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Zr + 
at 27 MeV/nucleonHwang, J.*; Chillery, T.*; 堂園 昌伯*; 今井 伸明*; 道正 新一郎*; 炭竃 聡之*; 千賀 信幸*; 大田 晋輔*; 中山 梓介; 他49名*
Progress of Theoretical and Experimental Physics (Internet), 2024(9), p.093D03_1 - 093D03_12, 2024/09
被引用回数：0核変換は高レベル廃棄物の再処理、特に使用済み燃料からZrのような長寿命核種を処理するための有望な手段であると考えられている。これらの核種に対する核反応データを蓄積することは、核変換の検討や反応機構を包括的に理解するために不可欠である。本研究では、Zrに対する陽子入射反応からの残留核生成断面積を、核子当たり27MeVのエネルギーで逆運動学法を用いて測定した。理研RIBFのOEDOビームラインを用いて、
Nb, 
Zr, 
Yの各同位体の生成断面積を導出した。励起関数について、TALYSやCCONEによる理論予測は、本研究や先行研究の実験値と概ね良い一致を示した。本研究で測定された断面積は、廃棄物処理に関する将来の検討のための貴重なデータとなる。
Zr + d reaction cross sections measured at 28 MeV/nucleonChillery, T.*; Hwang, J.*; 堂園 昌伯*; 今井 伸明*; 道正 新一郎*; 炭竃 聡之*; 千賀 信幸*; 大田 晋輔*; 中山 梓介; 他49名*
Progress of Theoretical and Experimental Physics (Internet), 2023(12), p.121D01_1 - 121D01_11, 2023/12
被引用回数：2 パーセンタイル：34.43(Physics, Multidisciplinary)重陽子は弱束縛系でありクーロン力と核力の下で容易に陽子と中性子に分解する。これまでの実験からは、核子当たり50から200MeVといった高入射エネルギーではこの分解過程が残留核生成に大きな影響を与えることが示されている。しかし、核子当たり50MeV以下のエネルギーでの断面積データはまだ不足している。本研究では、BigRIPSセパレータ、OEDOビームライン、SHARAQスぺクトロメータを用いて、Zr+d反応断面積を核子当たり約28MeVにおいて逆運動学法を用いて測定した。本研究で得られた断面積を過去の測定結果や理論計算と比較した。重陽子の分解の効果を定量的に考慮したDEURACS計算により実験データがよく再現された。本研究で測定された低エネルギー領域におけるデータは、将来の核廃棄物処理施設の検討に役立つと考えられる。
五十嵐 進*; 野村 昌弘; 田村 文彦; 山本 昌亘; 島田 太平; 他49名*
Progress of Theoretical and Experimental Physics (Internet), 2021(3), p.033G01_1 - 033G01_28, 2021/03
被引用回数：6 パーセンタイル：42.98(Physics, Multidisciplinary)The J-PARC Main Ring (MR) has supplied the high-intensity proton beam for the T2K long- baseline neutrino experiment since 2010. The present beam power is 510 kW and the total number of protons on the target reaches 3.64
10
. To observe charge-conjugation and parity- transformation (CP) violation in the lepton sector with high accuracy, more protons need to be delivered to the T2K target. The project to upgrade the beam power to 1.3 MW started as a mid-term plan of the MR. In parallel to preparing a full technical design report, the technical designs of hardware upgrades using new technologies and all accelerator components that are necessary to deliver the 1.3 MW beam power are summarized and consolidated in this short paper. Further, this paper includes beam dynamics studies and simulation results for handling 3.310
protons per pulse without significant beam loss in the ring and transport lines.
pairs from open heavy flavor in 
and 
collisions at 
= 200 GeVAdare, A.*; 長谷川 勝一; 今井 憲一; 永宮 正治; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他497名*
Physical Review C, 96(2), p.024907_1 - 024907_19, 2017/08
被引用回数：11 パーセンタイル：63.77(Physics, Nuclear)We report a measurement of pairs from semileptonic heavy-flavor decays in collisions at = 200 GeV. The pair yield from 
and 
is separated by exploiting a double differential fit done simultaneously in dielectron invariant mass and 
. We used three different event generators, 
, 
, and 
, to simulate the spectra from and production. The data can be well described by all three generators within the detector acceptance. However, when using the generators to extrapolate to 
, significant differences are observed for the total cross section. These difference are less pronounced for than for . The same model dependence was observed in already published data. The data are also directly compared with data in mass and , and within the statistical accuracy no nuclear modification is seen.
橋本 直*; 谷田 聖; 他49名*
IEEE Transactions on Applied Superconductivity, 27(4), p.2100905_1 - 2100905_5, 2017/06
被引用回数：12 パーセンタイル：52.76(Engineering, Electrical & Electronic)We are developing a new technique to apply transition-edge sensors (TESs) to X-ray spectroscopy of exotic atoms, especially of kaonic atoms. To demonstrate the feasibility of this pioneering project, performance of a TES-based X-ray detector was evaluated in pion- and kaon-beam environments at particle accelerators. We successfully observed X-rays from pionic-carbon atoms with a resolution as good as 7 eV FWHM at 6 keV. Also at a kaon beamline, we confirmed that the TES spectrometer will be able to achieve our resolution goal, 6 eV, in our first scientific campaign to measure X-rays from kaonic-helium atoms.
= 200 GeVAdare, A.*; 長谷川 勝一; 今井 憲一; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他493名*
Physical Review C, 92(3), p.034914_1 - 034914_21, 2015/09
被引用回数：25 パーセンタイル：82.26(Physics, Nuclear)We present a systematic study of charged-pion and kaon interferometry in Au + Au collisions at = 200 GeV. The kaon mean source radii are found to be larger than pion radii in the outward and longitudinal directions for the same transverse mass; this difference increases for more central collisions. The azimuthal angle dependence of the radii was measured with respect to the second-order event plane and similar oscillations of the source radii were found for pions and kaons. Hydrodynamic models qualitatively describe the similar oscillations of the mean source radii for pions and kaons, but they do not fully describe the transverse-mass dependence of the oscillations.
橋本 直*; 谷田 聖; 他49名*
no journal, ,
We are developing a new technique to study the strong interaction between a hadron and an atomic nucleus: high-resolution TES-based X-ray spectroscopy of hadronic atoms. The strong interaction induces a shift and broadening of the atomic energy levels from their purely electromagnetic values. Thus, precise measurements of the X-ray-emission lines of a hadronic atom can reveal the hadron-nucleus strong interaction at zero kinetic energy. Presently, we are preparing to measure the 
-
X-ray lines of kaonic helium-3 and helium-4 (6.2 keV and 6.4 keV, respectively) at the Japan Proton Accelerator Research Complex (J-PARC; Tokai, Japan). If we determined the strong-force shift in the helium 2p orbital to a precision of 0.2 eV, we could distinguish between the two leading antikaon-nucleus strong-interaction models. Here, we plan to use a 240-pixel TES array of about 23 mm
collecting area with 4 
m thick Bi absorbers. Our project represents the first attempt to use a TES-based X-ray spectrometer in a charged-particle beamline, and we have identified some challenges: (1) energy resolution is deteriorated by charged-particle passages; (2) a continuum background in the X-ray spectrum is generated by charged particles; (3) the science X-ray yield is expected to be very low, at 200 counts per week for the kaonic-helium-atom experiment. Here we present the status of our project.
