S Hara

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Protons with energies up to approximately 10(15) eV are the main component of cosmic rays, but evidence for the specific locations where they could have been accelerated to these energies has been lacking. Electrons are known to be accelerated to cosmic-ray energies in supernova remnants, and the shock waves associated with such remnants, when they hit the(More)
This paper reports the first discovery of TeV gamma-ray emission from a supernova remnant made with the CANGAROO 3.8 m Telescope. TeV gamma rays were detected at the sky position and extension coincident with the northeast (NE) rim of shell-type Supernova remnant (SNR) SN1006 (Type Ia). SN1006 has been a most likely candidate for an extended TeV Gamma-ray(More)
The nature of post-ictal headache (PIH) remains unclear. A multicenter study was conducted in order to evaluate frequency and risk factors for PIH. The subjects consisted of 97 patients with temporal lobe epilepsy (TLE), 65 patients with frontal lobe epilepsy (FLE) and 37 patients with occipital lobe epilepsy (OLE). The subjects were asked about PIH at each(More)
We report on the status of the construction of an array of four 10 m atmospheric Cherenkov telescopes for gamma-ray astronomy, near Woomera, in South Australia – the CANGAROO-III project. The first telescope of this array is the upgraded version of the CANGAROO-II 7 m telescope and has been in operation since March 2000. The second telescope, an improved(More)
CANGAROO group has constructed the new large imaging Aiř Cerenkov telescope to exploit hundred GeV region gamma-ray astronomy in March 1999 at Woomera, South Australia. It has a 7m parabolic mirror consisting of 60 small plastic spherical mirrors, and a fine imaging camera with 512 PMTs covering the field of view of 3 degree. Observation will start from(More)
A 7/10 m diameter Cerenkov telescope of the CANGAROO II project will start operation in 1999 in Woomera, South Australia, with a 7 m aperture using 60 plastic mirrors. The telescope aims to observe 100 GeV gamma-ray sources in the southern sky. Table 1 Characteristics of the CANGAROO 7/10 m telescope. Mirror Type Composite Shape of the frame Parabolic Focal(More)
CANGAROO-III is an array of four 10m-diameter imaging atmospheric Cherenkov telescopes to search for sub-TeV gamma-rays from celestial objects in collaboration with Japanese and Australian institutions, which is located in southern hemisphere (Woomera, South Australia). Three of four telescopes were made with the same design for stereo observation. We have(More)
We have detected gamma-ray emission at the 6 σ level at energies greater than 500 GeV from the supernova remnant RX J0852.0−4622 (G266.2−1.2) using the – 2 – CANGAROO-II Imaging Atmospheric Cherenkov Telescope (IACT). The flux was 0.12 times of that of Crab at 1 TeV. The signal centroid is consistent with the peak of the X-ray emission in the northwest rim(More)
A preliminary result from Markarian 421 observations in the energy region above 10 TeV with the CANGAROO-II 10 m telescope is presented. In January 2001, the HEGRA group reported that Markarian 421 had become very active, with flux levels up to 4 times that of the Crab Nebula. As a result, we observed Mkn 421 during six nights from Jan-uary 24th to February(More)
BACKGROUND AND PURPOSE Arterial spin-labeling MR imaging with multiple postlabeling delays has a potential to evaluate various hemodynamic parameters. To clarify whether arterial spin-labeling MR imaging can identify CBF and perfusion delay in patients with Moyamoya disease, we compared arterial spin-labeling, DSC, and 15O-gas PET in terms of their ability(More)