| Paper | Title | Page |
|---|---|---|
| WEPRO050 | Cryogenically Cooled 1J, ps Yb:YAG Slab Laser for High-brightness Laser-Compton X-Ray Source | 2056 |
|
||
|
Funding: This work benefitted from the support of the Czech Republic’s Ministry of Education, Youth and Sports to the HiLASE and DPSSLasers projects cofinanced from the European Regional Development Fund. Laser Compton X-ray source is studied as an accelerator-laser hybrid technology to realize a compact source from soft X-ray to gamma ray*. It is critical to design a solid state laser of 1J pulse energy with 1ps pulse length, and a high beam quality for 10 microμm diameter interaction. The required M2 is less than 1.5 in a standard normal incidence configuration. X-ray total photon number is ~109 with 1nC, 3ps 43MeV electron bunch for each shot. HiLASE project is committed to make a progress in the field of new generation solid state laser based on Yb-doped materials, to deliver 1J at 120Hz of 1-2ps with M2<1.5. The laser system consists of a seed fiber laser and two amplifier stages, an Yb:YAG thin disk regenerative amplifier, and a cryogenically cooled single slab booster amplifier. We have obtained output energy of 45mJ from the regenerative amplifier at 1 kHz with M2 <1.2. Booster amplifier is designed by a conduction cooling to build a compact system. Gain bandwidth was 1.2nm at 120K, enough to obtain 1-2ps pulses. Improvement of the crystal holder and the experimental results are presented to indicate the available pulse energy and M2. *Endo, A. et.al. “Characterization of the monochromatic laser Compton X-ray beam with picosecond and femtosecond pulse widths”, Proceedings SPIE 4502, pp100-108 (2001) |
||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO050 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| MOPRI039 | Ultra-short Electron Bunch Generation using Energy-chirping Cell Attached RF Electron Gun | 685 |
|
||
|
Funding: Work supported by JSPS Grant-in-Aid for Young Scientists (B) 23740203 and Scientific Research (A) 10001690 We have been developing an Energy-Chirping-Cell attached RF electron gun (ECC-RF-Gun) for generating ultra-short electron bunches. ECC-RF-Gun has extra cell at the end of gun cavity in order to chirp the bunch energy. Such a bunch can be compressed by the velocity difference though the drift space. We have already installed it to our accelerator system and successfully observed a coherent synchrotron/transition radiation at 0.3THz. It is clear that the bunch length was short enough to generate 0.3THz, which corresponds to less than 500fs bunch length was achieved if we assume the gaussian shape. In this conference, the principle of ECC-RF-Gun, the recent results of bunch length measurement and future prospective will be presented. |
||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI039 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| WEPRO116 | Direct High Power Laser Diagnostic Technique Based on Focused Electron Bunch | 2242 |
|
||
|
In laser produced plasma EUV source, high intensity pulse CO2 laser is essential for plasma generation. To achieve high conversion efficiency and stable EUV power, we desire to measure laser profile in collision point. However, focused laser profile has not been observed directory by existing techniques. We have been developing laser profiler based on laser Compton scattering. Laser profile can be measured by scanning focused electron beam while measuring Compton scattering signal. This method is suitable for a high intensity laser, but very small spot size of electron beam is required. To achieve small spot size, we use S-band photocathode rf gun and special design solenoid lens. The beam size was simulated by General particle tracer (GPT) and directory measured by Gafchromic film HD-810. We have succeeded in observing minimum beam size of about 20 μm rms. We are preparing beam scanning system, pulse CO2 laser and a detector for Compton signal. In this conference, we will report the results of focused electron beam measurement and future prospective.
Work supported by NEDO(New Energy and Industrial Technology Development Organization). |
||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO116 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| THPME133 | Bunch Length Measurement with 2-Cell RF-Deflector at Waseda University | 3556 |
|
||
|
We have been studying on a system to measure the length of electron bunch generated by a photocathode rf electron gun at Waseda University. We adopted the rf-deflector system which can convert the longitudinal distribution to transverse by sweeping the electron bunch. By using HFSS, we optimized the design of the 2 cell rf-deflector which is operating on π-mode, dipole (TM110-like) mode at 2856 MHz. The fabrication and the tuning of the rf deflector have successfully processed. We have installed the rf-deflector in the accelerator system of Waseda University, and performed the measurement of the bunch length. It is confirmed that this rf-deflector has the temporal resolution of 167fs with 700kW supply when the beam energy is 4.8MeV. This means that our rf-deflector system has possibility to measure the ultra-short bunch length. In this conference, the rf-deflector system in Waseda University, the result of the bunch length measurement, the performance of the rf-deflector and the future plan will be reported.
Work supported by JSPS Grant-in-Aid for Scientific Research (A) 10001690 and the Quantum Beam Technology Program of MEXT. |
||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME133 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |