Laser-Plasma High Energy Physics in Relativistic Self-Trapping of Extreme Light

Based on a presentation at the 48th Vavilov Readings (Lebedev Physical Institute of the Russian Academy of Sciences, April 17, 2024), a review is given of current issues in laser-plasma high energy physics associated with self-trapping of light pulses in relativistic plasma. An analysis is made of electron acceleration in this regime by relativistically intense laser pulses up to sub-GeV energies with multi-nanocoulomb charge carried by the accelerated electron bunch and their possible radiation/nuclear applications. The discussion of the latter includes generation of synchrotron-type secondary radiation from laser-irradiated transparent targets or converter targets in the range from hard X-rays to gamma-rays; generation of terahertz pulses, including unique half-cycle/unipolar pulses; generation of neutrons and positrons; possible deep radiography of strongly shielded objects based on laser-induced ultrabright gamma-ray bursts; an all-optical inverse Compton source for high spatial resolution radiography; and radiation FLASH therapy using laser-accelerated ultrahigh energy electrons.