Newly Commissioned iP2 Beamline of the BELLA PW Facility for Investigation of High Intensity Laser-Solid Interactions

The newly commissioned short focal length, high intensity PW laser beamline, named iP2, at the BELLA Center enables frontier experiments in high energy density science. This 1 Hz system provides a focused beam of <3 micron in FWHM, resulting in an on-target peak intensity greater than 5 × 10²¹ W / cm², and a pointing fluctuation on the order of 1 µrad. A temporal contrast ratio of <10^-14 on the nanosecond timescale is expected with the addition of an on-demand double plasma mirror setup in the near future. This beamline is well suited for studies requiring ultra-high intensity and substantial control over the temporal contrast, such as investigation of novel regimes of advanced ion acceleration and their applications. The recent results from iP2 high power commissioning experiments are presented as well as the outlook for in vivo radiobiological studies at ultra-high dose rates. In preparation for an experimental campaign to investigate the magnetic vortex acceleration regime, a series of 3D simulations using the WarpX code were performed to optimize the target design and guide the development of the main diagnostics. We studied the acceleration performance with different laser temporal contrast conditions at normal and oblique laser incidence angles.