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本稿では英語文化・国際文化の類の分野を専攻としない日本の大学生の英語を学ぶ動機について調査を行った。調査は西日本にある公立と私立の四年制大学の合計326名の学生から収集した量的データと，これらの大学の学生8 名に行ったインタビュー調査から得た質的データによって混合法を用い行った。量的データの収集には Gardner（参照 Gardner, 2004）のものから取り入れた「道具的動機」と「統合的動機」の2 種類の第二言語習得の動機を測定するために作成された14項目のアンケートを使用した。量的データの分析結果に2種類の動機付け要因の間の差異はほとんど見られなかった。質的データの収集には参加者の英語学習の経験や動機についてより詳細に聞き出す14問の自由形式の質問による半構造化インタビューを実施した。平均値が高い項目と低い項目に注目して被験者の英語学習に関する経験，学ぶ理由，姿勢について考察した。今回の調査では全般的に被験者の英語学習への意欲が高いことがうかがえた。また，被験者の多くは異文化交流に興味があり，仕事やプライベートのために実用的な英語力を身につけたいと考えていることもうかがえた。しかしながら，両方の測定（量的・質的）によって被験者達が学校で英語を教科として学ぶことについて様々な意見を持っていることがわかった。, This study investigates motivating factors of Japanese university EFL students, particularly those whose majors are not English or intercultural studies. The authors used a mixed-methods approach, combining quantitative data from 326 students at four-year universities (private and public) in Western Japan, as well as interviews with eight students from the same universities. For quantitative data collection, this study uses an adaptation of a 14-item questionnaire, created to measure two types of L2 motivation: instrumental and integrative, adapted from Gardner (Gardner, 2004). In this research, the quantitative results showed little difference between the two types of motivation. For the qualitative data analysis, semi-structured interviews were conducted, asking 14 open-ended questions to elicit more details on participants’ ESL/EFL experiences and their motivation for learning English. Looking at the items that had the highest mean scores as well as the ones with the lowest scores, this research gauges the learners’ experiences, reasons, and attitudes towards learning English. In general, participants in this survey appeared to be motivated to learn English. They seemed to be interested in cross-cultural interactions and relationships, as well as developing English competence for utilitarian matters, both professionally and privately. However, both the quantitative and qualitative measures appear to indicate that the participants had mixed opinions about studying English as a subject at school.

The 1st proton beam acceleration of the Linear IFMIF Prototype Accelerator (LIPAc) through its novel RFQ was succeeded on 13th June 2018. Addition to plenty of beam diagnostics equipped in the beam line, we prepared some radiation detectors placed around the accelerator in order to acquire supplemental information of the beam, as an indirect measurement. In the first day of the beam injection to the RFQ, the gamma-rays corresponding to certain excited states of Al of the low power beam dump were successfully detected by a LaBr3(Ce) scintillation detector. Some neutrons, which would originate from the interaction of protons with Cu somewhere, were also observed. These results proved that the beam was certain-ly accelerated up to about 2.5 MeV, and provided us a definitive confidence that the RFQ was working appro-priately from the very beginning of the commissioning. Also, the comparison of the radiation yields with the RFQ transmission provided additional information on the beam energy distribution.

In summer 2019 the IFMIF/EVEDA Radio Frequency Quadrupole (RFQ) accelerated its nominal 125 mA deuteron beam current up to 5 MeV, with 90% transmission for pulses of 1 ms at 1Hz. The Linear IFMIF Prototype Accelerator (LIPAc) is a high intensity deuteron linear accelerator; it is the demonstrator of the International Fusion Material Irradiation Facility (IFMIF). In particular the RFQ is the longest and most powerful ever operated. An intense campaign of measurements have been performed in Rokkasho to characterize several performances of this complex machine: transmission, emittances, energy spectrum and beam loading. The history and the results of the commissioning until this important project milestone are here described. An overview of the activities planned to reach CW operation is also presented., Proceedings of the 11th International Particle Accelerator Conference, IPAC2020, Caen, France

The eight-chain RF system and radio frequency quadrupole (RFQ) linac were successfully integrated at the facility of the Linear IFMIF Prototype Accelerator (LIPAc). We achieved an unprecedented high current deuteron beam up to 55 mA in pulse operation (300 μs, 1 Hz). The keys of the success were (1) understanding reflected power from RFQ to RF system, (2) tuning each RF chain individually, (3) intensive RF conditioning for holding the stable RF power in the RFQ, and (4) optimizing the beam loading compensation control. Interestingly, the reflection at the breakdown in RF conditioning was higher than an estimation and reached up to 600 kW so far. In order to avoid damage on tetrodes by the high reflection, the impedance of each circulator was accurately adjusted.

