IBIC2012 - List of Authors (Aoyama, M.)

Paper

Title

Page

The First Electron Bunch Measurement by means of DAST Organic EO Crystals

29

Y. Okayasu, S. Matsubara, T. Togashi
JASRI/SPring-8, Hyogo-ken, Japan
M. Aoyama
JAEA/Kansai, Kyoto, Japan
A. Iwasaki, S. Owada
The University of Tokyo, Tokyo, Japan
T. Matsukawa
RIKEN ASI, Sendai, Miyagi, Japan
H. Minamide
RIKEN Advanced Science Insititute, Sendai, Miyagi, Japan
K. Ogawa, T. Sato, H. Tomizawa
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
E. Takahashi
RIKEN, Saitama, Japan

Pilot user experiments via the seeded FEL have been demonstrated at the Prototype Test Accelerator (VUV-FEL), SPring-8 from July, 2012. A precise measurement of the electron bunch charge distribution (BCD) is crucial key to keep spatial and temporal overlaps between high-order harmonic (HH) laser pulses and electron bunches. R&D of the 3D-BCD monitor with a single-shot detection has been extensively promoted at SPring-8. The monitor adopts a spectral decoding based Electro-Optic (EO) sampling technique that is non-destructive and enables real-time reconstruction of the 3D-BCD with a temporal resolution of 30- to 40-fs (FWHM). So far, such EO sampling based BCD monitors have been developed by utilizing inorganic EO crystals such as ZnTe and their temporal resolutions are limited to ~130 fs (FWHM). As a part of this project, the first BCD measurement with an organic EO crystal DAST has been successfully demonstrated at the facility. Signal intensities, temporal resolutions and radiation related issues via both ZnTe and DAST are discussed.

Slides MOCC03 [3.912 MB]

MOPA49

EO-sampling-based Temporal Overlap Control System for an HH Seeded FEL

176

S. Matsubara
RIKEN/SPring-8, Hyogo, Japan
M. Aoyama
JAEA/Kansai, Kyoto, Japan
A. Iwasaki, S. Owada
The University of Tokyo, Tokyo, Japan
K. Ogawa, T. Sato, H. Tomizawa
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
Y. Okayasu, T. Togashi, T. Watanabe
JASRI/SPring-8, Hyogo-ken, Japan
E. Takahashi
RIKEN, Saitama, Japan

FELs have greatly interested for the short-wavelength region. However, their temporal profile and frequency spectra have shot-to-shot fluctuation by a SASE process. One of the promising approached for the problems is a seeded FEL scheme by using a full-coherent light source. The seeded FEL has been demonstrated in the EUV region by employ the high-order harmonics (HH) generation from an external laser source at the SCSS test-accelerator in the SPring-8. It is important for the HH-seeded FEL scheme to synchronize and overlap between the seeding laser pulse and the electron bunch. Their timing difference and laser spatial pointing is drifting. Therefore, a timing feedback and non-destructive monitor are necessary to operate seeded FEL continuously. We have constructed the timing monitor based on Electro-Optic (EO) sampling which is measure the timing difference the seeded laser pulse and the electron bunch simultaneously with the seeded FEL process. The probe laser pulse for the EO-sampling system is optically split from the common external HH laser driver for the seeded FEL. The EO-sampling system is able to use timing feedback for continual operation of the HH-seededFEL.

Paper	Title	Page
MOCC03	The First Electron Bunch Measurement by means of DAST Organic EO Crystals	29
	Y. Okayasu, S. Matsubara, T. Togashi JASRI/SPring-8, Hyogo-ken, Japan M. Aoyama JAEA/Kansai, Kyoto, Japan A. Iwasaki, S. Owada The University of Tokyo, Tokyo, Japan T. Matsukawa RIKEN ASI, Sendai, Miyagi, Japan H. Minamide RIKEN Advanced Science Insititute, Sendai, Miyagi, Japan K. Ogawa, T. Sato, H. Tomizawa RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan E. Takahashi RIKEN, Saitama, Japan
	Pilot user experiments via the seeded FEL have been demonstrated at the Prototype Test Accelerator (VUV-FEL), SPring-8 from July, 2012. A precise measurement of the electron bunch charge distribution (BCD) is crucial key to keep spatial and temporal overlaps between high-order harmonic (HH) laser pulses and electron bunches. R&D of the 3D-BCD monitor with a single-shot detection has been extensively promoted at SPring-8. The monitor adopts a spectral decoding based Electro-Optic (EO) sampling technique that is non-destructive and enables real-time reconstruction of the 3D-BCD with a temporal resolution of 30- to 40-fs (FWHM). So far, such EO sampling based BCD monitors have been developed by utilizing inorganic EO crystals such as ZnTe and their temporal resolutions are limited to ~130 fs (FWHM). As a part of this project, the first BCD measurement with an organic EO crystal DAST has been successfully demonstrated at the facility. Signal intensities, temporal resolutions and radiation related issues via both ZnTe and DAST are discussed.
	Slides MOCC03 [3.912 MB]

MOPA49	EO-sampling-based Temporal Overlap Control System for an HH Seeded FEL	176
	S. Matsubara RIKEN/SPring-8, Hyogo, Japan M. Aoyama JAEA/Kansai, Kyoto, Japan A. Iwasaki, S. Owada The University of Tokyo, Tokyo, Japan K. Ogawa, T. Sato, H. Tomizawa RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan Y. Okayasu, T. Togashi, T. Watanabe JASRI/SPring-8, Hyogo-ken, Japan E. Takahashi RIKEN, Saitama, Japan
	FELs have greatly interested for the short-wavelength region. However, their temporal profile and frequency spectra have shot-to-shot fluctuation by a SASE process. One of the promising approached for the problems is a seeded FEL scheme by using a full-coherent light source. The seeded FEL has been demonstrated in the EUV region by employ the high-order harmonics (HH) generation from an external laser source at the SCSS test-accelerator in the SPring-8. It is important for the HH-seeded FEL scheme to synchronize and overlap between the seeding laser pulse and the electron bunch. Their timing difference and laser spatial pointing is drifting. Therefore, a timing feedback and non-destructive monitor are necessary to operate seeded FEL continuously. We have constructed the timing monitor based on Electro-Optic (EO) sampling which is measure the timing difference the seeded laser pulse and the electron bunch simultaneously with the seeded FEL process. The probe laser pulse for the EO-sampling system is optically split from the common external HH laser driver for the seeded FEL. The EO-sampling system is able to use timing feedback for continual operation of the HH-seededFEL.