Berkeley Lab

Laser-Plasma Accelerators for High-Energy Physics

Early steps on the development path toward the dream of an LPA-based collider

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A schematic of a electron-positron collider consisting of many 10 GeV laser-plasma acceleration stages. Click for larger version.

Laser-plasma accelerators (LPAs) can produce ultrahigh fields of 10-100 GV/m, resulting in an accelerating gradient some three orders of magnitude beyond that produced by convention radio-frequency accelerators. Therefore LPAs may provide a technology for more-compact high-energy colliders.

As shown in the schematic, a vision for a LPA-based collider consists of coupling many individual LPA stages together, each LPA stage boosting the particle beam energy by 10 GeV, and each stage driven by laser with a pulse energy on the order of tens of joules, which is similar to the pulse energy of the BELLA laser system. A collider will require a very high repetition rate, on the order of 10 kHz, well beyond the capability of the BELLA laser, which points to the need to develop high repetition rate lasers for high energy physics applications.

A major focus of the BELLA Center is to explore and develop LPAs for high energy physics applications. One primary goal is to demonstrate the production of electron beams at the 10 GeV level using the BELLA laser and a meter-scale plasma. Another goal is to demonstrate the coupling of two LPA stages, each powered by separate laser pulses. The first stage will produce a relativistic electron beam, which is then coupled to the second LPA stage for acceleration to the 1 GeV level.

Magnetic spectrometer data showing the production of high quality electron beam at 1 GeV from a 3 cm plasma structure

Magnetic spectrometer data showing the production of high quality electron beam at 1 GeV from a 3 cm plasma structure

Research also includes the experimental, theoretical, and numerical study of the basic physics of LPAs. These basic physics studies include the propagation of intense laser pulses in plasma channels, large amplitude plasma wave generation, particle self-trapping and injection, as well as many other nonlinear laser-plasma phenomena. To assist in this research, the development and use of large-scale simulations are carried out, such as those based on particle-in-cell codes.