Thermally altered subsurface material of asteroid (162173) Ryugu

Kitazato, Kohei*; Milliken, R. E.*; Iwata, Takahiro*; Abe, Masanao*; Otake, Makiko*; Matsuura, Shuji*; Takagi, Yasuhiko*; Nakamura, Tomoki*; Hiroi, Takahiro*; Matsuoka, Moe*; et al.

Nature Astronomy (Internet), 5(3), p.246 - 250, 2021/03

https://doi.org/10.1038/s41550-020-01271-2

Here we report observations of Ryugu's subsurface material by the Near-Infrared Spectrometer (NIRS3) on the Hayabusa2 spacecraft. Reflectance spectra of excavated material exhibit a hydroxyl (OH) absorption feature that is slightly stronger and peak-shifted compared with that observed for the surface, indicating that space weathering and/or radiative heating have caused subtle spectral changes in the uppermost surface. However, the strength and shape of the OH feature still suggests that the subsurface material experienced heating above 300 C, similar to the surface. In contrast, thermophysical modeling indicates that radiative heating does not increase the temperature above 200 C at the estimated excavation depth of 1 m, even if the semimajor axis is reduced to 0.344 au. This supports the hypothesis that primary thermal alteration occurred due to radiogenic and/or impact heating on Ryugu's parent body.

The Characteristics of radiation-induced cell responses in the canine spontaneous tumor cells

Sano, Tadashi*; Wada, Seiichi*; Suzuki, Keiko*; Natsuhori, Masahiro*; Kakizaki, Takehiko; Ito, Takashi*; Nakazawa, Konomi*; Kobayashi, Yasuhiko; Ito, Nobuhiko*

JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 115, 2007/02

https://jopss.jaea.go.jp/pdfdata/JAEA-Review-2006-042.pdf

Inner-shell ionization in high density hot plasma produced by high intensity laser irradiation

Moribayashi, Kengo; Zhidkov, A. J.*; Sasaki, Akira; Sudo, Keiko; Suzuki, Shingo*

Atomic Collision Research in Japan, No.27, p.1 - 3, 2001/00

no abstracts in English

Practical research using the spontaneous neoplasm case of the dog as a particle irradiation treatment model

Sano, Tadashi*; Suzuki, Keiko*; Natsuhori, Masahiro*; Kakizaki, Takehiko; Ito, Nao*; Nakazawa, Konomi*; Ito, Nobuhiko*; Wada, Seiichi*; Kobayashi, Yasuhiko

no journal, , 

no abstracts in English

Exposure of normal human diploid fibroblasts to heavy ions accelerate differentiation in their progeny

Sora, Sakura; Hamada, Nobuyuki*; Hara, Takamitsu*; Funayama, Tomoo; Sakashita, Tetsuya; Kataoka, Keiko*; Suzuki, Michiyo; Fukamoto, Kana; Yokota, Yuichiro; Kobayashi, Yasuhiko

no journal, , 

no abstracts in English

Effects of -ray irradiation on the basal slowing response in

Suzuki, Michiyo; Sakashita, Tetsuya; Funayama, Tomoo; Fukamoto, Kana; Hamada, Nobuyuki*; Yokota, Yuichiro; Kataoka, Keiko*; Sora, Sakura; Tsuji, Toshio*; Kobayashi, Yasuhiko

no journal, , 

no abstracts in English

Update of database for element-specific parameters in biosphere assessment of geological disposal

Kato, Tomoko; Suzuki, Yuji*; Tagami, Keiko*; Ishikawa, Nao*; Uchida, Shigeo*; Inagaki, Manabu; Miyahara, Kaname

no journal, , 

To select and to presume the parameters adaptable to biosphere assessment of geological disposal at an actual environment, the procedure of updating a database using the domestic biosphere data was developed and was tried to a part of element-specific parameters. As a result, we were able to set the reliable biosphere parameters, by arranging important background information to secure the reliability of the parameter.

Preliminary study on an analysis method of rare earths and others in spent fuel using an anion exchange resin

Sato, Makoto; Fukaya, Hiroyuki; Umeda, Miki; Suyama, Kenya; Tonoike, Kotaro; Kamohara, Keiko*; Suzuki, Norihisa*

no journal, , 

no abstracts in English

Study on Sm/Pm separation for spent fuel composition analysis

Sato, Makoto; Ichimura, Seiji; Suyama, Kenya; Tonoike, Kotaro; Kamohara, Keiko*; Suzuki, Norihisa*

no journal, , 

no abstracts in English