Nov 26 – 27, 2020
RIKEN Wako Campus
Asia/Tokyo timezone

Estimation of Flux and Residual Radioactivity for the COMET Phase-I Experiment / COMET Phase-I実験のための粒子線束と残留放射能の評価

Nov 26, 2020, 5:11 PM
1h 39m
RIBF201 (RIKEN Wako Campus)

RIBF201

RIKEN Wako Campus

Hirosawa 2-1, Wako City, Saitama 351-0198, Japan
Poster Presentation Poster

Speaker

Naoki / 直輝 Tokunaga / 徳永 (Kyushu University / 九州大学)

Description

COherent Muon to Electron Transition (COMET) is an experiment at J-PARC, which will search for coherent neutrino-less conversion of a muon to an electron in muonic atoms. The experiment will be carried out in two steps: Phase-I and Phase-II. In the Phase-I experiment, 3.2 kW 8 GeV proton beam irradiates a 70-cm long graphite target to produce negative pions. The negative pions are captured in the magnetic field and delivered to pion-decay and muon-transport sections. The Phase-I experiment aims to detect the $\mu^-e$ conversion events and measure the beam-related background events for the Phase-II experiment. Now, it has been planned that the maintenance by radiation workers would be conducted after the 150-day operation and the following 180-day cooling. It is necessary to evaluate the residual radiation dose for the safety of the workers during the maintenance. On this study, we calculated fluxes of neutron, photon, proton and other charged particles in the beam room during the beam operation and the residual activity after the cooling time by using Monte Carlo simulation code PHITS version 3.22 and DCHAIN-PHITS version 3.21. The calculation results show that the design of components around the target and beam dump needs to be improved to reduce the radioactivities after the cooling time.

Primary author

Naoki / 直輝 Tokunaga / 徳永 (Kyushu University / 九州大学)

Co-authors

Nobuhiro / 信寛 Shigyo / 執行 (Kyushu University / 九州大学) Shunsuke / 俊助 Makimura / 牧村 (Institute of Particle and Nuclear Studies J-PARC Center Particle and Nuclear Physics Division Hadron Section Tokai campus / 素粒子原子核研究所 J-PARCセンター 素粒子原子核ディビジョン ハドロンセクション 東海キャンパス) Yoshinori / 祥紀 Fukao / 深尾 (Institute of Particle and Nuclear Studies J-PARC Center Particle and Nuclear Physics Division Hadron Section Tokai campus / 素粒子原子核研究所 J-PARCセンター 素粒子原子核ディビジョン ハドロンセクション 東海キャンパス) Naoya / 直矢 Kamei / 亀井 (Institute of Particle and Nuclear Studies J-PARC Center Particle and Nuclear Physics Division Hadron Section Tokai campus / 素粒子原子核研究所 J-PARCセンター 素粒子原子核ディビジョン ハドロンセクション 東海キャンパス) Makoto / 誠 Yoshida / 吉田 (J-PARC Center, High Energy Accelerator Research Organization (KEK) / 高エネルギー加速器研究機構 J-PARCセンター)

Presentation materials

Peer reviewing

Paper