temperature, monopole condensation is seen to occur from energy-entropy balance in(More)
Introduction: When fluvial erosion was active during the Noachian, creation and integration of drainage networks competed with disruption by impacts. As a result, drainage networks were composed of valley networks interspersed with crater and intercrater basins which would have overflowed only if contributing basin size and rainfall amounts exceeded(More)