Umemori, Kensei*; Furuya, Takaaki*; Kako, Eiji*; Noguchi, Shuichi*; Sakai, Hiroshi*; Sato, Masato*; Shishido, Toshio*; Watanabe, Ken*; Yamamoto, Yasuchika*; Shinoe, Kenji*; et al.
Proceedings of 15th International Conference on RF Superconductivity (SRF 2011) (Internet), p.956 - 961, 2011/07
The Compact ERL (cERL) project is advanced in Japan. Its aim is to demonstrate the circulation of 100 mA electron beams with energy of 35-200 MeV. Superconducting cavities are key components for realizing ERL and used for injector part and main linac part. Critical issue for the injector part is the development of input power coupler. Prototype input couplers were fabricated and high power test was performed. Cooling ability of HOM coupler is also important for CW operation of cavity. At main linac part, HOM damped 9-cell cavities are applied to avoid BBU instabilities. Prototypes were fabricated for the cavity, the input coupler and the HOM absorber. Their performance was investigated. For both parts, cryomodules are under construction and will be completed in 2012.
Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05
Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.
Sakai, Hiroshi*; Furuya, Takaaki*; Kako, Eiji*; Noguchi, Shuichi*; Sato, Masato*; Sakanaka, Shogo*; Shishido, Toshio*; Takahashi, Takeshi*; Umemori, Kensei*; Watanabe, Ken*; et al.
Proceedings of 45th Advanced ICFA Beam Dynamics Workshop on Energy Recovery Linacs (ERL '09) (Internet), p.57 - 62, 2010/05
Development of a SC Cavity Injector Cryomodule and Main linac Cryomodule for the compact ERL is being continued at KEK since 2006. Design of an injector cryomodule containing three 2-cell 1.3-GHz cavities for Injector Cryomodule and two 9-cell 1.3-GHz cavities for Main linac Cryomodule are almost completed. Status of R&D and design details are reported.
Umemori, Kensei*; Furuya, Takaaki*; Kako, Eiji*; Noguchi, Shuichi*; Sakai, Hiroshi*; Sato, Masato*; Shishido, Toshio*; Takahashi, Takeshi*; Watanabe, Ken*; Yamamoto, Yasuchika*; et al.
Proceedings of 14th International Conference on RF Superconductivity (SRF 2009) (Internet), p.896 - 901, 2009/09
Construction of the Compact ERL is planned in Japan, in order to test the key technology to realize a future ERL based X-ray light source. The operation of 60-200 MeV beam energy and 100 mA beam current are proposed. The superconducting cavity is one of the key components and applied for the injector part and the main linac part. At the injector part, most challenging issue is an input coupler, which has to handle more than 300 kW input power per cavity. On the other hand, strong HOM damping is required for the main linac, in order to avoid beam instabilities and large heat load at cryomodules. Status of cavity developments, together with cryomodule developments, including input couplers and HOM couplers/absorbers, are described in this paper.
Sakanaka, Shogo*; Ago, Tomonori*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; Harada, Kentaro*; Hiramatsu, Shigenori*; Honda, Toru*; et al.
Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM), p.205 - 207, 2008/06
Future synchrotron light sources based on the energy-recovery linacs (ERLs) are expected to be capable of producing super-brilliant and/or ultra-short pulses of synchrotron radiation. Our Japanese collaboration team is making efforts for realizing an ERL-based hard X-ray source. We report recent progress in our R&D efforts.
Yamamoto, Yasuchika*; Hayano, Hitoshi*; Kako, Eiji*; Noguchi, Shuichi*; Sato, Masato*; Shishido, Toshio*; Umemori, Kensei*; Watanabe, Ken*; Sakai, Hiroshi*; Shinoe, Kenji*; et al.
Proceedings of 5th Annual Meeting of Particle Accelerator Society of Japan and 33rd Linear Accelerator Meeting in Japan (CD-ROM), p.888 - 891, 2008/00
In KEK, the new Superconducting RF Test Facility(STF) is being constructed, including the electro-polish system (EP), the high pressure rinsing system (HPR), the clean-room, the refrigerator system, the high power RF source system, and the vertical test system. The cavity is generally measured in the vertical cryostat for the performance test. The new vertical test facility was constructed since the last year, and completed at the beginning of March. The first test was done for the total system check at the beginning of July.
