Faculty Profiles - SHIMIZU Hirohiko

Papers - SHIMIZU Hirohiko

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Parametric resonance enhancement in neutron interferometry and application for the search for non-Newtonian gravity Reviewed Open Access

Vladimir Gudkov, Hirohiko M. Shimizu, Geoffrey L. Greene

PHYSICAL REVIEW C Vol. 83 ( 2 ) 2011.2

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER PHYSICAL SOC

The parametric resonance enhancement of the phase of neutrons due to non-Newtonian anomalous gravitation is considered. The existence of such resonances is confirmed by numerical calculations. A possible experimental scheme for observing this effect is discussed based on an existing neutron interferometer design.

DOI： 10.1103/PhysRevC.83.025501

A Transport Optics for Pulsed Ultracold Neutrons Reviewed

H.M.Shimizu, Y.Iwashita, M.Kitaguchi, K.Mishima and T.Yoshioka

Nucl. Instrum. Methods A Vol. 634 page： 25-27 2011

Multilayer Neutron Interferometer with Complete Path Separation Reviewed Open Access

Yoshichika Seki, Haruhiko Funahashi, Masaaki Kitaguchi, Masahiro Hino, Yoshie Otake, Kaoru Taketani, Hirohiko M. Shimizu

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN Vol. 79 ( 12 ) 2010.12

Language：English Publishing type：Research paper (scientific journal) Publisher：PHYSICAL SOC JAPAN

We have developed a new multi layer cold-neutron interferometer using a pair of beam splitting etalons (BSEs) with an air gap of 189 mu m in spacing. This is the first multilayer neutron interferometer that separates two paths from each other completely without an overlap. Clear interference fringes with a contrast of 67% have been observed using a monochromatic cold-neutron beam with a wavelength of 0.88 nm.

DOI： 10.1143/JPSJ.79.124201

Development of a triplet magnetic lens system to focus a pulsed neutron beam Reviewed

Takayuki Oku, Hiroshi Kira, Takenao Shinohara, Shin-ichi Takata, Masatoshi Arai, Jun-ichi Suzuki, Hirohiko M. Shimizu

INTERNATIONAL CONFERENCE ON NEUTRON SCATTERING 2009 Vol. 251 ( 1 ) 2010

Language：English Publishing type：Research paper (international conference proceedings) Publisher：IOP PUBLISHING LTD

A triplet magnetic lens system composed of three sextupole-magnets and two spin flippers was constructed to focus pulsed neutrons in a wide wavelength range with same focal lengths. In this study, we performed a pulsed neutron beam focusing experiment with the system. The design of the system and the experimental results are shown and discussed.

DOI： 10.1088/1742-6596/251/1/012078

Neutron Reflectometry for Observation of Machined Surface Roughness Reviewed

Kazuko Inoue, Tomoko Hirayama, Tomoki Uno, Toru Ebisawa, Kazuaki Ikeda, Hisayoshi Honda, Hirohiko Shimizu

JAPANESE JOURNAL OF APPLIED PHYSICS Vol. 48 ( 12 ) 2009.12

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOC APPLIED PHYSICS

Neutron reflectometry was applied for the characterization of machined roughness on iron surfaces, including a buried solid-solid contacting surface. The observed distribution of the reflected neutron beam could be explained using a structure factor estimated from the Fourier transform of the physical roughness measured by a contact-type roughness gauge, particularly in the case of a periodic surface structure. In the case of random roughness, the accumulation of beams specularly reflected from every small local region of the surface gave a better explanation of the broad distribution of the scattered beam, where each local region was assumed to be flat and differently inclined relative to the incident beam direction. When the surface was buried beneath another material, the width of the distribution of the reflected beam became slightly wider than that in air. Although neutron reflectometry for the characterization of surface roughness has various limitations, it is still an effective tool for nondestructively observing the surface roughness at a buried contacting surface. (C) 2009 The Japan Society of Applied Physics

DOI： 10.1143/JJAP.48.126504

Neutron interferometric search for short-range gravity Reviewed

Vladimir Gudkov, Geoffrey L. Greene, Hirohiko M. Shimizu

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT Vol. 611 ( 2-3 ) page： 153 - 156 2009.12

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV

We discuss the coherent nature of neutron interactions and properties of low-energy neutrons with the view of the possibility to search for "anomalous" forces with ranges from nuclear sizes up to the macroscopic scale. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.nima.2009.07.042

