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

Abstract

Synchrotron-radiation based Mössbauer spectroscopy has become a useful technique capable for investigating various Mössbauer isotopes. For a typical experimental setup, the information associated with the pulse height (that is, energy) in an avalanche photodiode (APD) detector has not been used effectively. By using a system for simultaneous measurement system of time and energy associated with the APD signal, a system for the time- and energy-resolved Mössbauer spectroscopy has been developed. In this system, the pulse height information was converted to the time information through an amplitude-to-time converter applied to one of the divided signals from the APD. The corresponding time information was processed separately from another one of the divided signals. Both signals are recorded by a multi-channel scaler in an event-by-event data acquisition process. The velocity information from the Mössbauer transducer was also recorded as a tag for each signal event. Thus, the Mössbauer spectra with any time- and energy-window can be reconstructed after the data collection process. This system can be used for many purposes in time- and energy-resolved Mössbauer spectroscopy, and shows significant promise for use with other fast detectors and for various types of experiments.

DOI： 10.1088/1742-6596/2380/1/012136

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

We perform coincidence measurements between a particles and. rays from a U-233 source to determine the half-lives of the excited state in a Th-229 nucleus. We first prove that the half-lives of 42.43- and 164.53-keV states are consistent with literature values, whereas that of the 97.14-keV state [93(7) ps] deviates from a previously measured value [147(12) ps]. The half-lives of 71.83- and 163.25-keV states are determined for the first time. Based on the obtained half-lives and the Alaga rule, we estimate the radiative half-life of the low-energy isomeric state (Th-229m) to be 5.0(11) x 10(3) s, which is one of the key parameters for the frequency standard based on Th-229.

DOI： 10.1103/physrevc.104.024306

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Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevC.104.024306/fulltext

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Optical Society  

DOI： 10.1364/OE.424460

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of the Physical Society of Japan  

DOI： 10.7566/jpscp.33.011125

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

The rare decay KL was studied with the dataset taken at the J-PARC KOTO experiment in 2016, 2017, and 2018. With a single event sensitivity of (7.20±0.05stat±0.66syst)×10-10, three candidate events were observed in the signal region. After unveiling them, contaminations from K± and scattered KL decays were studied, and the total number of background events was estimated to be 1.22±0.26. We conclude that the number of observed events is statistically consistent with the background expectation. For this dataset, we set an upper limit of 4.9×10-9 on the branching fraction of KL→ π0ν ν at the 90% confidence level.

DOI： 10.1103/physrevlett.126.121801

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Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevLett.126.121801/fulltext

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

A pulse shape difference between photons and neutrons was observed in the output signals of scintillation light from the un-doped CsI calorimeter of the KOTO experiment for the KL→π0νν̄ decay. We developed a discrimination method to reject neutrons and to accept photons in the deposited energy range from 0.1 to 2 GeV. The method rejects 67% of neutron-induced single hadronic clusters and 86% of neutron-induced two-cluster events while keeping more than 90% of photon-induced single electromagnetic clusters and two-photon events.

DOI： 10.1016/j.nima.2020.164825

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：International Union of Crystallography (IUCr)  

This paper presents an absolute X-ray photon energy measurement method that uses a Bond diffractometer. The proposed system enables the prompt and rapid <italic>in situ</italic> measurement of photon energies over a wide energy range. The diffractometer uses a reference silicon single-crystal plate and a highly accurate angle encoder called SelfA. The performance of the system is evaluated by repeatedly measuring the energy of the first excited state of the potassium-40 nuclide. The excitation energy is determined as 29829.39 (6) eV, and this is one order of magnitude more accurate than the previous measurement. The estimated uncertainty of the photon energy measurement was 0.7 p.p.m. as a standard deviation and the maximum observed deviation was 2 p.p.m.

DOI： 10.1107/s1600577520014526

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

An electromagnetic calorimeter made of undoped CsI crystals is used in the J-PARC KOTO experiment to search for new physics beyond the standard model with the KL→π0νν̄ decay. The calorimeter is designed to operate in vacuum of 0.1 Pa and in a high-rate environment where the counting rate due to KL decays is O(100) kHz. A special method to calibrate the calorimeter during the data taking without using a tracking system for charged particles is reported. The energy, position, and timing resolutions of the calorimeter were evaluated in several beam tests, and the resolutions satisfy the required performance. The energy resolution with the total energy E is 0.66⊕1.81∕E[GeV]% in the inner region of the calorimeter.