Hoshiba, Hideaki; Hashimoto, Makoto; Irokawa, H.; Usui, Toshihide; Sato, Hayato; Emori, Shuichi
JNC TN9410 2004-017, 170 Pages, 2004/08
While the JOYO MK-III Project, after the modification of primary coolant system started in oct.2000 and the integrated function tests, from Jun.2003, the performance test was executed for the purpose of verification of designed performance and confirmation of basic characteristics as an irradiation reactor. While the JOYO MK-III performance test, 28 tests were executed. Radiation control section took charge of 3 of them, "Dose Rate Distribution", "Radiation Control" and "Gaseous Waste Radioactive Concentration Measurement". The performance tests in charge of radiation control section was started on Jun.27, 2003, that is before the start-up of reactor, and were carried out when the thermal output of reactor was 40MWt, 70MWt, 105MWt and effective full power, 140MWt. The pre-operation tests in charge of radiation control section are "Test of dose rate measurement in operation and after shutdown". "Test of radioactive concentration measurement of air", and "Test of gaseous waste processing performance". The final test was "Test of dose rate measurement after shutdown", which was executed on Nov.27 2003. JOYO passed the inspection and the performance test was finished. The representative results in these performance tests are; 1.Every result is under the criterion 2.Dose rate and monitoring data are totally less than the data in MK-II operation. Though it confirmed that all the data are under the criterion, it is considered that these tests should be performed at proper intervals because the circumstances may change.
Kano, Yutaka; Hoshiba, Hideaki; Emori, Shuichi; T.Higuchi
JNC TN9410 2004-012, 51 Pages, 2004/03
The 13th annual inspection at the experimental fast reactor JOYO had been executed from June 1, 2000 to November 27,2003.While this inspection,in addition to the regular maintenance and repair, some countermeasure works based on safety overhaul and works relevant to the heat transport system modification for upgrading the irradiation performance (MK-III modfication) in the under floor of reactor building were implemented. Duration of the inspection was about 3.5 years, longer than past inspections. While the inspection, the replacement of the internal heat exchanger (IHX) A,B, in primary coolant system, and relevant pipes was considered important in radiation control. The point of radiation control of this work was external exposure to workers.The expectation of exposure dose in the annual inspection and the MK-III modification were made for every work subject in consideration of procedure, number of workers, period and place of the work. The expectation of total exposure in the annual inspection, summed up the yearly expectation from 2000 to 2003 , was 1156 man-mSv. While In the MK-III modification from June 1, 2000 to November 30, 2002 , the expectation of total exposure was 7135 man-mSv. Furthermore, all the while in the MK-III modification, We call for work end department that workers exposure was as low as practical. As a result, total exposure was 633 man-mSv in the annual inspection, and 2386 man-mSv in the MK-III modification. Both of total result exposure was about 30-50 % of the expectation, and every worker's exposure were controlled under the criteria of exposure control. Finally, the works in the 13th annuall inspection was properly executed.
Hashimoto, Tomoharu; Hashimoto, Makoto; Ishikawa, Masayasu; Emori, Shuichi
Hoken Butsuri, 39(3), 229- Pages, 2004/00
It was executed that the investigation on the performance of dosimeters for individual monitoring which compare present TLD with recently dosimeters, OSL, Glass dosimeter, EPD, SSTD. It also surveyed operating method of each dosimeter.
Hashimoto, Tomoharu; Ishikawa, Masayasu; Emori, Shuichi
JNC TN9420 2003-001, 50 Pages, 2003/09
We investigate the new tipe dosimeter to prepare for renewal of the present TLD in the near future.As a result of investigation, if we pursue the rationalization and convenience in the operation of dosimeter more and more, then we will recommend the electric pocket dosimeter positively.
