Stacking fault energy analyses of additively manufactured stainless steel 316L and CrCoNi medium entropy alloy using in situ neutron diffraction

Woo, W.*; Jeong, J.-S.*; Kim, D.-K.*; Lee, C. M.*; Choi, S.-H.*; Suh, J.-Y.*; Lee, S. Y.*; Harjo, S.; Kawasaki, Takuro

Scientific Reports (Internet), 10(1), p.1350_1 - 1350_15, 2020/01

https://doi.org/10.1038/s41598-020-58273-3

Battery-free, skin-interfaced microfluidic/electronic systems for simultaneous electrochemical, colorimetric, and volumetric analysis of sweat

Bandodkar, A. J.*; Gutruf, P.*; Choi, J.*; Lee, K.-H.*; Sekine, Yurina; Reeder, J. T.*; Jeang, W. J.*; Aranyosi, A. J.*; Lee, S. P.*; Model, J. B.*; et al.

Science Advances (Internet), 5(1), p.eaav3294_1 - eaav3294_15, 2019/01

https://doi.org/10.1126/sciadv.aav3294

Interest in advanced wearable technologies increasingly extends beyond systems for biophysical measurements to those that enable continuous, non-invasive monitoring of biochemical markers in biofluids. Here, we introduce battery-free, wireless microelectronic platforms that perform sensing via schemes inspired by the operation of biofuel cells. Combining these systems in a magnetically releasable manner with chrono-sampling microfluidic networks that incorporate assays based on colorimetric sensing yields thin, flexible, lightweight, skin-interfaced technologies with broad functionality in sweat analysis. A demonstration device allows simultaneous monitoring of sweat rate/loss, along with quantitative measurements of pH and of lactate, glucose and chloride concentrations using biofuel cell and colorimetric approaches.

Projection imaging with directional electron and proton beams emitted from an ultrashort intense laser-driven thin foil target

Nishiuchi, Mamiko; Choi, I. W.*; Daido, Hiroyuki; Nakamura, Tatsufumi*; Pirozhkov, A. S.; Yogo, Akifumi*; Ogura, Koichi; Sagisaka, Akito; Orimo, Satoshi; Daito, Izuru*; et al.

Plasma Physics and Controlled Fusion, 57(2), p.025001_1 - 025001_9, 2015/02

https://doi.org/10.1088/0741-3335/57/2/025001

Projection images of a metal mesh produced by directional MeV electron beam together with directional proton beam, emitted simultaneously from a thin foil target irradiated by an ultrashort intense laser. The mesh patterns are projected to each detector by the electron beam and the proton beam originated from tiny virtual sources of 20 micron meter and 10 micron meter diameters, respectively. Based on the observed quality and magnification of the projection images, we estimate sizes and locations of the virtual sources for both beams and characterize their directionalities. To carry out physical interpretation of the directional electron beam qualitatively, we perform 2D particle-in-cell simulation which reproduces a directional escaping electron component, together with a non-directional dragged-back electron component, the latter mainly contributes to building a sheath electric field for proton acceleration.

Atomic structure of two-dimensional binary surface alloys; Si(111)- superstructure

Fukaya, Yuki; Matsuda, Iwao*; Hashimoto, Mie*; Kubo, Keisuke*; Hirahara, Toru*; Yamazaki, Shiro*; Choi, W. H.*; Yeom, H. W.*; Hasegawa, Shuji*; Kawasuso, Atsuo; et al.

Surface Science, 606(11-12), p.919 - 923, 2012/06

https://doi.org/10.1016/j.susc.2012.02.006

no abstracts in English

Event structure and double helicity asymmetry in jet production from polarized collisions at = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Y.*; Al-Bataineh, H.*; Alexander, J.*; Aoki, K.*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review D, 84(1), p.012006_1 - 012006_18, 2011/07

https://doi.org/10.1103/PhysRevD.84.012006

We report on the event structure and double helicity asymmetry () of jet production in longitudinally polarized collisions at = 200 GeV. Photons and charged particles were measured by the PHENIX experiment. Event structure was compared with the results from PYTHIA event generator. The production rate of reconstructed jets is satisfactorily reproduced with the next-to-leading-order perturbative QCD calculation. We measured = -0.0014 0.0037 at the lowest bin and -0.0181 0.0282 at the highest bin. The measured is compared with the predictions that assume various distributions.

