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Burst Intensification by Singularity Emitting Radiation (BISER) is a new mechanism of bright coherent x-ray generation employing high-power femtosecond lasers to drive singularities of multi-stream relativistic plasma flows. We have recently demonstrated that the BISER source can be controlled and stabilized with a tailored plasma density profile (density jump), which is created with a blade inserted into the supersonic gas flow. In this presentation we report on new experimental results obtained with the upgraded J-KAREN-P laser. In particular, we extended the BISER emission up to keV photon energies, and increased the BISER yield in the 60 to 100 eV spectral range up to ~ 1 uJ (10^11 photons) per pulse into the detector acceptance angle of 10^-2 sr., The 11th International Conference of Inertial Fusion Sciences and Applications (IFSA-2019)

Recently we successfully demonstrated controllable BISER in experiments with the J-KAREN-P laser using blade-induced shocks in supersonic gas jets. This resulted in significant improvement of the BISER source stability. Furthermore, the controllable BISER technique made an important breakthrough in the coherent x-ray source performance: the emission extended up to the keV spectral region. Additionally, the soft x-ray and XUV photon yield enhanced by orders of magnitude. In particular, we demonstrated a pulse with up to 1 uJ energy (10^11 photons) in the 60-100 eV spectral range within a 10^-2 sr acceptance angle., VII International Conference "Frontiers of Nonlinear Physics"

We describe new experimental results obtained with the recently upgraded J-KAREN-P laser. The controllable BISER technique enabled us the demonstration of an important breakthrough in the coherent x-ray source performance: the x-ray source position was stabilized, and the emission extended up to the keV spectral region. Additionally, the photon yield enhanced by an order of magnitude resulting in up to 1 µJ pulse (10^11 photons) in the 60-100 eV spectral range within a 10^-2 sr acceptance angle., OPTO-2019

In the last two decades the regime of ultraintense (>10^19 Wcm-2) laser pulses producing and interacting with plasma has revealed unprecedented advancements in particle accelerations and as a secondary source of high-energy radiation beams. Previous experiments, developed in our group, have discovered coherent x-ray beams with high brightness (approaching that of FELs) and composed of multiple high order harmonics. The following experiments and simulations have shown that the produced x-ray sources are from tens to hundreds of nanometers in size. This novel phenomenon is known as BISER. Here, we report new experimental results concerning spatial distribution of these promising x-ray sources, which will enable a more rigorous understanding of the underpinning physics of its origin and the effect of specific laser parameters on its spatial pattern and brightness. We thank the J-KAREN-P laser operation group. We acknowledge financial support from JSPS JP 25390135, JP 26707031, SP18104, and QST Director Funds Sousei #16 and #20., Optics & Photonics International Congress 2019 (OPIC)

We describe new experimental results obtained with the recently upgraded J-KAREN-P laser, including this BISER control technique. We achieved break-through in the BISER coherent x-ray source performance, detected the BISER emission in the keV spectral region, and obtained an order of magnitude enhancement of the photon yield resulted in up to 1uJ pulse, 10^11 photons in the 60-100 eV spectral range within a 10^-2 sr acceptance angle., The 74th JPS Annual Meeting

We present new experimental results on the BISER control technique obtained with the J-KAREN-P laser at the power of 150 TW. We extended the BISER emission up to the keV spectral region and obtained an order of magnitude enhancement of the photon yield (up to 1 uJ pulse, 10^11 photons in the 60-100 eV spectral range within a 10^-2 sr acceptance angle)., The 66th JSAP Spring Meeting

We introduce a new approach to temporally resolve ultrafast micron-scale processes via the use of a multi-channel optical probe. We demonstrate that this technique enables highly precise time-resolved, two-dimensional spatial imaging of intense laser pulse propagation dynamics, plasma formation and laser beam filamentation within a single pulse over four distinct time frames. The design, development and optimization of the optical probe system is presented, as are representative experimental results from the first implementation of the multi-channel probe with a high-power laser pulse interaction with a helium gas jet target.

In the last two decades the regime of ultraintense (>1019 Wcm-2) laser pulses producing and interacting with plasma has revealed unprecedented advancements in particle acceleration and as a secondary source of high-energy radiation beams. Previous experiments, developed in our group, have discovered coherent x-ray beams with high brightness (approaching that of FELs1) and composed of multiple high order harmonics2,3. The following experiments and simulations have shown that the produced x-ray sources are from tens to hundreds of nanometers in size. This novel phenomenon is known as BISER4. Here, we report new experimental results concerning spatial distribution of these promising x-ray sources, which will enable a more rigorous understanding of the underpinning physics of its origin and the effect of specific laser parameters on its spatial pattern and brightness. Additionally, a potential alternative technique to measure their spatial distribution with a few hundred nanometers resolution is presented, which will enable both, the estimation of the source size and its brightness. [1] C. Pellegrini and J. Stohr, Nucl. Instrum. Meth. A, 500, 33-40, 2003. [2] A. S. Pirozhkov et al., Physical Review Letters, 108, 135004, 2012. [3] A. S. Pirozhkov et al., New Journal of Physics, 16, 093003, 2014. [4] A. S. Pirozhkov, T. Esirkepov et al., Scientific Reports, 7, 17968, 2017., 第2回QST国際シンポジウムに参加

Fruit firmness estimates usually require contacting or destructive methods. However, we propose to estimate firmness from an all optical, non-contacting method that generates and detects elastic waves in an apple. The compressional and shear wave velocities are governed by the fruit's elastic constants and density, which can be used to estimate firmness, non-destructively. High energy pulses of light are used to excite elastic waves via thermo-elastic expansion. Elastic waves are detected using a laser Doppler vibrometer. By exciting the apple surface at many locations we accurately estimate the compressional, shear and Rayleigh wave velocities of an apple. Repeated realizations of this experiment over 15 days to observe changes in apple elastic properties over time. Softening of the apple decreases the resonant mode frequencies and elastic constants, as well as increases wave attenuation. We find that attenuation is the most sensitive parameter to the aging of the apple. We believe that our novel method of apple interrogation could be automated, and extended to other fruits.

There are many health and economic consequences for patients with osteopenia, the precursor to osteoporosis. A range of treatments may provide positive outcomes for otherwise healthy adults, including dietary and exercise approaches, either alone or in combination. The primary aim of this systematic review was to evaluate the effect of dietary approaches (including diet alone, diet with dietary supplements, both with or without physical activity intervention) on bone mineral density (BMD) to treat adults aged ≥18 years who were classified as having osteopenia. Six databases (Ovid MEDLINE including Ovid Medline in process, Cochrane Library, EMBASE, CINAHL Plus, Web of Science and Scopus) were searched systematically to identify randomised controlled trials of dietary approaches to treat osteopenic adults published from 1994 to November 2014. Study eligibility was determined, and included studies were assessed for risk of bias. Outcome data, particularly the primary outcomes of BMD T- and Z-scores or other measures of bone density, were combined narratively. The searches yielded 3511 papers, with three studies fulfilling the inclusion criteria. These studies included 254 participants, all free-living post-menopausal females with confirmed osteopenia. Vitamin D interventions were tested in all included studies, with none showing significant differences between intervention and placebo groups on BMD. This review has identified a lack of evidence to guide clinical practice in this area. Opportunities exist for future research to determine the effect of nonpharmacological approaches to osteopenia treatment in healthy populations, especially research that considers younger-aged and male populations, physical activity, habitual dietary intake and key bone health nutrients. yes