Highly polarized very cold neutrons through a permanent magnet quadrupole Reviewed

Kaoru Taketani, Kenji Mishima, Takashi Ino, Tamaki Yoshioka, Suguru Muto, Takahiro Morishima, Hirohiko M. Shimizu, Takayuki Oku, Junichi Suzuki, Takenao Shinohara, Kenji Sakai, Hiromi Sato, Katsuya Hirota, Yoshie Otake, Masaaki Kitaguchi, Masahiro Hino, Yoshichika Seki, Yoshihisa Iwashita, Masako Yamada, Masahiro Ichikawa, Takanori Sugimoto, Shinsuke Kawasaki, Sachio Komamiya, Yoshio Kamiya, Hidetoshi Otono, Satoru Yamashita, Peter Geltenbort

Physica B: Condensed Matter Vol. 404 ( 17 ) page： 2643 - 2645 2009.9

Publishing type：Research paper (scientific journal)

We obtained highly polarized very cold neutrons through a quadrupole magnet with a large aperture. When neutrons go through a quadrupole magnet, parallel-spin neutrons are attracted to the magnet axis and anti-parallel-spin neutrons are repelled off the axis. Therefore, the neutrons through a sufficiently long quadrupole magnet have completely parallel-spin. At the downstream of the quadrupole magnet, we placed another quadrupole magnet to divide neutrons into two regions depending on their spin directions. We obtained the neutron polarization from the integrated count of the two regions and found it was 99.88±0.09 (stat.)±0.05 (syst.)%. © 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2009.06.045

Development of modulating permanent magnet sextupole lens for focusing of pulsed cold neutrons Reviewed

Masako Yamada, Yoshihisa Iwashita, Masahiro Ichikawa, Takanori Sugimoto, Hiromu Tongu, Hiroshi Fujisawa, Hirohiko M. Shimizu, Takashi Ino, Kenji Mishima, Kaoru Taketani, Tamaki Yoshioka, Suguru Muto, Takahiro Morishima, Takayuki Oku, Jun ichi Suzuki, Takenao Shinohara, Kenji Sakai, Hiromi Sato, Katsuya Hirota, Yoshie Otake, Yoshichika Seki, Shinsuke Kawasaki, Sachio Komamiya, Yoshio Kamiya, Hidetoshi Otono, Satoru Yamashita, Peter Geltenbort

Physica B: Condensed Matter Vol. 404 ( 17 ) page： 2646 - 2651 2009.9

Publishing type：Research paper (scientific journal)

Modulating permanent magnet sextupole lens (PMSx) for focusing pulsed cold neutrons is under development. The synchronized modulation of its field gradient suppresses the chromatic aberration which arises from the Time Of Flight method. The strength of the magnetic field, the torque, and the rise of temperature during its operation are studied on a fabricated prototype. Experiments on focusing pulsed very cold neutrons (VCN) at ILL (Institute of Laue Langevin, France) were carried out and VCN with around λ=40 Å were focused by the PMSx at a focal length of about 0.5 m. The experimental results are presented in conjunction with the principle of the neutron focusing and the modulating method of the focal strength of permanent magnet lens with the double ring structure. © 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2009.06.132

Design of neutron beamline for fundamental physics at J-PARC BL05 Reviewed

Kenji Mishima, Takashi Ino, Kenji Sakai, Takenao Shinohara, Katsuya Hirota, Kazuaki Ikeda, Hiromi Sato, Yoshie Otake, Hitoshi Ohmori, Suguru Muto, Norio Higashi, Takahiro Morishima, Masaaki Kitaguch, Masahiro Hino, Haruhiko Funahashi, Tatsushi Shima, Jun-ichi Suzuki, Koji Niita, Kaoru Taketani, Yoshichika Seki, Hirohiko M. Shimizu

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT Vol. 600 ( 1 ) page： 342 - 345 2009.2

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV

A new beamline for a fundamental physics experiment is under construction at BL05 port in the Materials and Life Science Facility (MLF) at Japan Proton Accelerator Research Complex (J-PARC); this beamline is designed using novel techniques of neutron optics and it is termed "Neutron Optics and Physics." The beam from the moderator is deflected by multi-channel supermirrors and split into three branches for individual experiments. In this study, we have optimized the design of the beam optics and shields using the Monte Carlo simulation package PHITS. The neutron fluxes of beams are expected to be 9.2 x 10(5)/cm(2)/mu str/s/MW, 1.2 x 10(9)/cm(2)/s/MW, and 4.0 x 10(8)/cm(2)/s/MW, with polarization of 99.8%. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.nima.2008.11.087

