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Nakajima, Kenji; Kikuchi, Tatsuya*; Kawamura, Seiko; Kambara, Wataru*
EPJ Web of Conferences, 272, p.02012_1 - 02012_8, 2022/11
We will present some of attempts on AMATEAS, a cold-neutron chopper spectrometer at a pulsed source, to increase time-windows at a single-measurement condition. One of ways is that, by allowing interveined trajectories on the time-of-flight diagram, the usable width selectable for 
is can be increased. Based on our experiences, the conditions of pulse repetition rate multiplication based polychromatic 
measurements on chopper spectrometers at pulsed sources will be discussed. Optimization of wide-band polychromatic measurements and a generalized formulated condition will be proposed. Application of our idea to existing spectrometers and to the criteria design of an optimized chopper spectrometer will be also discussed with suggesting further possibility to improve efficiency by modifying the pulse shaping chopper.
Yamazaki, Dai; Ebisawa, Toru*
Hamon, 15(1), p.51 - 54, 2005/01
Neutron spin handling could be used for beam control and spectroscopy. Energy analysis could be performed with Drabkin energy filters, by which inelastic component with a 
, a 
or a 
could be extracted for all incident wavelength. Pulsed spin-flipper and polarization analyzer could be used as a neutron chopper (spin-flip chopper) whose opening time, number of windows and phase are controlled independently. It was demonstrated that S/N ratio can be enhanced up to 1.5 
10
by installing three spin-flip choppers in sequence.
Oyama, Kenji*; Ito, Shinichi*; Otomo, Toshiya*; Osakabe, Toyotaka; Suzuki, Junichi; Matsuda, Masaaki; Kuwahara, Keitaro*; Arai, Masatoshi*
Applied Physics A, 74(Suppl.1), p.S1598 - S1600, 2002/12
Times Cited Count：2 Percentile：11.51(Materials Science, Multidisciplinary)no abstracts in English
Yokota, Wataru; Fukuda, Mitsuhiro; Okumura, Susumu; Arakawa, Kazuo; Ishibori, Ikuo; Nara, Takayuki; Agematsu, Takashi; Tamura, Hiroyuki; Kurashima, Satoshi; Nakamura, Yoshiteru; et al.
JAERI-Review 2000-024, TIARA Annual Report 1999, p.273 - 275, 2000/10
no abstracts in English
Yokota, Wataru; Fukuda, Mitsuhiro; Okumura, Susumu; Arakawa, Kazuo; Nakamura, Yoshiteru; Nara, Takayuki; Agematsu, Takashi; Ishibori, Ikuo
Review of Scientific Instruments, 68(4), p.1714 - 1719, 1997/04
Times Cited Count：12 Percentile：66.13(Instruments & Instrumentation)no abstracts in English
*; Okada, Sohei; Kawasuso, Atsuo
JAERI-Conf 97-003, p.472 - 475, 1997/00
no abstracts in English
Arakawa, Kazuo; Nakamura, Yoshiteru; Yokota, Wataru; Nara, Takayuki; Agematsu, Takashi; Okumura, Susumu; Ishibori, Ikuo; Fukuda, Mitsuhiro
Proceedings of 14th International Conference on Cyclotrons and Their Applications, 0, p.57 - 60, 1996/00
no abstracts in English
Arakawa, Kazuo; Nakamura, Yoshiteru; Yokota, Wataru; Nara, Takayuki; Agematsu, Takashi; Okumura, Susumu; Ishibori, Ikuo; Fukuda, Mitsuhiro
JAERI-Conf 95-021, 0, p.32 - 34, 1995/10
no abstracts in English
Yokota, Wataru; Arakawa, Kazuo; Nakamura, Yoshiteru; Fukuda, Mitsuhiro; Kamiya, Tomihiro; Tanaka, Ryuichi; Tachikawa, T.*; Mita, T.*; Sato, T.*
Proceedings of 12th International Conference on Cyclotrons and Their Applications (CYCLOTRONS 89), p.388 - 391, 1991/07
no abstracts in English
Nakajima, Kenji; Kawamura, Seiko; Kikuchi, Tatsuya; Kawakita, Yukinobu; Inamura, Yasuhiro; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Soyama, Kazuhiko; Harada, Masahide; Oikawa, Kenichi; et al.
no journal, ,
Nakajima, Kenji; Kawamura, Seiko; Kikuchi, Tatsuya; Inamura, Yasuhiro; Kawakita, Yukinobu; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Soyama, Kazuhiko; Arai, Masatoshi; Aoyama, Kazuhiro; et al.
