A 125MeV electron linac has been constructed at Laboratory for Electron Beam Research and Applica... more A 125MeV electron linac has been constructed at Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University for Free Electron Laser (FEL) and Parametric X-ray (PXR)[1] generation. Electron bunches of 3 4 psec width formed at the injector are compressed to within 1 psec during passing through the magnetic bunching system. Peak current of the electron beam injected to the FEL system is expected to be about 50 A. FEL lasing has been achieved at the wavelength range from 0.9 to 6 μm. Estimated peak power of the extracted FEL light pulse is about 4 MW. Applied researches using the FEL started last autumn. Preliminary experiment for the PXR generation has been proceeded. First light of the PXR is observed at April in this year .
... Sato Yukie; School of Dentistry, Nihon University at Matsudo. Okada Hiroyuki; School of Denti... more ... Sato Yukie; School of Dentistry, Nihon University at Matsudo. Okada Hiroyuki; School of Dentistry, Nihon University at Matsudo. Yamamoto Hirotsugu; ... Nihon University. Hayakawa Ken; Nihon University. Sato Isamu; Nihon University. 本文を読む／探す. ...
Development of the high intensity compact X-rays equipment aims to picturize imaging of the soft ... more Development of the high intensity compact X-rays equipment aims to picturize imaging of the soft tissue of a living body at a speed of one sheet per second. The last purpose of the development is to perform radiotherapy of the cancer by coherent monochrome X-rays. In order to attain this purpose, the source of X-rays and an accelerator are based
ABSTRACT We have successfully transported subterahertz-wave (sub-THz-wave) coherent synchrotron r... more ABSTRACT We have successfully transported subterahertz-wave (sub-THz-wave) coherent synchrotron radiation (CSR) from an accelerator room to an experimental room by using an existing IR free-electron laser (FEL) beamline at the Laboratory for Electron Beam Research and Application at Nihon University. The power of the transported CSR was 50 nJ per macropulse, and it was available at frequencies of 0.1–0.3 THz. From two-dimensional imaging performed with the sub-THz-wave CSR, metallic structures concealed by plastic in a smart card were nondestructively detected at a spatial resolution of 1.4 mm. We also verified the existence of hydrated water in a crystal by using chemometric two-band spectroscopy with the sub-THz-wave CSR and IR FEL. Pioneering applications, such as more reliable material identification, can be anticipated from this complex light source composed from the sub-THz-wave CSR and IR FEL beams.
Transactions of Japanese Society for Medical and Biological Engineering
Phase-contrast imaging based on a novel X-ray source, parametric X-ray radiation (PXR), has been ... more Phase-contrast imaging based on a novel X-ray source, parametric X-ray radiation (PXR), has been studied at the Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University. The PXR was generated by the 100 MeV electron beam incident on a Si single crystal. The quasi-monochromatic X-rays in the 5 to 34 keV range were used for the imaging experiments. The phase-contrast imaging method is appropriate for imaging of the soft tissues in biological materials, since it is effective for improving the low-contrast property in the standard absorption-contrast imaging of materials which have low X-ray absorption coefficients. Diffraction enhanced imaging (DEI) method was employed as the phase contrast imaging technique. Computed tomograms for a biological organ were obtained from the DEI data taken in 90 different orientations. Particular properties of PXR, i.e. compact facility, large X-ray beam irradiation field of approximately 100 mm in diameter and quasi-monochromati...
This paper describes the project of remote telescope systems developed by Wakayama University and... more This paper describes the project of remote telescope systems developed by Wakayama University and Misato Observatory. This includes the first version that could broadcast live pictures of stars, and the second version that will support interesting GUI and a dome.
The X-ray beam from the parametric X-ray radiation (PXR) generator system at the Laboratory for E... more The X-ray beam from the parametric X-ray radiation (PXR) generator system at the Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University has been applied to the wavelength dispersive X-ray absorption fine structure (DXAFS) measurement. Difference in the spectral resolution of the X-ray absorption near edge structure (XANES) has been investigated in terms of the incident electron beam position on the PXR target crystal plate which had a partly wedge-shaped cross-section with symmetric plane on one side and asymmetric plane on the other. The result has shown a dependence of the resolution on the incident electron beam position. The FWHM of the diffraction curve at the second crystal has simultaneously changed, which means that the energy definition of the PXR beam has been dependent on the incident electron beam position; the spectral resolution of XANES has been improved at the position where the FWHM was narrow.
