Enhanced Proton Acceleration by Laser-Driven Collisionless Shock in the Near-Critical Density Target Embedding with Solid Nanolayers

<div>Time evolution of longitudinal electrostatic field for (a) the PT and (b) the NLT, where the black dashed line marks the shock front for the PT and the dotted line for the NLT. The hole-boring mechanism in the early stage is also marked as green dashed line, and the hole-boring velocity <span class="nowrap"><svg height="11.5303pt" id="M58" style="vertical-align:-3.18148pt" version="1.1" viewbox="-0.0498162 -8.34882 63.466 11.5303" width="63.466pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M219 86C216 168 211 250 206 337C201 410 189 448 163 448C131 448 79 396 43 344L60 322C91 359 110 375 118 375S132 358 136 298C141 238 152 81 155 -12H182C242 62 331 177 390 258C435 321 451 360 451 391C450 424 432 448 408 448C390 448 372 435 366 419C362 410 362 401 366 394C373 383 376 367 376 350C376 283 262 138 221 86H219Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,5.811,3.132)"><path d="M870 650H600L593 618C681 609 684 605 669 516L641 367H261L286 516C302 603 313 610 391 618L398 650H132L123 618C214 610 218 606 200 516L127 130C113 46 107 40 25 32L18 0H290L298 32C204 40 200 42 214 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Laser and Particle Beams

fig5

Figure 5

Figure 5: Enhanced Proton Acceleration by Laser-Driven Collisionless Shock in the Near-Critical Density Target Embedding with Solid Nanolayers 