Emoto, Takehiko; Torii, Tatsuo; Nozaki, Tatsuo; Saito, Kei; Emori, Shuichi; Ando, Hideki
PNC TN9410 96-299, 74 Pages, 1996/08
The technique has been developed to measure the dose-rate distribution of radiation easily. The detector is made of plastic scintillation fibers (of following PSFs). The technique is based on the time of flight method, that is to measure the time difference of scintillation reaching from a incidence position to both ends of fibers. Measuring devices were built as trials. The position resolution was measured with collimated ray. The dose-rate linearity and the energy response were measured with an irradiation equipment of ray. Then, the devices were applied to the dose-rate distribution measurements in facilities. The tests were carried out to turn the technique into practicable use. Main results are as follows; (1) The continuos dose-rate distribution of ray can be measured with a single detector. The result of a measurement is illustrated on the screen of a device immediately. (2) The upper limit of counting rate measuring range is 10 cps. The upper limit of ray dose-rate measuring range is 1 mSv/h (calculated value) for a detector of "0.25 mm 1 peace, 10 m length". (3) The detection efficiency does not depend on the ray energy between 500 keV and 1.5 MeV. (4) The practical length of PSFs is up to about 10 m for the dose-rate distribution measurement. (5) When the dose-rate distribution has sharp peaks, the output distribution of measurement is slightly flattened against the actual distribution based on the detector characteristic of position resolution. The unfolding method can correct this effect. (6) It is possible to discriminate the energy and type of radiation, if the pulse height output of a photomultiplire is corrected in each incidence position with the multi-parameter measuring method.
Takashima, Hideki; Iwasa, Atsutoshi; Eguchi, Kazutoshi; Yoshimochi, Hiroshi; Obayashi, Hiroshi; Emori, Shuichi
no journal, ,
In Alpha- Facility (AGF),Japan Atomic Energy Agency Oarai, the situation of the existing nuclide composition ratio etc. has changed greatly by manufacturing of the Am content mixed oxide fuel and executing the characteristic test. Therefore, the nuclide composition ratio etc. concerned were measuring analyzed, and the radiation management method in the emergency was examined as a result. As for the analysis sample, it gathered in the cell and the glove box (17 places) in facility, and the nuclide composition ratio was evaluated from the measurement result of the mass spectrometry etc. As a result, the nuclide composition approximated to the MA fuel pellet was seen of many sample and the difference was seen in the nuclide composition of each sample (especially, Am-241, Pu-239, and Pu-240). The result of the radiation management method in the emergency becomes as follows from these. (1) It is possible to execute immediately the initial assessment of internal expose from these data obtained this time and all alpha radioactivity that can be measured comparatively promptly by the presumption evaluation of radioactivities of each nuclides such as Pu and Am on the accident generation place. (2) If happened an abnormal discharge and the air contamination etc. of A radioactive substance, the originating place and the nuclide composition can be presumed by evaluating the radioactivity of Am-241 and all alpha radioactivity that can be measured comparatively promptly.
Sawamura, Masaru; Umemori, Kensei*; Sakanaka, Shogo*; Suwada, Tsuyoshi*; Takahashi, Takeshi*; Furuya, Takaaki*; Noguchi, Shuichi*; Kako, Eiji*; Shishido, Toshio*; Watanabe, Ken*; et al.
no journal, ,
Superconducting accelerator cavities are essential for the energy-recovery linac. The superconducting cavities are used in an injector and a main linac. A new model has been designed for the ERL. A center-single-cell cavity, an end-single-cell cavity and 9-cell cavity have been constructed. Vertical tests were performed for the center-single-cell cavity and the end-single cell cavity. A 2-cell cavity for the injector is under construction.
Saito, Kei; Takashima, Hideki; Emori, Shuichi; Soma, Susumu; Takada, Chie
no journal, ,
no abstracts in English
Usui, Toshihide; Takashima, Hideki; Saito, Kei; Tagawa, Hiroshi; Ito, Kimio; Emori, Shuichi
no journal, ,
no abstracts in English