The parametric X-ray radiation (PXR) generator at the Laboratory for Electron Beam Research and A... more The parametric X-ray radiation (PXR) generator at the Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University is composed of a double-crystal system to keep an identical direction of the X-ray output independent of energy range. Since the X-ray beam from the PXR generator system has a good spatial coherence and linear energy dispersion with narrow line width, wavelength dispersive X-ray absorption fine structure (DXAFS) measurement and phase-contrast imaging are expected as promising applications of PXR. The monochromatic X-ray beam in the energy region from 5 to 20 keV has been provided to users' experiments by using a Si(111) crystal as the PXR target. Recently the X-rays with energies up to 33 keV were obtained by using a Si(220) crystal. With a larger energy dispersion of the PXR beam from the Si(220) crystal as compared with the case of Si(111), a higher spectral resolution has been obtained in the X-ray absorption near edge structure (XANES) spect...
Radioactivity of the cooling water circulating the 125-MeV linac in operation has been measured a... more Radioactivity of the cooling water circulating the 125-MeV linac in operation has been measured at LEBRA in Nihon University in terms of positron annihilation γ-rays resulted from β + decays of 15 O nuclei. The dose equivalent at 10 cm from the surface of the reservoir tank in the precise water temperature controller has been deduced to be higher than the limit allowed by the radiation hazard protection law. Currently the controller is placed in the accelerator room, which is not good taking account of radiation damage and daily maintenance. However, the result suggests that a necessary measure must be taken to lower the dose when the controller is moved to the modulator room.
Precise experiments using FEL and PXR require a high-stability electron beam from the linac. The ... more Precise experiments using FEL and PXR require a high-stability electron beam from the linac. The cooling water temperature for an accelerator tube and electromagnets has been adjusted with high precision by a refrigerator and improvement of a fine cooling system, and modify of a flow path. The linac cooling water temperature has been controlled to within ±0.01 by adjustment and the improvement of the fine cooling water system. Fluctuation of the PXR intensity at the output port has been suppressed to ±2% by improvement of the cooling water system.
Operation time of the 125-MeV electron linac was approximately 2000 hours in 2010 at the Laborato... more Operation time of the 125-MeV electron linac was approximately 2000 hours in 2010 at the Laboratory for Electron Beam Research and Application in Nihon University, serving total of 1400 hours of beam time for users' experiments. In addition to conventional full-beam acceleration, a burst-beam acceleration mode was implemented in the renewed electron gun system. The x-ray intensity in the parametric x-ray radiation beam has been measured using thin-wall ion chambers developed for in-line monitoring.
International Journal of Oral-Medical Sciences, 2005
The ablation effect of laser treatment of dental tissues is mainly determined by: i) wavelength, ... more The ablation effect of laser treatment of dental tissues is mainly determined by: i) wavelength, ii) power fluence, and iii) pulse structure. To evaluate the effect of pulse structure, the 2.94 μm free electron laser (FEL) and the Er: YAG laser were used to ...
ABSTRACT A novel X‐ray source based on Parametric X‐ray radiation (PXR) has been employed for pha... more ABSTRACT A novel X‐ray source based on Parametric X‐ray radiation (PXR) has been employed for phase‐contrast imaging at the Laboratory for Electron Beam Research and Application (LEBRA), Nihon University, Japan. The PXR X‐rays were generated by the 100 MeV electron beam passing through a Si single crystal. The X‐rays in the 16∼34 keV range were chosen for imaging of biological samples. The quasi‐monochromatic, tunable, and coherent X‐ray source is appropriate for this application. In addition, the large X‐ray beam irradiation field of approximately 100 mm in diameter, which was achieved without special optics, suggests that the PXR is applicable to imaging for medical diagnostics.
