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 parametric study based on 1-D particle-in-cell (PIC) simulationsconducted with the objective of understanding the interaction of intense laserswith near-critical non-uniform density gas targets. Specifically, we aim tofind an optimal set of experimental parameters regarding the interaction of a$\lambda_L$ = 0.8 $\mu$m, $I_L =10^{20}$ W/cm$^2$ ($a_0 = 8.8$), $\tau_L = 30$fs laser pulse with a near-critical non-uniform pure nitrogen gas profileproduced by a non commercial gas nozzle. The PIC code Calder developed at CEAwas used, and both the maximum electron density and the direct lasercontribution to ion acceleration were studied. Shock formation was achieved fora peak electron density $n_e$ ranging between 0.35 $n_c$ and 0.7 $n_c$. In thisdensity interval, the survival of a percentage of the laser pulse until the gasdensity peak, while being strongly absorbed ($>$90$\%$) and creating a hotelectron population in the gas up-ramp, is singled out as a necessary conditionfor shock formation. Moreover, the laser absorption must give rise to a superponderomotive heating of the target electrons in order to launch anelectrostatic shock inside the plasma. The direct laser effect on ionacceleration consists in a strong initial density perturbation that enhancescharge separation while the electron pressure gradients are identified asfundamental for shock formation. The production of a controlled and repetitivegas profile as well as the possibility of performing measurements withstatistical meaning are highlighted as fundamental for conducting a thoroughexperimental study.

Parametric study on ion acceleration from the interaction of ultra-high intensity laser pulses with near-critical density gas targets