Mesospheric ionization during substorm growth phase

Murase, Kiyoka*; Kataoka, Ryuho*; Nishiyama, Takanori*; Nishimura, Koji*; Hashimoto, Taishi*; Tanaka, Yoshimasa*; Kadokura, Akira*; Tomikawa, Yoshihiro*; Tsutsumi, Masaki*; Ogawa, Yasunobu*; et al.

Journal of Space Weather and Space Climate (Internet), 12, p.18_1 - 18_16, 2022/06

https://doi.org/10.1051/swsc/2022012

We identified two energetic electron precipitation (EEP) events during the growth phase of moderate substorms and estimated the mesospheric ionization rate for an EEP event for which the most comprehensive dataset from ground-based and space-born instruments was available. The mesospheric ionization signature reached below 70 km altitude and continued for ~15 min until the substorm onset, as observed by the PANSY radar and imaging riometer at Syowa Station in the Antarctic region. We also used energetic electron flux observed by the Arase and POES 15 satellites as the input for the air-shower simulation code PHITS to quantitatively estimate the mesospheric ionization rate. Combining the cutting-edge observations and simulations, we shed new light on the space weather impact of the EEP events during geomagnetically quiet times, which is important to understand the possible link between the space environment and climate.

Proposal of healthiness confirmation procedure in electro manometer system in terms of nuclear material accountancy

Shoji, Kaoru; Mukai, Yasunobu; Nakamura, Hironobu; Yoshimoto, Katsunobu; Hayashi, Hiroyuki*

Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-32-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2011/11

In general, electro manometer system for volume measurement in high concentrated Pu, U solution is used. The measurement uncertainty of volume measurement should be kept within 0.36% in the nuclear material accountancy. Not only manometer censors are calibrated periodically, but also operator should maintain the integrity of entire volume measurement system. If clogging at a tip of dip-tube is occurred, it causes measurement bias. Therefore, we studied confirmation procedure of healthiness in the system during solution storage. As result, it is confirmed that following points are effective: (1) Confirmation of consistency in the Kumar's density formula by using actual Pu, U concentration, density and acidity determined by periodical sampling and high accuracy DA. In addition, Pu, U mass is maintained within the uncertainty from the previous sampling/DA result. (2) In order to confirm the integrity of differential pressure for density that may be impacted regarding the measurement bias by clogging, comparison between measured differential pressure for density and analyzed density with high accuracy is important. In the confirmation for density, correction method between different temperatures was established by the result of evaluation of temperature effect derived by Kumar's density formula.

The First loading fuel elements and power-up for JRR-2

JRR-2 Control Office; Kambara, Toyozo; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Kohayakawa, Toru; Morozumi, Minoru; Kambayashi, Yuichiro; Shitomi, Hajimu; Kokanezawa, Takashi; et al.

JAERI 1027, 57 Pages, 1962/09

JAERI-1027.pdf:4.76MB

no abstracts in English

Treatment and analysis of the water and gas in JRR-2

JRR-2 Operations Office; Kambara, Toyozo; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Haginoya, Kinichi; Kohayakawa, Toru; Yamaki, Jikei; Yokota, Mitsuo; Horiki, Oichiro; et al.

JAERI 1024, 79 Pages, 1962/08

JAERI-1024.pdf:5.66MB

no abstracts in English

MOX conversion test for fugen MOX spent fuel, 2; Temperature evaluation for MOX powder

Fujisaku, Sakae; Nakamura, Hironobu; Takaya, Akikazu; Nakamichi, Hideo; Matsumoto, Masaki; Shoji, Kaoru*; Yoshimoto, Katsunobu

no journal, , 

For the MOX conversion test by using plutonium nitrate solution that is recovered by Fugen MOX spent fuel, JAEA had perform the temperature evaluation for MOX powder and had established the guideline for thermal effect by comparing measured temperature with designed temperature.

MOX conversion test for Fugen MOX spent fuel, 1; Temperature evaluation for plutonium nitrate storage tank

Nakamura, Hironobu; Nakamichi, Hideo; Takaya, Akikazu; Shoji, Kaoru*; Matsumoto, Masaki; Fujisaku, Sakae; Yoshimoto, Katsunobu

no journal, , 

For the MOX conversion test by using plutonium nitrate solution that is recycled by Fugen MOX spent fuel, JAEA had performed temperature evaluation for plutonium solution receiving tank (annular shape), and had established the guideline of thermal effect by comparing the measured temperature with designed temperature.