@article{oai:repo.qst.go.jp:00081107,
 author = {Sumida, Shuhei and Shinohara, Koji and Nishitani, Takeo and Ogawa, Kunihiro and Bando, Takahiro and Sukegawa, Atsuhiko and Ishikawa, Masao and Takada, Eiji and Bierwage, Andreas and Oyama, Naoyuki and Shuhei, Sumida and Koji, Shinohara and Takahiro, Bando and Atsuhiko, Sukegawa and Masao, Ishikawa and Bierwage, Andreas and Naoyuki, Oyama},
 issue = {11},
 journal = {Review of Scientific Instruments},
 month = {Nov},
 note = {Materials and structures of a collimator for a new neutron emission profile monitor in JT-60SA are examined through Monte-Carlo simulations using the Monte Carlo N-Particle transport code. First, the shielding properties of various material combinations are compared in order to determine a combination with high shielding performances against both neutrons and gamma-rays. It is found that a collimator consisting of borated polyethylene and lead has a high shielding performance against neutrons. Moreover, a high shielding performance against gamma-rays is obtained when a lead pipe with a radial thickness of 0.01 m is inserted into a collimation tube. Second, we demonstrate that it is possible to improve the spatial resolution to the desired level by installing a thin tubular extension structure that fits into the limited space available between the main collimator block and the tokamak device. Finally, the collimator structures that meet both the targeted spatial resolutions (< 10% of the plasma minor radius) and the targeted counting rate (105 cps order) are discussed.},
 pages = {113504-1--113504-12},
 title = {Conceptual Design of a Collimator for the Neutron Emission Profile Monitor in JT-60SA Using Monte-Carlo Simulations},
 volume = {91},
 year = {2020}
}