日欧国際協力のBA活動の1つとして、量研六ヶ所研究所で開発が進むIFMIF原型加速器(LIPAc)において125ミリアンペアの大電流重陽子ビームを加速する上で要となる高周波四重極線形加速器(RFQ)とその大電力高周波源の開発過程及びパルス運転で目標達成した125ミリアンペアの重陽子ビーム加速試験の成果について発表した。, 第36回プラズマ・核融合学会年会

将来のIFMIF 加速器のプロトタイプとなる原型加速器(LIPAc)の建設が、青森県六ヶ所村で欧州との共同事業として進行中である。2019年は高周波四重極加速器（RFQ）による5 MeVまでの重陽子ビーム加速試験を開始し、7月24日に世界最高記録となる125 mAの重陽子ビーム加速に成功した。本発表では、原型加速器のRFQビームコミッショニングの結果と、今後の計画について報告する。, 第36回プラズマ・核融合学会年会

The Linear IFMIF Prototype Accelerator (LIPAc) to accelerate a 9 MeV deuteron beam at 125 mA in CW is under commissioning in Rokkasho, Japan, in order to validate the low energy section of the 40 MeV IFMIF accelerator under the Broader Approach Agreement in the field of fusion energy research between Japan and EURATOM. The LIPAc RF system for RFQ consists of eight RF chains, whose maximum output power are 200 kW each in CW at 175 MHz. The RFQ is designed to accelerate a deuteron beam of 125-130 mA from 0.1 MeV to 5 MeV in CW, which demands a total RF injected power of about 1.2 MW in CW. During the RF conditioning of the RFQ up to the deuteron acceleration level starting from July 2017, we faced difficulties for increasing RF power due to the unexpected high reflected power from the RFQ to the eight RF chains and the requirement of the short pulse and high repetition rate operation for the RF conditioning. During the two experimental campaigns a drastic maintenance was carried out, and resulted in overcoming the difficulties and succeeding to perform the deuteron beam commissioning in the low duty cycle. The experience and the lesson learnt will be presented so as to provide some hints to build a similar high power accelerator facility., The 7th Accelerator Reliability Workshop (ARW 2019)

For the development of the International Fusion Materials Irradiation Facility (IFMIF) aiming at material tests for fusion power plants, the construction of the Linear IFMIF Prototype Accelerator (LIPAc) has been conducted at Rokkasho, Japan under the Broader Approach Agreement. The commissioning of LIPAc has been progressing significantly. The world most powerful RFQ successfully accelerated proton beam of 58 mA, and an important project milestone of the acceleration of deuteron beam to 5 MeV with the beam current of 125 mA in pulse mode was successfully achieved. The result proves the validity of the present RFQ design. The adjustment and tuning of the RF power system and the injector for enabling an operation at maximum performances played an important role in achieving this result. For the next step, the preparation of the high duty cycle operation of RFQ is underway. The installation of the HEBT (High Energy Beam Transport line) and the beam dump accepting 1 MW, CW beam, has been completed and a new beam transport line is under manufacturing. Also the assembly of the Superconducting RF (SRF) linac to accelerate the beam up to 9 MeV started in a clean room in Rokkasho., The 14th International Symposium on Fusion Nuclear Technology

IFMIFの実現へ向けて、工学実証及び工学設計活動（EVEDA）が日欧間のBA協定の下で実施されている。この活動の一環として、原型加速器(LIPAc)の建設が六ヶ所で進行中である。LIPAcの175MHzの高周波(RF)システムは、プラズマ加熱装置であるICRFシステムと同程度の周波数及び出力レベルを持ち、その増幅方法は同じく四極管を用いる。そのため、本ワークショップでLIPAcのRFシステムを紹介し、互いに意見を交わすのは有意義であると思われる。今回の発表では、重陽子ビーム加速レベルまで安定して出力されるように調整された、高周波四重極線形加速器(RFQ)用のRFシステムについて紹介し、その調整内容について主に発表する。また、LIPAcとしての進捗についても発表する。, Workshop on RF Heating Technology of Fusion Plasmas 2019

The integration of the 175 MHz RF system and the Radio Frequency Quadrupole (RFQ) Linac was performed at the facility of the Linear IFMIF Prototype Accelerator (LIPAc) in Rokkasho (Japan). During the integration, the RF system was adapted for dealing with an unexpected high reflection from the RFQ and a new request of a short pulse and high repetition rate operation, which was necessary for speeding up the RF conditioning of the RFQ. The reflection from the eight-port RFQ to the eight RF chains of the RF system has been studied theoretically and analyzed with measurements during the RF conditioning. The adapting of the RF system and understanding of the reflection from the RFQ boosted the progress of the RF conditioning, and the RFQ was conditioned up to a deuteron acceleration level (~560 kW in the RFQ) at 300 μs/1 Hz, which allowed us to start a deuteron beam commissioning at the low duty cycle. It was also confirmed that the amplitude control of the RF system was properly adjusted to a beam loading of 45 mA deuteron beam., 28th IEEE Symposium on Fusion Engineering (SOFE2019)