DOI： 10.1016/j.nima.2020.164527

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

We study nearly degenerate four-wave mixing using a two-photon-allowed vibrational transition of parahydrogen. A signal photon is generated by a trigger photon and coherence among parahydrogen, which is prepared by two counterpropagating pump pulses, and we investigate the dependence of the signal pulse energy on the trigger frequency. The measured spectra depend on the geometry, shifting depending on the direction of the signal pulse and on the small angle formed by the counterpropagating pump pulses. Furthermore, we investigate the dependence of signal pulse energy on the incident time of the trigger pulse. The measured signal pulse energy is high if the trigger pulse is delayed slightly with respect to the pump pulses. We demonstrate that these geometry-dependent spectra and coherent-transient response can be explained by using simple models.

DOI： 10.1088/1361-6455/ab4a6e

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.7566/jpscp.27.012020

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

We developed a measurement system that enables the reconstruction of gamma-ray time spectra in cascade decay schemes with 0.3 ns time resolution, which is sufficient for nuclear decay with more than nanoseconds half-life. As this system records all the time and energy information of gamma-rays, the energy regions for the gamma-ray identification can be optimized after the measurement. Moreover, this system has five timing inputs and thus we can record the timing data of external perturbations; we can investigate the responses to the perturbation afterward. This property fulfills the demands required for quantum information research with gamma-rays. (C) 2019 The Japan Society of Applied Physics

DOI： 10.7567/1347-4065/ab3f19

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1038/s41586-019-1542-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

DOI： 10.1103/physrevlett.122.021802

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Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevLett.122.021802/fulltext

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

We observed two-photon emission (TPE) signal from the first vibrationally excited state of parahydrogen gas coherently excited by counter-propagating laser pulses. A single narrow-linewidth laser source has roles in the excitation of the parahydrogen molecules and the induction of the TPE process. We measured dependences of the signal energy on the detuning, target gas pressure, and input pulse energies. These results are qualitatively consistent with those obtained by numerical simulations based on Maxwell-Bloch equations with one spatial dimension and one temporal dimension. This study of the TPE process in the counterpropagating injection scheme is an important step toward neutrino mass spectroscopy.

DOI： 10.1088/1361-6455/aafbd0

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

This paper reports on the demonstration of a high-rate energy measurement technique using a thin depletion layer silicon avalanche photodiode (Si-APD). A dedicated amplitude-to-time converter is developed to realize simultaneous energy and timing measurement in a high rate condition. The energy response of the system is systematically studied by using monochromatic X-ray beam with an incident energy ranging from 6 to 33 keV. The obtained energy spectra contain clear peaks and tail distributions. The peak fraction monotonously decreases as the incident photon energy increases. This phenomenon can be explained by considering the distribution of the energy deposit in silicon, which is investigated by using a Monte Carlo simulation.

DOI： 10.1016/j.nima.2018.10.029

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society  

Nuclear resonant excitation and detection of its decay signal for the 26.27-keV level of Hg201 is demonstrated with high-brilliance synchrotron radiation (SR) and a fast x-ray detector system. This SR-based photonuclear excitation scheme, known as nuclear resonant scattering (NRS) in the field of materials science, is also useful for investigating nuclear properties, such as the half-lives and radiative widths of excited nuclear levels. To date, because of the limited time response of the x-ray detector, the nuclear levels to which this method could be applied have been limited to the one whose half-lives are longer than ∼1 ns. The faster time response of the NRS measurement makes possible NRS experiments on nuclear levels with much shorter half-lives. We have fabricated an x-ray detector system that has a time resolution of 56 ps and a shorter tail function than that reported previously. With the implemented detector system, the NRS signal of the 26.27-keV state of Hg201 could be clearly discriminated from the electronic scattering signal at an elapsed time of 1 ns after the SR pulse. The half-life of the state was determined as 629 ± 18 ps, which has better precision by a factor of three compared with that reported to date obtained from nuclear decay spectroscopy.

