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Kreinder, B.; Cox, I.*; Grzywacz, R.*; 西尾 勝久; 他24名*
Nuclear Instruments and Methods in Physics Research A, 1085, p.171298_1 - 171298_7, 2026/05
被引用回数：0 パーセンタイル：0.00(Instruments & Instrumentation)In recent experiments, inorganic scintillators have been used to study the decays of exotic nuclei, providing an alternative to silicon detectors and enabling measurements that were previously impossible. However, proper use of these materials requires us to understand and quantify the scintillation process, specifically in response to very heavy nuclei. In this work, we show a simplified method based on the models of Birks (1951) and Meyer and Murray (1962) to parametrize the light output of inorganic scintillators in response to beams of energetic heavy ions over a broad range of energies. We test the accuracy of our parametrization approach by calculating light output and quenching factors for various ions and comparing them with experimental data from Lutetium Yttrium Orthosilicate (LYSO:Ce), a common inorganic scintillator. The Meyer-Murray model suggests that, for sufficiently heavy ions at high energies, the majority of the light output is associated with the creation of delta electrons, which are induced by the passage of the beam through the material. These delta electrons dramatically impact the response of detection systems when subject to ions with velocities typical of beams in modern fragmentation facilities. To illustrate this, we also present a qualitative estimate of the effects of delta rays on overall light output using the Birks-Meyer-Murray parametrization. The approach presented herein will serve as a basic framework for further, more rigorous studies of scintillator response to heavy ions. This work is a crucial first step in planning future experiments where energetic exotic nuclei are interacting with scintillator detectors.
Rosenbusch, M.*; 伊藤 由太; 他24名*
Nuclear Instruments and Methods in Physics Research A, 1047, p.167824_1 - 167824_12, 2023/02
被引用回数：30 パーセンタイル：96.51(Instruments & Instrumentation)理化学研究所RIBFのZeroDegreeスペクトロメーター後方に新しい多重反射型飛行時間測定質量分析装置を設置した。パルスドリフトチューブ技術を用いてイオンの運動エネルギーを広範囲に変化させることで、システムの分散関数を直接的に評価し、静電ミラーに印加する電圧を最適化した。これにより、わずか12.5ミリ秒の全飛行時間で10
の質量分解能を達成し、短寿命低エネルギー核異性体の研究を可能にした。
Chiaveri, E.*; Aberle, O.*; Alcayne, V.*; 木村 敦; 他124名*
EPJ Web of Conferences, 239, p.17001_1 - 17001_8, 2020/09
被引用回数：7 パーセンタイル：95.61(Nuclear Science & Technology)Since the start of its operation in 2001, the neutron time of-flight facility of CERN, n_TOF, has become one of the most forefront neutron facilities in the world for wide-energy spectrum neutron cross section measurements. Thanks to the combination of excellent neutron energy resolution and high instantaneous neutron flux available in the two experimental areas, the second of which has been constructed in 2014, n_TOF is providing a wealth of new data on neutron-induced reactions of interest for nuclear astrophysics, advanced nuclear technologies and medical applications. In this document the main characteristics of the n_TOF facility and their relevance for neutron studies in the different areas of research will be outlined. In addition, the future perspectives of the facility will be described including the upgrade of the spallation target, the setup of an imaging installation and the construction of a new irradiation area.
小松 雄哉*; 市川 裕大; 成木 恵*; 谷田 聖; 他24名*
JPS Conference Proceedings (Internet), 26, p.022029_1 - 022029_4, 2019/11
A di-quark correlation has been proposed to describe the internal structure of hadrons, especially those of exotic ones. Nevertheless it lacks a conclusive experimental evidence. The J-PARC E50 experiment performs charmed baryon spectroscopy at J-PARC high-momentum beam line to investigate the role of di-quark correlations in baryons. The energy levels of the excited sates are measured by a missing-mass technique for the first time, and the production rates and decay branching ratios are also measured.
