In a full-scale particle accelerator, electrons fly along a kilometers-long path as microwaves bombard them, boosting the particles to near light speed. Such a high-energy electron beam, produced at facilities such as California’s SLAC National Accelerator Laboratory, enables a variety of experiments, including capturing extremely detailed images and probing the structures of molecules. But particle accelerators are expensive, require scientists to travel from locations all over the world and cannot accommodate all the researchers who submit requests to book time.