DOI： 10.1103/PhysRevC.97.024607

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

We report the coherent excitation of the vibrational state of hydrogen molecules by two-photon absorption and the resultant third-harmonic generation (THG). Parahydrogen molecules cooled by liquid nitrogen are irradiated by mid-infrared nanosecond pulses at 4.8 mu m with a nearly Fourier-transform-limited linewidth. The first excited vibrational state of parahydrogen is populated by two-photon absorption of the mid-infrared photons. Because of the narrow linewidth of the mid-infrared pulses, coherence between the ground and excited states is sufficient to induce higher-order processes. Near-infrared photons from the THG are observed at 1.6 mu m. The dependence of the intensity of the near-infrared radiation on mid-infrared pulse energy, target pressure, and cell length is determined. We used a simple formula for THG with consideration of realistic experimental conditions to explain the observed results.

DOI： 10.1088/1361-6455/aa9782

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

We investigate how the efficiency of coherently amplified two-photon emission depends on the frequency of one of the two emitted photons, namely the signal photon. This is done over the wavelength range of 5.048-10.21 mu m by using the vibrational transition of parahydrogen. The efficiency increases with the frequency of the signal photon. Considering experimental errors, our results are consistent with the theoretical prediction for the present experimental conditions. This study is an experimental demonstration of the frequency dependence of coherently amplified two-photon emission, and also presents its potential as a light source.

DOI： 10.1103/PhysRevA.96.063827

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

We propose a new scheme of producing an intense neutron beam whose yields may exceed those of the existing facilities by a few to several orders of magnitude in the sub-eV region. This scheme employs a MeV gamma beam extracted from circulating quantum ions, which has been recently proposed. The gamma beam is directed to a deuteron target and the photo-disintegration process generates a neutron beam. The calculated neutron energy spectrum is nearly flat down to the neV range, and thus there exists a possibility to utilize a good quality of neutrons especially in sub-eV energy region without using a moderator.

DOI： 10.1142/S0218301317500768

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER INST PHYSICS  

We developed a fast X-ray detector system for nuclear resonant scattering (NRS) experiments. Our system employs silicon avalanche photo-diode (Si-APD) as a fast X-ray sensor. The system is able to acquire both timing and energy of a single X-ray photon simultaneously in a high rate condition, 106 counts per second for one Si-APD. The performance of the system was investigated in SPring-8, a synchrotron radiation facility in Japan. Good time resolution of 120 ps (FWHM) was achieved with a slight tail distribution in the time spectrum by a level of 10(-9) at 1 ns apart from the peak. Using this system, we successfully observed the NRS from the 26.27-keV level of mercury-201, which has a half-life of 630(50) ps. We also demonstrated the reduction of background events caused by radioactive decays in a radioactive sample by discriminating photon energy. Published by AIP Publishing.

DOI： 10.1063/1.4989405

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

We report the observation of two-photon emission from a coherently excited vibrational state of solid parahydrogen, which is also a known quantum solid. Coherence between the ground and the excited states is prepared by stimulated Raman scattering using two visible laser pulses. The two-photon emission is triggered by another mid-infrared laser pulse. It was observed that the two-photon emission persists even when the trigger pulse is injected long after the excitation. This is due to the long decoherence time of the vibrational states of solid parahydrogen. It is found that the emission intensity increases even after the excitation pulses pass through the target completely. This coherence development is highly suppressed at high target temperatures and high residual orthohydrogen concentrations. Effects of target annealing and laser-induced damage on the target are also observed.

DOI： 10.1021/acs.jpca.7b02011

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

We report on the generation of nanosecond mid-infrared pulses having frequency tunability, a narrow linewidth, and a high pulse energy. These pulses are obtained by frequency mixing between injection-seeded near-infrared pulses in potassium titanyl arsenate crystals. A continuous-wave external cavity laser diode or a Ti:sapphire ring laser is used as a tunable seeding source for the near-infrared pulses. The typical energy of the generated mid-infrared pulses is in the range of 0.4-1mJ/pulse. The tuning wavelength ranges from 3142 to 4806 nm. A narrow linewidth of 1.4GHz and good frequency reproducibility of the mid-infrared pulses are confirmed by observing a rovibrational absorption line of gaseous carbon monoxide at 4587 nm. (C) 2017 The Japan Society of Applied Physics

DOI： 10.7567/JJAP.56.032101

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Other Link： http://orcid.org/0000-0001-8122-5145

