English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present a new method for the measurements of photonuclear reactionflux-weighted average cross sections and isomeric ratios using a laser-drivenbremsstrahlung $\gamma$-ray source. An ultra-bright ultra-fast60$\,\thicksim\,$250 MeV bremsstrahlung $\gamma$-ray source was establishedusing the 200 TW laser facility in the Compact Laser Plasma AcceleratorLaboratory, Peking University, which could cover the energy range from knockingout neutrons to producing pions. Stable quasi-monoenergetic electron beams weregenerated via laser wakefield acceleration with a charge of300$\,\thicksim\,$600 pC per shot. The averaged $\gamma$-ray intensities($\geqslant$8 MeV) were higher than 10$^{8}$ per shot and the instantaneousintensities can reach above 10$^{19}$ s$^{-1}$ with a duration time about 6.7ps. $^{65}$Cu($\gamma,\,n$)$^{64}$Cu and $^{27}$Al($\gamma,\,x$)$^{24}$Nareactions were used as $\gamma$-ray flux monitors in the experiments. Theflux-weighted average cross sections and isomeric ratios of$^{197}$Au($\gamma,\,xn;\,x\,=\,1\thicksim9$) reactions were analyzed throughactivation measurements. The results showed good agreement with previous worksand proved this method to be accurate. The$^{197}$Au($\gamma,\,xn;\,x\,=\,7\thicksim\,9$) reaction cross sections werefirst achieved with the highest threshold energy of 71.410 MeV. Theoreticalcross sections of TALYS 1.9 were calculated to compare with experiment results.This method offered a unique way of gaining insight into photonuclear reactionresearch, especially for short-lived isomers which extremely lack experimentaldata.

$^{197}$Au($\gamma,\,xn;\,x\,=\,1\thicksim9$) Reaction Cross Section Measurements using Laser-Driven Ultra-Intense $\gamma$-Ray Source