Pulsed neutron beam control using a magnetic multiplet lens Reviewed

Takayuki Oku, Takenao Shinohara, Jun-ichi Suzuki, Roger Pynn, Hirohiko M. Shimizu

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT Vol. 600 ( 1 ) page： 100 - 102 2009.2

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV

As a magnetic neutron lens based on a sextupole magnet to focus neutrons has chromatic aberration, it has been proposed that the chromatic aberration can be compensated in the pulsed neutron beam focusing by combining the focusing and defocusing functions of the multiplet magnetic lens system synchronously with time-of-flight (TOF) of neutrons. In this study, we performed numerical simulations on the multiplet magnetic lens system to investigate how a pulsed neutron beam can be controlled on the basis of the TOF method. It was then confirmed that the chromatic aberration can be compensated and the focal condition can be maintained over a certain A-range by utilizing plural magnetic lenses in series and choosing the focusing and defocusing function of each magnetic lens synchronously with TOF of neutrons. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.nima.2008.11.055

A CCD-based Pixel Detector with Micron Spatial Resolution for Ultra Cold Neutrons Reviewed

Go Ichikawa, Shinsuke Kawasaki, Sachio Komamiya, Yoshio Kamiya, Tomoyuki Sanuki, Hirohiko M. Shimizu, Masahiro Hino, Masaaki Kitaguchi

2009 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-5 page： 1619 - + 2009

Language：English Publishing type：Research paper (international conference proceedings) Publisher：IEEE

We have developed a pixel detector for ultra-cold neutrons using a commercial CCD. In order to detect neutrons, a thin neutron converting layer is directly formed on the CCD surface. The detection efficiencies for cold, very-cold and ultra-cold neutrons are measured to be 1.7%, 4.05 +/- 0.08 +/- 0.12% and 40.6 +/- 0.7 +/- 2.8%, respectively. The spatial resolutions were measured to be 2.9 +/- 0.1 mu m for horizontal direction and 4.4 +/- 0.2 mu m for vertical direction. The vertical and horizontal directions are determined by the charge transfer mechanism of CCDs. The details of the pixel detector and its performance tests are described.

DOI： 10.1109/NSSMIC.2009.5402255

Slow Neutron Optics Reviewed

Hirohiko M. Shimizu

TRANSACTIONS OF THE MATERIALS RESEARCH SOCIETY OF JAPAN, VOL 33, NO 3 Vol. 33 ( 3 ) page： 541 - 545 2008

Language：English Publishing type：Research paper (international conference proceedings) Publisher：MATERIALS RESEARCH SOCIETY JAPAN-MRS-J

We survey the current status of reflective neutron optical devices, compound refractive and magnetic ones for enhancing the effectiveness of the beam utilization to extract physics information of samples.

Highly polarized cold neutron beam obtained by using a quadrupole magnet Reviewed

Takayuki Oku, Satoru Yamada, Takenao Shinohara, Jun-ichi Suzuki, Kenji Mishima, Katsuya Hirota, Hiromi Sato, Hirohiko M. Shimizu

PHYSICA B-CONDENSED MATTER Vol. 397 ( 1-2 ) page： 188 - 191 2007.7

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV

We performed a cold neutron polarization experiment using a polarization device based on a quadrupole magnet. By passing through the aperture of the quadrupole magnet, positive and negative polarity neutrons are accelerated in opposite directions and spatially separated due to the magnetic field gradient. Then, we extracted the one-spin component and analyzed the polarization degree by using a sextupole magnet and position-sensitive detector. As a result, very high neutron polarization degree P = 0.9993 +/- 0.0025 was obtained. Advantages of the quadrupole magnet as the neutron polarization device and its application to neutron scattering experiments are discussed. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2007.02.055

Moire Fringes in a Neutron Spin Interferometer

Taketani Kaoru, Seki Yoshichika, Funahashi Haruhiko, HINO Masahiro, KITAGUCHI Masaaki, OTAKE Yoshie, SHIMIZU Hirohiko M.