A 125MeV electron linac has been constructed at Laboratory for Electron Beam Research and Applica... more A 125MeV electron linac has been constructed at Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University for Free Electron Laser (FEL) and Parametric X-ray (PXR)[1] generation. Electron bunches of 3 4 psec width formed at the injector are compressed to within 1 psec during passing through the magnetic bunching system. Peak current of the electron beam injected to the FEL system is expected to be about 50 A. FEL lasing has been achieved at the wavelength range from 0.9 to 6 μm. Estimated peak power of the extracted FEL light pulse is about 4 MW. Applied researches using the FEL started last autumn. Preliminary experiment for the PXR generation has been proceeded. First light of the PXR is observed at April in this year .
... Sato Yukie; School of Dentistry, Nihon University at Matsudo. Okada Hiroyuki; School of Denti... more ... Sato Yukie; School of Dentistry, Nihon University at Matsudo. Okada Hiroyuki; School of Dentistry, Nihon University at Matsudo. Yamamoto Hirotsugu; ... Nihon University. Hayakawa Ken; Nihon University. Sato Isamu; Nihon University. 本文を読む／探す. ...
Development of the high intensity compact X-rays equipment aims to picturize imaging of the soft ... more Development of the high intensity compact X-rays equipment aims to picturize imaging of the soft tissue of a living body at a speed of one sheet per second. The last purpose of the development is to perform radiotherapy of the cancer by coherent monochrome X-rays. In order to attain this purpose, the source of X-rays and an accelerator are based
ABSTRACT We have successfully transported subterahertz-wave (sub-THz-wave) coherent synchrotron r... more ABSTRACT We have successfully transported subterahertz-wave (sub-THz-wave) coherent synchrotron radiation (CSR) from an accelerator room to an experimental room by using an existing IR free-electron laser (FEL) beamline at the Laboratory for Electron Beam Research and Application at Nihon University. The power of the transported CSR was 50 nJ per macropulse, and it was available at frequencies of 0.1–0.3 THz. From two-dimensional imaging performed with the sub-THz-wave CSR, metallic structures concealed by plastic in a smart card were nondestructively detected at a spatial resolution of 1.4 mm. We also verified the existence of hydrated water in a crystal by using chemometric two-band spectroscopy with the sub-THz-wave CSR and IR FEL. Pioneering applications, such as more reliable material identification, can be anticipated from this complex light source composed from the sub-THz-wave CSR and IR FEL beams.
Transactions of Japanese Society for Medical and Biological Engineering
Phase-contrast imaging based on a novel X-ray source, parametric X-ray radiation (PXR), has been ... more Phase-contrast imaging based on a novel X-ray source, parametric X-ray radiation (PXR), has been studied at the Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University. The PXR was generated by the 100 MeV electron beam incident on a Si single crystal. The quasi-monochromatic X-rays in the 5 to 34 keV range were used for the imaging experiments. The phase-contrast imaging method is appropriate for imaging of the soft tissues in biological materials, since it is effective for improving the low-contrast property in the standard absorption-contrast imaging of materials which have low X-ray absorption coefficients. Diffraction enhanced imaging (DEI) method was employed as the phase contrast imaging technique. Computed tomograms for a biological organ were obtained from the DEI data taken in 90 different orientations. Particular properties of PXR, i.e. compact facility, large X-ray beam irradiation field of approximately 100 mm in diameter and quasi-monochromati...
This paper describes the project of remote telescope systems developed by Wakayama University and... more This paper describes the project of remote telescope systems developed by Wakayama University and Misato Observatory. This includes the first version that could broadcast live pictures of stars, and the second version that will support interesting GUI and a dome.
The X-ray beam from the parametric X-ray radiation (PXR) generator system at the Laboratory for E... more The X-ray beam from the parametric X-ray radiation (PXR) generator system at the Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University has been applied to the wavelength dispersive X-ray absorption fine structure (DXAFS) measurement. Difference in the spectral resolution of the X-ray absorption near edge structure (XANES) has been investigated in terms of the incident electron beam position on the PXR target crystal plate which had a partly wedge-shaped cross-section with symmetric plane on one side and asymmetric plane on the other. The result has shown a dependence of the resolution on the incident electron beam position. The FWHM of the diffraction curve at the second crystal has simultaneously changed, which means that the energy definition of the PXR beam has been dependent on the incident electron beam position; the spectral resolution of XANES has been improved at the position where the FWHM was narrow.
