The 3He/4He ratio of the new internal He Standard of Japan (HESJ).

Abstract

He ratio of HESJ was determined by obtaining the weighted average of repeated analyses from five machines in four laboratories in Japan. The recommended value of the 3 He/ 4He ratio of HESJ relative to the air value (R/Ra) is 20.63 ± 0.10. HESJ is available to all researchers.

Accurate Measurement of Atmospheric Helium Isotopes

“…If RN-air and RP-air are equal to Rair, as is believed so far, our value of 20.405 ± 0.040Rair agrees well with that of Lupton and Evans,12 but is significantly lower than the recommended value of 20.63 ± 0.10Rair. Taking into account the compilations by Matsuda et al, 15 one may realize that the HESJ values of Laboratory for Earthquake Chemistry and Earthquake Research Institute, the University of Tokyo are significantly higher than the other results (Table 1). These air standards were collected on the main campus of the University of Tokyo.…”

“…Matsuda et al 15 thus prepared He Standard of Japan (HESJ) with a relatively high 3 He/ 4 He ratio. They submitted a split of HESJ in a gas cylinder to four laboratories in Japan, and asked them to measure the 3 He/ 4 He ratio calibrated against the air standard in each laboratory (Table 1).…”

“…They submitted a split of HESJ in a gas cylinder to four laboratories in Japan, and asked them to measure the 3 He/ 4 He ratio calibrated against the air standard in each laboratory (Table 1). Based on the six independent analyses, the recommended value of 20.63 ± 0.10Rair was presented by Matsuda et al 15 We collected air samples at a small park close to our campus in Nakano, Tokyo. Figure 3 shows the reproducibility of a single air sample collected at Nakano measured by the Helix mass spectrometer within seven successive days.…”

“…It is noted that the mass resolving powers of both collectors have increased significantly compared with those of the old system, 550 for the Daly detector and 200 for the Faraday cup. We used a new internal helium standard (HESJ) prepared by Matsuda et al 15 as a running standard to calibrate the sample 3 He/ 4 He ratio. A known amount of HESJ, 2.0 × 10 -7 ccSTP was admitted into the highprecision noble-gas mass spectrometer, and the sensitivity of helium was assessed.…”

Origin and fate of deep-sea seeping methane bubbles at Kuroshima Knoll, Ryukyu forearc region, Japan

“…through conventional methods (Sakai et al, 1976). The helium and neon contents and 3 He/ 4 He ratio in the gas samples were measured with a modified-VG5400 (MS-III) noble gas mass spectrometer in the University of Tokyo with an accuracy better than 4%, following the procedure described by Aka et al (2001), except for using the interlaboratory helium standard (HESJ, Matsuda et al, 2002) for the standard material of the 3 He/ 4 He ratio.…”