Journal of the Physical Society of Japan Vol. 76 ( 6 ) page： "64008 - 1"-"64008-7" 2007.6

Publisher：一般社団法人日本物理学会

We have revealed the criterion to observe moire fringes in a neutron spin interferometry. In former studies using wave front division, neutron beam had to be collimated by fine slits. On the other hand, we have succeeded to observe moire fringes with divergence angle of 8.3 mrad using spin polarization division. A model based on partial coherence theory has been developed and verified experimentally. These results will be the basis for neutron wave front manipulation technique using magnetic birefringence.

Moiré Fringes in a Neutron Spin Interferometer

Taketani Kaoru, Seki Yoshichika, Funahashi Haruhiko, Hino Masahiro, Kitaguchi Masaaki, Otake Yoshie, Shimizu Hirohiko M.

Journal of the Physical Society of Japan Vol. 76 ( 6 ) page： 064008 - 064008 2007.6

Language：English Publishing type：Research paper (scientific journal) Publisher：THE PHYSICAL SOCIETY OF JAPAN

We have revealed the criterion to observe moiré fringes in a neutron spin interferometry. In former studies using wave front division, neutron beam had to be collimated by fine slits. On the other hand, we have succeeded to observe moiré fringes with divergence angle of 8.3 mrad using spin polarization division. A model based on partial coherence theory has been developed and verified experimentally. These results will be the basis for neutron wave front manipulation technique using magnetic birefringence.

DOI： 10.1143/JPSJ.76.064008

Low energy particle detector using a superconducting transition edge sensor Reviewed

Masashi Ohno, Hiromi Sato, Kenji Mishima, Tokihiro Ikeda, Hirohiko M. Shimizu

IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY Vol. 17 ( 2 ) page： 328 - 331 2007.6

Language：English Publishing type：Research paper (scientific journal) Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Precise measurement of neutron beta decay tests predictions of the Standard Model of electroweak interaction. The coefficient a of the antineutrino/electron angular correlation is determined by measuring the energy spectrum of the recoil protons generated in the neutron beta decay. A proton spectrometer required for this measurement demands high detection efficiency, high energy resolution and a large detection area. We have begun development of a Transition Edge Sensor (TES) microcalorimeter for use as a low energy particle detector. To realize the large detection area we have designed a pixelated TES array incorporating a parallel biasing scheme. Our TES device consists of 4-pixels using a Au/Ti/Au trilayer film adjusted to a superconducting transition temperature of Tc similar to 380 mK. This temperature is convenient for use in a 3He cryostat with a pulse tube refrigerator. The Ail films improve thermal conductivity, thereby reducing position dependent effects and allow an increased detector area.

DOI： 10.1109/TASC.2007.898057

Wide-q observation from 10(-4) to 2.0 A(-1) using a focusing and polarized neutron small-angle scattering spectrometer, SANS-J-II Reviewed Open Access

Hiroki Iwase, Satoshi Koizumi, Jun-ichi Suzuki, Takayuki Oku, Hajime Sasao, Hirokazu Tanaka, Hirohiko M. Shimizu, Takeji Hashimoto

JOURNAL OF APPLIED CRYSTALLOGRAPHY Vol. 40 ( SUPPL. 1 ) page： S414 - S417 2007.4

Language：English Publishing type：Research paper (scientific journal) Publisher：BLACKWELL PUBLISHING

In order to extend an upper q-limit [q is the magnitude of the scattering vector q, defined by q = (4 pi/lambda)sin theta, where lambda and 2 theta are the wavelength and the scattering angle, respectively], high-angle He-3 sub-detectors were installed on a focusing and polarized neutron small-angle scattering spectrometer (SANS-J-II) at JRR-3, Tokai, Japan. Consequently, the upper q-limit was improved from 0.2 to 2.0 angstrom(-1). To quantitatively discriminate spin incoherent scattering from hydrogen or to perform nuclear spin polarization contrast variation, a remanent supermirror analyser is also available on the high-angle sub-detector. By combining a focusing ultra-small-angle scattering, realised by compound and/or magnetic lens and high-resolution area detector, SANS-J-II is able to cover from 3 x 10(-4) to 2.0 angstrom(-1) (four orders of magnitude of q), which benefits investigation of hierarchically ordered systems, found widely in hard, soft and bio-materials.

