| 研究課題/領域番号 |
19H00669
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| 研究機関 | 国立研究開発法人量子科学技術研究開発機構 |
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研究代表者 |
PIROZHKOV Alex 国立研究開発法人量子科学技術研究開発機構, 関西光科学研究所 光量子科学研究部, 上席研究員 (00446410)
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| 研究分担者 |
Esirkepov Timur 国立研究開発法人量子科学技術研究開発機構, 関西光科学研究所 光量子科学研究部, 上席研究員 (10370363)
匂坂 明人 国立研究開発法人量子科学技術研究開発機構, 関西光科学研究所 光量子科学研究部, 主幹研究員 (20354970)
小倉 浩一 国立研究開発法人量子科学技術研究開発機構, 関西光科学研究所 光量子科学研究部, 主幹研究員 (30354971)
Pikuz Tatiana 大阪大学, 先導的学際研究機構, 特任准教授(常勤) (20619978)
難波 愼一 広島大学, 先進理工系科学研究科(工), 教授 (00343294)
Koga James 国立研究開発法人量子科学技術研究開発機構, 関西光科学研究所 光量子科学研究部, 専門業務員 (70370393)
桐山 博光 国立研究開発法人量子科学技術研究開発機構, 関西光科学研究所 光量子科学研究部, グループリーダー (40354972)
神門 正城 国立研究開発法人量子科学技術研究開発機構, 関西光科学研究所 光量子科学研究部, 次長 (50343942)
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| 研究期間 (年度) |
2019-04-01 – 2024-03-31
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| キーワード | Coherent x-ray source / New imaging paradigm / BISER / Relativistic plasma / Plasma singularities |
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| 研究実績の概要 |
During the 2nd Project year, we continued the active development of experimental methods and diagnostics necessary to accomplish the Project Goals. We also achieved several important research results:
We published results of our PIC simulations demonstrating a method to detect relativistic plasma singularities, which is a core optical diagnostics necessary for this Project [Esirkepov et al., Phys. Plasmas 27 052103 (2020)]. We also performed theoretical studies and simulations of various singularities of relativistic plasmas [Mu et al., Physical Review E 102 053202 (2020)].
We published two papers devoted to another core diagnostics of this Project, x-ray spectroscopy and spectroscopic instruments [Ryazantsev et al., Crystals 11 130 (2021)]; [Ragozin et al., Physics-Uspekhi 191 522 (2021)].
We further improved our J-KAREN-P laser which is used for majority of this Project's experiments. The laser performance is summarized in [Kiriyama et al., Crystals 10, 783 (2020)].
We performed a very successful experiment on BISER generation and diagnostics. In particular, we for the first time obtained data on the material dependence of BISER: the BISER brightness is similar in He and H2, while it is significantly suppressed in Ne; we also obtained data with mixed gases. Further, we improved our optical imaging of relativistic plasma and observed features with dimensions as small as 2 um; work is now in progress to connect these to plasma singularities.
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| 現在までの達成度 (区分) |
現在までの達成度 (区分)
2: おおむね順調に進展している
理由
We continued active development of experimental methods & diagnostics necessary to accomplish the Project Goals. Method (L): Laser Control (Co-I: Hiromitsu Kiriyama): We improved various aspects of laser operations and parameters which resulted in brighter and more stable BISER generation.
Method (O): High-Resolution Optical Diagnostics (Co-Is: Koichi Ogura, Masaki Kando). We implemented optical imaging, "Top View", with ~2 um resolution and obtained rich images of relativistic plasma. We also achieved similar spatial resolution in the optical probing operating it in the Shadowgraph mode.
Method (X): X-ray Diagnostics (Co-Is: Akito Sagisaka, Tatiana Pikuz, Shinichi Namba, RC: Masato Koike). We performed a major modification of our experimental Target Chamber and installed a newly-developed Magnetic Bottle Electron Spectrometer (MBES). BISER radiation was focused to the MBES chamber, where it produced Auger electrons in Xe; these electrons were recorded by the MBES's ToF detector and we obtained the first signal, although the S/N ratio was low. We acquired super-polished substrates for the high-resolution Varied-Line-Space (VLS) diffraction grating optimized for our experimental setup and the 1-2 keV spectral range. Due to COVID-19, we could not order the grating manufacturing, which became the task for the next year.
Theory & Simulations (Co-Is: Timur Esirkepov, James Koga): We showed that a Schlieren method with ~10 fs probe pulse can be used to detect the relativistic plasma singularities. We simulated the gas flow through supersonic nozzles used in experiments.
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| 今後の研究の推進方策 |
The new coronavirus emphasized the importance of our Goals, namely future attosecond lensless imaging, which potentially will result in quick imaging of unknown viruses. In FY2020, COVID-19 caused delays with equipment, but this was not too bad.
In accordance to the Project Plan and Goals, we will continue the Methods & Diagnostics development: (O): High-Resolution Optical Diagnostics (Co-Is: Koichi Ogura, Masaki Kando): we will improve the 2nd critical diagnostics, high-resolution optical probe, and operate it in the Schlieren mode (it was Shadow till now).
Method (X): X-ray Diagnostics (Co-Is: Akito Sagisaka, Tatiana Pikuz, Shinichi Namba, RC: Masato Koike). We plan to acquire the new optimized VLS grating for 1-2 keV range. We will take into account experience of the FY2020 experiment and improve the Photoelectron and Auger MBES beamline throughput to significantly increase the S/N ratio.
Theory & Simulations (Co-Is: Timur Esirkepov, James Koga): We will continue PIC simulations for guiding the methods development and experiments. We will perform gas dynamic simulations for our nozzle.
We plan to perform two experiments, one with the Astra laser (UK), and another with our J-KAREN-P laser. We will employ the Methods and Diagnostics developed earlier and plan to achieve the Filamentation and Self-Focusing control and detect the singularities with new optical diagnostics, and correlate their properties with BISER radiation.
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