Language：English   Publisher：OXFORD UNIV PRESS INC  

DOI： 10.1093/ptep/ptx001

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Other Link： http://orcid.org/0000-0001-8122-5145

Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：High Energy Accelerator Research Organization  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

We have developed a low-mass and high-efficiency charged-particle detector for an experimental study of the rare decay K-L -&gt; pi(0)nu(nu) over bar. The detector is important for suppressing the background with charged particles to the level below the signal branching ratio predicted by the Standard Model (O(10(-11))). The detector consists of two layers of 3mm thick plastic scintillators with embedded wavelength-shifting fibers and multi-pixel photon counters for the readout. We manufactured the counter and evaluated the performance in terms of light yield, timing resolution, and efficiency. With this design, we achieved an inefficiency per layer against penetrating charged particles of less than 1.5 x 10(-5), which satisfies the requirement of the KOTO experiment determined from simulation studies.

DOI： 10.1093/ptep/ptv191

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

The KOTO(K-0 at Tokai) experiment aims to observe the CP-violating rare decay K-L -&gt; pi(0) nu(nu) over bar by using a long-lived neutral-kaon beam produced by the 30 GeV proton beam at the Japan Proton Accelerator Research Complex. The K-L flux is an essential parameter for the measurement of the branching fraction. Three K-L neutral decay modes, K-L -&gt; 3 pi(0), K-L -&gt; 2 pi(0), and K-L -&gt; 2 gamma, were used to measure the K-L flux in the beam line in the 2013 KOTO engineering run. A Monte Carlo simulation was used to estimate the detector acceptance for these decays. Agreement was found between the simulation model and the experimental data, and the remaining systematic uncertainty was estimated at the 1.4% level. The K-L flux was measured as (4.183 +/- 0.017(stat.) +/- 0.059(sys.)) x 10(7) K-L per 2 x 10(14) protons on a 66-mm-long Au target.

DOI： 10.1093/ptep/ptv171

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

SPAN (SPectroscopy of Atomic Neutrino) project aims to determine the absolute neutrino mass. The process we plan to use is a cooperative de-excitation of atoms in a metastable level emitting a neutrino pair associated with a photon. The photon energy spectrum of this process contains information on the absolute mass of neutrino. Key items of this experiment are a rate amplification using macro-coherence in a target medium in case of plural particles emission and an external triggering of the emission in order to scan the spectrum. We have demonstrated the rate amplification in two-photon emission from para-hydrogen gas which was coherently excited to its first vibrationally excited state. The coherence in the medium was generated by irradiating two driving laser pulses. The emission was stimulated by irradiating a mid-infrared laser pulse. The enhancement factor of more than 10(18) with respect to the spontaneous emission was achieved. This paper briefly summarizes the results.

DOI： 10.1088/1742-6596/718/6/062043

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.71.2.0_577

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.71.2.0_528

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

We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10(15) from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect.

DOI： 10.1007/s10751-015-1177-1

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

The Outer-Edge Veto (OEV) counter subsystem for extra-photon detection from the backgrounds for the K-L(0) -&gt; pi(0) nu(nu) over bar decay is located at the outer edge of the endcap Csl calorimeter of the KOTO experiment at JPARC. The subsystem is composed of 44 counters with different cross-sectional shapes. All counters are made of lead and scintillator plates and read out through wavelength-shifting fibers. In this paper, we discuss the design and performances of the OEV counters under heavy load (similar to 8 tons/m(2) in vacuum. For 1-MeV energy deposit, the average light yield and time resolution are 20.9 photo-electrons and 1.5 ns, respectively. Although no pronounced peak by minimum-ionizing particles is observed in the energy distributions, an energy calibration method with cosmic rays works well in monitoring the gain stability with an accuracy of a few percent. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.nima.2015.05.036

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

We report on coherent enhancement of two-photon emission from the excited vibrational state of molecular hydrogen triggered by irradiating mid-infrared pulses externally. We previously observed the two-photon emission triggered by the internally generated fourth Stokes photons. By injecting independent mid-infrared pulses externally, it is possible to control the experimental parameters and investigate the mechanism in more detail. In this article, we describe the two-photon emission using the external trigger pulses. Its spectrum and dependence on the energy and timing of the trigger pulse are presented along with numerical simulations based on the Maxwell-Bloch equations. The measured number of emitted photons is 6 x 10(11) photons/pulse and the resulting enhancement factor from the spontaneous emission is more than 10(18). This value is three orders of magnitude higher than that of the previous experiment. External control of the emission process is expected to be essential for observation of the weaker process of radiative emission of a neutrino pair.