DOI： 10.1107/S0021889807006280

Focusing and polarized neutron small-angle scattering spectrometer (SANS-J-II). The challenge of observation over length scales from an angstrorm to a micrometre Reviewed Open Access

Satoshi Koizumi, Hiroki Iwase, Jun-ichi Suzuki, Takayuki Oku, Ryuhei Motokawa, Hajime Sasao, Hirokazu Tanaka, Daisuke Yamaguchi, Hirohiko M. Shimizu, Takeji Hashimoto

JOURNAL OF APPLIED CRYSTALLOGRAPHY Vol. 40 ( SUPPL. 1 ) page： S474 - S479 2007.4

Language：English Publishing type：Research paper (scientific journal) Publisher：BLACKWELL PUBLISHING

SANS-J (a pinhole small-angle neutron scattering spectrometer at research reactor JRR3, Tokai, Japan) was reconstructed as a focusing and polarized neutron small-angle scattering spectrometer (SANS-J-II). By employing focusing lenses of a biconcave MgF2 crystal or of a sextupole permanent magnet and a high-resolution photomultiplier, the minimum accessible magnitude of the scattering vector q(min) was improved from 3 x 10(-3) angstrom(-1) to an ultra-small-angle scattering (USAS) of 3 x 10(-4) angstrom(-1). Compared with a Bonse-Hart double-crystal method, the advantages of focusing USAS are the efficient detection of anisotropic USAS with an area detector, an improvement in q resolution Delta q/q at conventional magnitudes of the scattering vector q similar to 10(-3) angstrom(-1) and a gain in neutron flux in the conventional q region of q similar to 10(-3) angstrom(-1).

DOI： 10.1107/S0021889807014392

A focusing-geometry small-angle neutron scattering instrument with a magnetic neutron lens Reviewed Open Access

Takayuki Oku, Hiroki Iwase, Takenao Shinohara, Satoru Yamada, Katsuya Hirota, Satoshi Koizumi, Jun-ichi Suzuki, Takeji Hashimoto, Hirohiko M. Shimizu

JOURNAL OF APPLIED CRYSTALLOGRAPHY Vol. 40 ( SUPPL. 1 ) page： S408 - S413 2007.4

Language：English Publishing type：Research paper (scientific journal) Publisher：BLACKWELL PUBLISHING

We have constructed a focusing-geometry small-angle neutron scattering (FSANS) instrument, SANS-J-II, with two kinds of neutron focusing device: a series of compound refractive lenses made of MgF2 and a magnetic neutron lens based on an extended Halbach-type sextupole magnet. In this study, we investigated the performance of the FSANS instrument with the magnetic neutron lens. The intensity distribution of a direct neutron beam focused on the detector plane by the magnetic neutron lens had a ratio of the peak height to the background level of similar to 6 x 10(4) for a polarized neutron beam with a polarization degree of similar to 0: 99. It is found that a minimum value of the measurable q range [where q is the modulus of the scattering vector and is defined as q = (4 pi / lambda) sin(theta /2), where theta is the scattering angle and lambda is the neutron wavelength], q(min), of 6.5 x 10(-4) angstrom(-1) can be achieved by the FSANS instrument with the magnetic neutron lens using neutrons with lambda = 6.6 angstrom and Delta lambda/lambda = 0.13 for the full width at half maximum.

DOI： 10.1107/S0021889807003822

X-ray detection using superconducting tunnel junction shaped normal-distribution-function Reviewed

Tohru Taino, Tomohiro Nishihara, Koichi Hoshino, Hiroaki Myoren, Hiromi Sato, Hirohiko M. Shimizu, Susumu Takada

IEICE TRANSACTIONS ON ELECTRONICS Vol. E90C ( 3 ) page： 566 - 569 2007.3

Language：English Publishing type：Research paper (scientific journal) Publisher：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG

A normal-distribution-function-shaped superconducting tunnel junction (NDF-STJ) which consists of Nb/Al-AlOx/Al/Nb has been fabricated as an X-ray detector. Current - voltage characteristics were measured at 0.4 K using three kinds of STJs, which have the dispersion parameters sigma of 0.25, 0.45 and 0.75. These STJs showed very low subgap leakage current of about 5 nA. By irradiating with 5.9 keV X-rays, we obtained the spectrum of these NDF-STJs. They showed good energy resolution with small magnetic fields of below 3 mT, which is about one-tenth of those for conventional-shaped STJs.

DOI： 10.1093/ietele/e90-c.3.566

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