no journal, ,
no abstracts in English
Nakajima, Kenji; Kawamura, Seiko; Kikuchi, Tatsuya; Inamura, Yasuhiro; Kawakita, Yukinobu; Nakamura, Mitsutaka; Kajimoto, Ryoichi; Takata, Shinichi; Oikawa, Kenichi; Harada, Masahide
no journal, ,
AMATERAS is a cold-neutron multi disk-chopper spectrometer at Materials and Life Science Experimental Facility (MLF) in J-PARC. By using a pulse shaping chopper and owing to the high peak intensity from a coupled moderator source at MLF, AMATERAS is designed to realize high intensity and fine and flexible energy resolution measurements in quasielastic and inelastic neutron scattering experiments from cold to thermal neutron energy region. The spectrometer has had the first neutron beam in May 2009 and had the first user in December 2009. The user program on AMATERAS is running successfully for 5 years. Until June, 2014, experiments of 61 general proposals have been carried out, which have resulted more than 20 papers, 5 theses and nearly a hundred of presentations at scientific meetings. In parallel to the user program, machine study and commissioning work to improve spectrometer performance have been continuously done. Recently, we have finished refurbishment of the beam transport section. Also, there is a progress in background reduction work, development of data analysis method and preparation in sample environments. In this presentation, we will present the current status of AMATERAS together with ideas of future upgrade plans.
Nakajima, Kenji; Kawamura, Seiko; Kikuchi, Tatsuya; Kawakita, Yukinobu; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Aoyama, Kazuhiro; Kambara, Wataru*; Yamauchi, Yasuhiro; Kubo, Naoya
no journal, ,
AMATERAS is a cold-neutron multi disk-chopper spectrometer at Materials and Life Science Experimental Facility (MLF) in J-PARC. The spectrometer has had the first neutron beam in May 2009 and had the first user in December 2009. The user program on AMATERAS is running successfully for 5 years. In this presentation, we will present the current status of AMATERAS together with ideas of future upgrade plans.
Nakajima, Kenji; Kawamura, Seiko; Kikuchi, Tatsuya; Kawakita, Yukinobu; Inamura, Yasuhiro; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Aoyama, Kazuhiro; Kambara, Wataru*; Wakai, Daisuke*
no journal, ,
AMATERAS is a cold-neutron disk-chopper spectrometer at Materials and Life Science Experimental Facility (MLF) in J-PARC. As one of the first-generation disk-chopper spectrometers with a pulse shaping chopper, the spectrometer started its operation in 2009. Until May 2016, experiments of more than 80 proposals have been carried out, which have produced 36 papers, 7 theses and nearly a hundred of presentations at scientific meetings. In past 8 years, we have been accumulating experiences of operation of a pulse-shaping-type chopper spectrometer and are facing several problems with a beam-transport, back-ground, chopper operations etc. In this presentation, we will present our experiences and issues with operation of AMATERAS, which might be of help of other similar spectrometers in operation or in the planning stage.
Kawamura, Seiko
no journal, ,
Cold-neutron disk chopper spectrometer, AMATERAS, is a neutron scattering instrument constructed at BL14 in the Materials and Life Science Experimental Facility (MLF) in J-PARC for quasielastic and inelastic neutron scattering experiments. The instrument is dedicated to the low energy ranging approximately from 1 to 80 meV, and realizes high beam intensity and flexible energy resolution owing to the coupled moderator and three sets of the fast disk chopper. By using this instrument, many users' experiments in various research fields such as quantum spin systems, strongly correlated electron systems, liquids and polymers have been performed in the last decade. In the presentation, each component of the instrument, available sample environment and recent results are introduced.
measurements on chopper spectrometersNakajima, Kenji; Kikuchi, Tatsuya*; Kawamura, Seiko
no journal, ,
In this study, the conditions of pulse repetition rate multiplication based polychromatic measurements on chopper spectrometers at pulsed sources are described. By allowing interveined trajectories on the time-of-flight diagram, the usable width selectable for s can be increased. Optimization of wide-band polychromatic measurements is investigated, and a generalized condition is formulated. Application of our idea to existing spectrometers and to the criteria design of an optimized chopper spectrometer is also discussed.
Kawamura, Seiko; Kofu, Maiko; Murai, Naoki; Inamura, Yasuhiro; Nirei, Masami; Piyawongwatthana, P.; Wakai, Daisuke*; Nakajima, Kenji
no journal, ,