The parametric X-ray radiation (PXR) generator at the Laboratory for Electron Beam Research and A... more The parametric X-ray radiation (PXR) generator at the Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University is composed of a double-crystal system to keep an identical direction of the X-ray output independent of energy range. Since the X-ray beam from the PXR generator system has a good spatial coherence and linear energy dispersion with narrow line width, wavelength dispersive X-ray absorption fine structure (DXAFS) measurement and phase-contrast imaging are expected as promising applications of PXR. The monochromatic X-ray beam in the energy region from 5 to 20 keV has been provided to users' experiments by using a Si(111) crystal as the PXR target. Recently the X-rays with energies up to 33 keV were obtained by using a Si(220) crystal. With a larger energy dispersion of the PXR beam from the Si(220) crystal as compared with the case of Si(111), a higher spectral resolution has been obtained in the X-ray absorption near edge structure (XANES) spect...
Radioactivity of the cooling water circulating the 125-MeV linac in operation has been measured a... more Radioactivity of the cooling water circulating the 125-MeV linac in operation has been measured at LEBRA in Nihon University in terms of positron annihilation γ-rays resulted from β + decays of 15 O nuclei. The dose equivalent at 10 cm from the surface of the reservoir tank in the precise water temperature controller has been deduced to be higher than the limit allowed by the radiation hazard protection law. Currently the controller is placed in the accelerator room, which is not good taking account of radiation damage and daily maintenance. However, the result suggests that a necessary measure must be taken to lower the dose when the controller is moved to the modulator room.
Precise experiments using FEL and PXR require a high-stability electron beam from the linac. The ... more Precise experiments using FEL and PXR require a high-stability electron beam from the linac. The cooling water temperature for an accelerator tube and electromagnets has been adjusted with high precision by a refrigerator and improvement of a fine cooling system, and modify of a flow path. The linac cooling water temperature has been controlled to within ±0.01 by adjustment and the improvement of the fine cooling water system. Fluctuation of the PXR intensity at the output port has been suppressed to ±2% by improvement of the cooling water system.
Operation time of the 125-MeV electron linac was approximately 2000 hours in 2010 at the Laborato... more Operation time of the 125-MeV electron linac was approximately 2000 hours in 2010 at the Laboratory for Electron Beam Research and Application in Nihon University, serving total of 1400 hours of beam time for users' experiments. In addition to conventional full-beam acceleration, a burst-beam acceleration mode was implemented in the renewed electron gun system. The x-ray intensity in the parametric x-ray radiation beam has been measured using thin-wall ion chambers developed for in-line monitoring.
International Journal of Oral-Medical Sciences, 2005
The ablation effect of laser treatment of dental tissues is mainly determined by: i) wavelength, ... more The ablation effect of laser treatment of dental tissues is mainly determined by: i) wavelength, ii) power fluence, and iii) pulse structure. To evaluate the effect of pulse structure, the 2.94 μm free electron laser (FEL) and the Er: YAG laser were used to ...
ABSTRACT A novel X‐ray source based on Parametric X‐ray radiation (PXR) has been employed for pha... more ABSTRACT A novel X‐ray source based on Parametric X‐ray radiation (PXR) has been employed for phase‐contrast imaging at the Laboratory for Electron Beam Research and Application (LEBRA), Nihon University, Japan. The PXR X‐rays were generated by the 100 MeV electron beam passing through a Si single crystal. The X‐rays in the 16∼34 keV range were chosen for imaging of biological samples. The quasi‐monochromatic, tunable, and coherent X‐ray source is appropriate for this application. In addition, the large X‐ray beam irradiation field of approximately 100 mm in diameter, which was achieved without special optics, suggests that the PXR is applicable to imaging for medical diagnostics.
Uploads
Papers by Toshinari Tanaka