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

Ion acceleration from gaseous targets driven by relativistic-intensity laserswas demonstrated as early as the late 90s, yet most of the experimentsconducted to date have involved picosecond-duration, Nd:glass lasers operatingat low repetition rate. Here, we present measurements on the interaction ofultraintense ($\sim 10^{20}\,\rm W\,cm^{-2}$, 1 PW), ultrashort ($\sim 70\,\rmfs$) Ti:Sa laser pulses with near-critical ($\sim 10^{20}\,\rm cm^{-3}$) heliumgas jets, a debris-free targetry compatible with high ($\sim 1\,\rm Hz$)repetition rate operation. We provide evidence of $\alpha$ particles beingforward accelerated up to $\sim 2.7\,\rm MeV$ energy with a total flux of $\sim10^{11}\,\rm sr^{-1}$ as integrated over $>0.1 \,\rm MeV$ energies and detectedwithin a $0.5\,\rm mrad$ solid angle. We also report on on-axis emission ofrelativistic electrons with an exponentially decaying spectrum characterized bya $\sim 10\,\rm MeV$ slope, i.e., five times larger than the standardponderomotive scaling. The total charge of these electrons with energy above 2MeV is estimated to be of $\sim 1 \,\rm nC$, corresponding to $\sim 0.1\,\%$ ofthe laser drive energy. In addition, we observe the formation of a plasmachannel, extending longitudinally across the gas density maximum and expandingradially with time. These results are well captured by large-scaleparticle-in-cell simulations, which reveal that the detected fast ions mostlikely originate from reflection off the rapidly expanding channel walls. Thelatter process is predicted to yield ion energies in the MeV range, whichcompare well with the measurements. Finally, direct laser acceleration is shownto be the dominant mechanism behind the observed electron energization.

Laser-driven ion and electron acceleration from near-critical density  gas targets: towards high-repetition rate operation in the 1 PW, sub-100 fs  laser interaction regime