DOI： 10.1093/ptep/ptv103

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

We describe a novel multi-GeV photon detector which operates under an intense flux of neutrons. It is composed of lead-aerogel sandwich counter modules. Its salient features are high photon detection efficiency and blindness to neutrons. Monte Carlo (MC) simulations show that the efficiency for photons with energy larger than 1 GeV is expected to be higher than 99.5% and that for 2 GeV/c neutrons is less than 1%. Performance of photon detection with an underlying large flux of neutrons was measured by a partial detector with 12 modules. We confirm the efficiency for photons with energy &gt; 1 GeV is consistent with the MC expectation within an uncertainty of 8.2%.

DOI： 10.1093/ptep/ptv074

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

The performance of the Csl electromagnetic calorimeter to be used for the J-PARC E14 KOTO experiment for a rare decay K-L --&gt; pi(0)nu(nu) over bar was studied by using a positron beam from an accelerator. The energy, timing, and position resolutions for energies up to 800 NieV were measured. We also developed a new method to reconstruct the incident angle of photons based on the shower shape recorded with the calorimeter, and evaluated the method to suppress possible backgrounds for K-L --&gt; pi(0)nu(nu) over bar decay signals. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.nima.2015.02.046

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Language：Japanese   Publisher：The Physical Society of Japan (JPS)  

DOI： 10.11316/jpsgaiyo.70.1.0_668

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Language：Japanese   Publisher：The Physical Society of Japan (JPS)  

DOI： 10.11316/jpsgaiyo.70.1.0_86

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

In this paper, we describe an experiment which was conducted to explore the macro-coherent amplification mechanism using a two-photon emission process from the first vibrationally excited state of the para-hydrogen molecule. Large coherence in the initial state was prepared by the adiabatic Raman method, and the lowest Stokes sideband was used as a trigger field. We observed coherent two-photon emission consistent with the expectation of the Maxwell-Bloch equation derived for the process, whose rate is larger by many orders of magnitude than that of spontaneous emission.

DOI： 10.1093/ptep/ptu152

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

We developed a high voltage system for the electromagnetic calorimeter of the KOTO detector. The system is designed around a low noise, low power Cockcroft-Walton (CW) photomultiplier tube base with a high gain preamplifier. The low power makes it suitable for operations in vacuum. The low noise and high gain allow detecting signals in the 1 MeV range. We achieved a final noise level below 180 mu Vrms, for a preamplifier gain of more than 40. A vacuum tolerant control system for the CW bases power distribution was also designed. This system is able to control and monitor the high voltage of each individual base. (c) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.nima.2014.02.007

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

We describe the K-L(0) flux measurements performed at the J-PARC neutral-kaon beam line. This beam line was constructed for an experiment aiming to observe the CP-violating rare decay K-L(0) -&gt; pi(0)nu(nu) over bar The primary proton energy was 30 GeV and the K-L(0) production angle was 16 degrees. Prior to the physics run, the flux and spectrum were measured by counting K-L(0) -&gt; pi(+)pi(-)pi(0) decays with a simple setup, which was composed of an electromagnetic calorimeter and a hodoscope system. Results from these measurements are presented and compared with various hadron-interaction simulations. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.nima.2011.11.010

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

We developed a novel beam profile monitor for measuring the shape of an intense neutral beam for particle physics. This monitor is based on a detector technology of scintillating fibers, photomultiplier tubes, and sampling ADCs. It has an advantage for its simplicity, reliability, flexibility, and versatility. This monitor was installed in the small-diameter neutral beam for the K-L(0) -> pi(0)nu(nu) over bar experiment at J-PARC. We report in this article the development and performance of this monitor. (C) 2011 The Japan Society of Applied Physics

DOI： 10.1143/JJAP.50.036701

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Authorship：Lead author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：一般社団法人 日本物理学会  

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Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

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Language：English   Publishing type：Rapid communication, short report, research note, etc. (bulletin of university, research institution)   Publisher：RIKEN Nishina Center for Accelerator-Based Science  