Azimuthal correlations of electrons from heavy-flavor decay with hadrons in and Au+Au collisions at = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

https://doi.org/10.1103/PhysRevC.83.044912

Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.

Status and result of the KSTAR upgrade for the 2010's campaign

Yang, H. L.*; Kim, Y. S.*; Park, Y. M.*; Bae, Y. S.*; Kim, H. K.*; Kim, K. M.*; Lee, K. S.*; Kim, H. T.*; Bang, E. N.*; Joung, M.*; et al.

Proceedings of 23rd IAEA Fusion Energy Conference (FEC 2010) (CD-ROM), 8 Pages, 2011/03

http://www-naweb.iaea.org/napc/physics/FEC/FEC2010/html/node436.htm#84701

Because the 2010 operation of Korea Superconducting Tokamak Advanced Research (KSTAR) mainly aims to achieve strongly elongated and diverted plasma, all the necessary hardware systems to provide an essential circumstance for the plasma shaping were newly installed and upgraded in 2010. In this paper, general configuration of the upgraded systems described earlier will be outlined. Moreover, several key performances and test results of the systems will be also reported in summary.

Focusing and spectral enhancement of a repetition-rated, laser-driven, divergent multi-MeV proton beam using permanent quadrupole magnets

Nishiuchi, Mamiko; Daito, Izuru; Ikegami, Masahiro; Daido, Hiroyuki; Mori, Michiaki; Orimo, Satoshi; Ogura, Koichi; Sagisaka, Akito; Yogo, Akifumi; Pirozhkov, A. S.; et al.

Applied Physics Letters, 94(6), p.061107_1 - 061107_3, 2009/02

https://doi.org/10.1063/1.3078291

A pair of conventional permanent magnet quadrupoles is used to focus a 2.4 MeV laser-driven proton beam at a 1 Hz repetition rate. The magnetic field strengths are 55 T/m and 60 T/m for the first and second quadrupoles respectively. The proton beam is focused to a spot size (full width at half maximum) of 2.78 mm at a distance of 650 mm from the source. This result is in good agreement with a Monte Carlo particle trajectory simulation.

Protons and electrons generated from a 5-m thick copper tape target irradiated by s-, circularly-, and p-polarized 55-fs laser pulses

Li, Z.*; Daido, Hiroyuki; Fukumi, Atsushi*; Bulanov, S. V.; Sagisaka, Akito; Ogura, Koichi; Yogo, Akifumi; Nishiuchi, Mamiko; Orimo, Satoshi; Mori, Michiaki; et al.

Physics Letters A, 369(5-6), p.483 - 487, 2007/10

https://doi.org/10.1016/j.physleta.2007.05.010

The energy spectra of energetic protons emitted in the normal direction from a 5-m thick copper tape irradiated by p-, circularly-, and s-polarized 55-fs laser pulses with intensity of 8-910W/cm are measured together with the angular distribution and energy spectra of hot electrons by the target normal direction. The protons with energy up to 1.34 MeV in the rear target normal direction and hot electrons in the laser propagation direction are found. The characters of protons and electrons driven by the circularly-polarized irradiation are close to that driven by the p-polarized one, which is much different from the case at laser intensity of 2-310W/cm.

Laser prepulse dependency of proton-energy distributions in ultraintense laser-foil interactions with an online time-of-flight technique

Yogo, Akifumi; Daido, Hiroyuki; Fukumi, Atsushi*; Li, Z.*; Ogura, Koichi; Sagisaka, Akito; Pirozhkov, A. S.; Nakamura, Shu*; Iwashita, Yoshihisa*; Shirai, Toshiyuki*; et al.

Physics of Plasmas, 14(4), p.043104_1 - 043104_6, 2007/04

https://doi.org/10.1063/1.2721066

Fast protons are observed by a newly-developed time-of-flight spectrometer, which provides proton-energy distributions immediately after the irradiation of a laser pulse having an intensity of W/cm onto a 5-m-thick copper foil. The maximum proton energy is found to increase when the intensity of a fs-prepulse arriving 9 ns before the main pulse increases from 10 to 10 W/cm. Interferometric measurement indicates that the preformed-plasma expansion at the front surface is smaller than 15 m, which corresponds to the spatial resolution of the diagnostics. This sharp gradient of the plasma makes a beneficial effect on increasing the absorption efficiency of the main-pulse energy, resulting in the increase in the proton energy. This is supported by the result that the X-ray intensity from the laser plasma clearly increases with the prepulse intensity.