Spectroscopic Measurements of L X-rays with a TES Microcalorimeter for a Non-destructive Assay of Transuranium Elements. - Nakamura, Keisuke; Morishita, Yuki; Takasaki, Koji; Maehata, Keisuke; Sugimoto, Tetsuya; Kiguchi, Yu; Iyomoto, Naoko; Mitsuda, Kazuhisa (Journal of Low Temperature Physics, 2018)