Nonintrusive Measurement of Time-Resolved Emittances of 1-GeV Operational Hydrogen Ion Beam Using a Laser Comb...

We proposed and demonstrated a novel technique to measure time-resolved transverse emittances of the hydrogen ion (H−) beam in a 1-GeV high-power accelerator. The measurement is performed in a nonintrusive manner by using a laser comb—laser pulses with controllable multilayer temporal structure. The technique has been applied to the transverse emittance measurement of a 1-GeV H− beam in the Spallation Neutron Source high energy beam transport line. More than 20 time-resolved emittances have been simultaneously determined within a macropulse, a single minipulse, or a single bunch of the 1.4-MW neutron production H− beam from a single measurement.