@misc{oai:repo.qst.go.jp:00074813,
 author = {ドーバー, ニコラス ピーター and Nishiuchi, Mamiko and Kevin Koga, James and Sakaki, Hironao and Kondo, Kotaro and Kiriyama, Hiromitsu and Ogura, Koichi and Pirozhkov, Alexander and Sagisaka, Akito and Kando, Masaki and Kondo, Kiminori and Dover, NicholasPeter and Nishiuchi, Mamiko and Kevin Koga, James and Sakaki, Hironao and Kondo, Kotaro and Kiriyama, Hiromitsu and Ogura, Koichi and Pirozhkov, Alexander and Sagisaka, Akito and Kando, Masaki and Kondo, Kiminori},
 month = {Mar},
 note = {State-of-the-art high power laser facilities present numerous potential applications, including the generation of ultra-short and low emittance ion beams.  Understanding the underlying laser-plasma interaction physics and resulting scaling to ultra-high intensities is of great importance for optimising such sources.  We therefore present experimental data of proton acceleration in a sheath field using the ultra-high intensity J-KAREN-P laser (10 J, 40 fs, 5x1021 W/cm2), allowing investigation at the high-intensity frontier.  

We will demonstrate a slower than expected increase in proton energy with decreasing focal spot size, and show that this is due to a reduced sheath lifetime for tight focal spots.  The proton beam spatial profile is found to vary with focal spot size, showing a narrow divergence beam at low energies (<10 MeV).  This, combined with our demonstration of a potentially high repetition rate experimental geometry provides an exciting platform for potential applications at the mid-to-low energy ranges., JPS 74th Butsuri Gakkai 2019},
 title = {Experimental investigation of sheath-driven proton beam parameters in the ultra-short pulse, ultra-high intensity regime},
 year = {2019}
}