日欧の国際協力として実施してきたIFMIF/EVEDAで培った知見や研究資産を最大限に有効活用し、量子科学技術研究開発機構六ヶ所核融合研究所において40MeV-125mAの重陽子ビームと液体リチウムターゲットによる先進核融合中性子源（A-FNS）を建設する国内計画が検討されている。A-FNSの第一の目標は核融合炉材料等の中性子照射試験を行うことであるが、医療・産業応用等を含めた多用途利用を考慮した強力中性子源としても検討をしている。講演では現在進められつつあるA-FNSの計画について報告する。, 第6回加速器施設安全シンポジウム

The LIPAc accelerator is 9-MeV, 125-mA CW deuteron accelerator that aims to validate the technology that will be used in the future IFMIF accelerator (40-MeV, 2 x 125-mA CW). LIPAc is presently under beam commissioning of the second acceleration stage (injector and Radio Frequency Quadrupole) at 5 MeV. In this stage two types of BPM¿s are used: four stripline-type to control the transverse position and phase at the Medium Energy Beam Transport line (MEBT), and three other stripline-type mainly for the precise measurements of the mean beam energy at the Diagnostics Plate. All the BPM¿s have been successfully tested and served to increase the duty cycle and the average power of the beam delivered down to the beam dump. Moreover, the BPM¿s were key devices for the transverse beam positioning and longitudinal beam tuning and validation of the RFQ and re-buncher cavities at the MEBT. In this contribution, an overview of the beam position monitors system installation and characterization in the facility will be reported. First tests of the system with the upgraded acquisition electronics for the next phase will be also presented., Proceedings of the 8th International Beam Instrumentation Conference, IBIC2019, Malmö, Sweden

The IFMIF/EVEDA RFQ is the longest and powerful operated. Therefore, it requires a careful characterization from several aspects: beam dynamics, RF, mechanics, installation and commissioning. Due to the very large power handling, the preliminary beam operation was decided to be performed with a low proton beam current at one half of the voltage needed for deuteron accelera-tion, i.e. from 8 mA to 30 mA at 2.5 MeV in pulsed mode, with respect to the nominal 130-mA deuteron beam at 5 MeV in CW. In this framework, it will be presented the characterization of the RFQ in terms of simulation and measurements., 29th Linear Accelerator Conference-LINAC18

International Fusion Materials Irradiation Facility (IFMIF) is the neutron source for simulating fusion reactor environment using two 40 MeV/125 mA CW D+ beams. LIPAc facility is under construction in Rokkasho for validating 9 MeV/125 mA CW linac technology as a prototype of the IFMIF accelerator. Commissioning of 5 MeV CW RFQ is underway after the completion of installation of RFQ, MEBT, diagnostic plate. low power beam dump, RF power system and their auxiliaries. As the first step, high power RF conditioning is planned to complete in early 2018 and beam commissioning will start with stepwise approach at the same time. The status of LIPAc construction for preparing 9 MeV acceleration and results of RFQ beam commissioning are presented., 29th Linear Accelerator Conference-LINAC18

日本と欧州による核融合エネルギー分野における国際共同プロジェクトの一つとして始まった 強力中性子源である国際核融合材料照射施設の工学実証・工学設計活動(IFMIF/EVEDA) のうち、原型加速器（LIPAc、Linear IFMIF Prototype Accelerator）の製作及び据付調整が本格化し大きく進展した。2018年度からはビーム試験が開始された。IFMIF原型加速器の現状について施設現状報告をポスターにて行う。, 第15回日本加速器学会年会

International audience; The IFMIF project aiming at material tests for a future fusion DEMO reactor is under the EVEDA phase in the BA Agreement of fusion program between Japan and EU. As the accelerator activity, the installation and commissioning of the Linear IFMIF Prototype Accelerator (LIPAc) is at the second stage of demonstration of the feasibility of the low energy section of an IFMIF deuteron accelerator up to 9 MeV with a beam current of 125 mA, CW. The installation of injector, RFQ, MEBT, D-Plate and LPBD for LIPAc with 8 coaxial high-power transmission lines and RF power system was just done in 2017 at Rokkasho, Japan. After that, the RF conditioning of RFQ for beam commissioning is underway. The beam commissioning of RFQ with H⁺/D⁺ and the acceleration demonstration up to 5 MeV-125 mA-0.1% duty cycle with D⁺ will be done.

