Takahisa Yamamoto

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During the 6 th August 1995, the CUTLASS Finland HF radar ran in a high time resolution mode, allowing measurements of line-of-sight convection velocities along a single beam with a temporal resolution of 14 s. Data from such scans, during the substorm expansion phase, revealed pulses of equatorward ¯ow exceeding $600 m s A1 with a duration of $5 min and a(More)
We present multipoint observations of a series of bursty bulk flow events (BBFs) observed by WIND and GEOTAIL positioned in roughly the same local time sector in the magnetotail. Simultaneous IMP8 measurements from the solar wind showed significant amounts of energy coupling into the magnetosphere while the ultraviolet imager (UVI) on POLAR evidenced the(More)
Bias-induced oxygen ion dynamics underpins a broad spectrum of electroresistive and memristive phenomena in oxide materials. Although widely studied by device-level and local voltage-current spectroscopies, the relationship between electroresistive phenomena, local electrochemical behaviors, and microstructures remains elusive. Here, the interplay between(More)
An in situ optical absorbance technique was used to monitor the growth of vertically aligned single-walled carbon nanotubes (VA-SWNTs) at various temperatures and pressures. The effects of the growth temperature and ethanol pressure on the initial growth rate and catalyst lifetime were investigated. It was found that the ideal pressure for VA-SWNT synthesis(More)
Geotail energetic particle, magnetic ®eld data and plasma observations (EPIC, MGF and CPI experiments) have been examined for a number of energetic particle bursts in the distant tail …120Rè jX GSM j ` 130 Re†, associated with moving magnetic ®eld structures , following substorm onsets. The features obtained from this data analysis are consistent with the(More)
Simultaneous energetic particle and magnetic ®eld observations from the GEOTAIL spacecraft in the distant tail (X GSM % A150 Re) have been analysed to study the response of the Earth's magnetotail during a strong substorm (AE 680 nT). At geosynchronous altitude, LANL spacecraft recorded three electron injections between 0030 UT and 0130 UT, which correspond(More)
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