+ Au collisions at 
= 200, 62.4, 39, and 19.6 GeVAidala, C.*; 長谷川 勝一; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他246名*
Physical Review C, 96(6), p.064905_1 - 064905_21, 2017/12
被引用回数：39 パーセンタイル：91.33(Physics, Nuclear)We present measurements of the elliptic flow, 
, as a function of transverse momentum (
), pseudorapidity (
), and centrality in 
Au collisions at 
200, 62.4, 39, and 19.6 GeV. The beam-energy scan of Au collisions provides a testing ground for the onset of flow signatures in small collision systems. We measure a nonzero signal at all four collision energies, which, at midrapidity and low , is consistent with predictions from viscous hydrodynamic models. Comparisons with calculations from parton transport models (based on the 
Monte Carlo generator) show good agreement with the data at midrapidity to forward (-going) rapidities and low . At backward (Au-going) rapidities and 
GeV/
, the data diverges from calculations of relative to the initial geometry, indicating the possible dominance of nongeometry related correlations, referred to as nonflow. We also present measurements of the charged-particle multiplicity (
) as a function of in central Au collisions at the same energies. We find that in Au collisions at 200 GeV the scales with over all in the PHENIX acceptance. At 62.4, and 39 GeV, scales with at midrapidity and forward rapidity, but falls off at backward rapidity. This departure from the scaling may be a further indication of nonflow effects dominating at backward rapidity.
Dupont, E.*; 大塚 直彦*; 原田 秀郎; 木村 敦; n_TOF Collaboration*; 他224名*
EPJ Web of Conferences, 146, p.07002_1 - 07002_4, 2017/09
被引用回数：5 パーセンタイル：90.74(Nuclear Science & Technology)CERNのn_TOF中性子飛行時間測定施設は、高品質の核データを熱エネルギーから数百MeVまでのエネルギー範囲で測定するために利用されている。CERNのデータ公開ポリシーに従い、核物理、宇宙核物理、原子力技術分野の広いコミュニティーに対し取得データを提供するため、n_TOF国際共同研究により取得されたデータは、標準的なフォーマットでの公開を目指している。本論文では、n_TOF国際共同研究によりこれまでに得られた様々なデータ及び関連情報を集約するとともに、国際的標準フォーマットであるEXFOR形式での整備状況について報告する。
Be(
He reaction and the cosmological lithium problem; Measurement of the cross section in a wide energy range at n_TOF at CERNBarbagallo, M.*; Musumarra, A.*; Cosentino, L.*; Maugeri, E.*; Heinitz, S.*; Mengoni, A.*; Dressler, R.*; Schumann, D.*; K
ppeler, F.*; 原田 秀郎; et al.
Physical Review Letters, 117(15), p.152701_1 - 152701_7, 2016/10
被引用回数：96 パーセンタイル：94.23(Physics, Multidisciplinary)The energy-dependent cross section of the Be(He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. Coincidences between the two alpha particles have been recorded in two Si-Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.
Lutz, M. F. M.*; 岡 眞; 他24名*
Nuclear Physics A, 948, p.93 - 105, 2016/04
被引用回数：24 パーセンタイル：56.06(Physics, Nuclear)2015年10月12日-14日にGSIで行われたEMMI短期作業部会「QCDにおける共鳴」の報告である。26人が集まってQCDの共鳴状態の物理について議論した。作業部会の目標は下記の3課題に答えることである。・QCDの共鳴状態の物理を理解するのに必要な要素は何か。・エキゾチックな量子数を持つQCDの共鳴状態はどこにあるのか・全体像をつかむために必要な実験は何か。軽いメソンとバリオンに関しては、アップ,ダウン,ストレンジクォークの状態を検討した。重いクォークを含むメソンでは、チャームを含むものに集中した。本稿では参加者の議論をまとめて、1つの描像として結論とした。