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Authorship：Lead author   Language：English   Publishing type：Article, review, commentary, editorial, etc. (bulletin of university, research institution)  

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：日本光学会  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (bulletin of university, research institution)  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：日本アイソトープ協会  

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Language：Japanese   Publishing type：Rapid communication, short report, research note, etc. (scientific journal)  

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Event date： 2023.4.15

Language：Japanese   Presentation type：Poster presentation  

Venue：ザ・プリンス 京都宝ヶ池  

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Event date： 2023.3.2 - 2023.3.4

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Nagoya University  

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Event date： 2023.2.13 - 2023.2.17

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Event date： 2022.12.15 - 2022.12.16

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Event date： 2022.7.17 - 2022.7.22

Language：English   Presentation type：Poster presentation  

Venue：Tronto  

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Event date： 2022.3.7

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：Spring-8  

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Event date： 2021.12.16 - 2021.12.17

Language：Japanese  

Venue：名古屋大学、オンライン併用  

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Event date： 2021.9.14 - 2021.9.17

Language：Japanese   Presentation type：Symposium, workshop panel (public)  

Venue：オンライン  

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Event date： 2021.5.31 - 2021.6.4

Language：English   Presentation type：Poster presentation  

Venue：online  

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Event date： 2021.3.12 - 2021.3.15

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：online  

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Event date： 2020.9.14 - 2020.9.17

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

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Event date： 2020.6.1 - 2020.6.5

Language：English   Presentation type：Poster presentation  

Venue：Virtual  

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Event date： 2020.2.19 - 2020.2.21

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：理化学研究所神戸キャンパス  

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Event date： 2020.2.17 - 2020.2.19

Language：English   Presentation type：Poster presentation  

Venue：Kashiwa Campus, The university of Tokyo  

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Language：Japanese   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

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Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：岡山大学津島キャンパス  

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Language：English  

Venue：UCLA, Department of Physics and Astronomy, Hudson' lab  

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Language：English   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：online (RIKEN)  

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Language：English   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：Northwestern University  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：山形大学  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学伊都キャンパス  

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Language：English   Presentation type：Oral presentation (general)  

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Language：English   Presentation type：Oral presentation (invited, special)  

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Language：English   Presentation type：Poster presentation  

Venue：Tokyo University, Tokyo, JAPAN  

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Language：English   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学野田キャンパス  

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Language：English   Presentation type：Oral presentation (general)  

Venue：Atlanta, U.S.A.  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪大学豊中キャンパス  

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Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Kyoto University, Kyoto, Japan  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：宮崎大学木花キャンパス  

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Language：English   Presentation type：Poster presentation  

Venue：Seoul, KOREA  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北学院大学泉キャンパス  

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Language：English   Presentation type：Oral presentation (general)  

Venue：Trin, Italy  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：早稲田大学早稲田キャンパス  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：長野県 北安曇郡 白馬村 岳美山荘  

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Language：English   Presentation type：Poster presentation  

Venue：Takamatsu, JAPAN  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：佐賀大学本庄キャンパス  

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Language：English   Presentation type：Poster presentation  

Venue：Washignton DC  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東海大学  

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Language：Japanese   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：岡山大学  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：高知大学  

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Language：English   Presentation type：Oral presentation (invited, special)  

Venue：University of Michigan, Ann Arbor, Illinois, U.S.A.  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：広島大学  

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Language：English   Presentation type：Poster presentation  

Venue：Kyoto University, Kyoto, Japan  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都産業大学  

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Language：English   Presentation type：Poster presentation  

Venue：Kyoto University, Kyoto, Japan  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都大学  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：弘前大学  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：弘前大学  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州工業大学  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岡山大学  

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Language：English   Presentation type：Poster presentation  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：甲南大学  

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Language：English   Presentation type：Poster presentation  

Venue：Kobe University, Kobe, Japan  

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Language：English   Presentation type：Poster presentation  

Venue：EPOCAL, Tsukuba, Ibaraki  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：立教大学  

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Language：English   Presentation type：Poster presentation  

Venue：EPOCAL, Tsukuba, Ibaraki  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：長野県 北安曇郡 白馬村 岳美山荘  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：山形大学  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：近畿大学  

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Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北海道大学  

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Author：Other 

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Author：Other 

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Author：Other 

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Author：Other 

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Author：Other 

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Author：Other 

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Author：Other 

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