IFMIF, the International Fusion Materials Irradiation Facility, is an accelerator-based neutron source that will use Li(d, xn) reactions to generate a flux of neutrons with a broad peak at 14 MeV equivalent to the conditions of the Deuterium-Tritium reactions in a fusion power plant. IFMIF is conceived for fusion materials testing. The IFMIF prototype linear accelerator (LIPAc) is jointly developed by Europe and Japan within the IFMIF EVEDA project: it is composed of an ion source, a LEBT, an RFQ, a MEBT and a SC linac, with a final energy of 9 MeV. The 4-vane Radio Frequency Quadrupole (RFQ), developed by INFN in Italy, will accelerate a 130 mA deuteron beam from 0.1 to 5 MeV in continuous wave, for a beam power of 650 kW. The 9.8 m long 175 MHz cavity is composed of 18 x 0.54 m long modules flanged together and aligned within 0.3 mm tolerance. The RFQ was completed, delivered and assembled at the Rokkasho site and is presently under extended RF tests. The second phase of beam commissioning (up to 2.5 MeV/u) was scheduled to start at the end of 2017. Several unexpected issues and incidents significantly delayed the original program, which is however proceeding step by step toward the full achievement of its goals., 9th International Particle Accelerator COnference - IPAC2018

LIPAc* will be a 9 MeV, 125 mA CW deuteron accelerator which aims to validate the technology to be used as neutron source of the IFMIF facility. Those facilities are essential for future fusion reactors material research. A 175 MHz RFQ will increase the energy up to 5 MeV before a Superconducting RF (SRF) linac with eight 175 MHz Half Wave Resonators brings the particles up to the final energy of 9 MeV. Between both stages, a Medium Energy Beam Transport line (MEBT)** aims at transporting and matching the beam between the RFQ and the SRF linac. The transverse focusing of the beam is controlled by five quadrupole magnets with integrated steerers, grouped in one triplet and one doublet. Two buncher cavities handle the longitudinal dynamics. Two movable scraper systems are included to purify the beam optics coming out the RFQ and avoid losses in the SRF linac. In this contribution, checkout of the beamline and its ancillaries in Japan is reported. Tests carried out on the beamline prior to the MEBT beam commissioning are described, focusing in vacuum tests, magnets powering, buncher conditioning and scrapers movement., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

The IFMIF-EVEDA RFQ is composed of 18 modules for a total length of 9.8 m and is designed to accelerate the 125 mA D⁺ beam up to 5 MeV at the frequency of 175 MHz. The RFQ is subdivided into three Super-Modules of six modules each. The Super-Modules were shipped to Rokkasho (Japan) at the beginning of 2016, pre-assembled 3 m far from the final location and tuned to reach target field flatness requirements. Just after conclusion of injector commissioning, the tuned RFQ was disassembled, moved and reassembled in the final location. After confirmation that field flatness was not affected by this movement, high power couplers were installed and tuned and all the structure was baked. Assembling, tuning and coupling results will be presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

All IFMIF - EVEDA RFQ modules were completed in summer 2015. In the previous year the last three modules were RF tested at LNL at nominal power up to cw operation. At the beginning of this year all the modules were assembled in three 3.3 m long super-modules structures that were shipped to Japan. RFQ was then installed and tuned with provisional aluminum tuners and end plates to nominal frequency and field distribution. Replacement of movable aluminum components with copper fixed ones increased cavity quality value not affecting field flatness and frequency., Proceedings of the 25th Russian Particle Accelerator Conf., RuPAC2016, St. Petersburg, Russia

The LIPAc accelerator aims to operate in Rokkasho Fusion Institute a 125 mA/CW deuteron beam at 9 MeV to validate the concept of IFMIF's accelerators that will operate in CW 125 mA at 40 MeV. The 2.45 GHz ECR injector developed by CEA-Saclay is designed to deliver 140 mA/100 keV CW D⁺ beam with 99% D⁺ fraction ratio. Its LEBT relies on a dual solenoid focusing system to transport and match the beam into the RFQ. The normalized RMS emittance at the RFQ injection cone is required to be within 0.25π mm·mrad to allow 96% transmission through the 9.81 m long RFQ. An equal perveance H⁺ beam of half current and half energy as nominal with D⁺ is used to avoid activation during commissioning. The injector commissioning at Rokkasho is divided into three phases to characterize the emittance between the two solenoids of the LEBT (A1) and just downstream the RFQ injection cone (A2) and the extraction system of the source (A3). Phase A1 has been achieved and phase A2 continues in 2016 in order to reach the required beam parameters and to match the beam into the RFQ. This paper reports the commissioning results of phase A1 and the intermediate ones of phase A2 for H⁺ and D⁺ beams., Proceedings of the 22nd Int. Workshop on ECR Ion Sources, ECRIS2016, Busan, Korea