Automated Laser Ablation for a Cryogenic Buffer Gas Beam Source

Precision measurements of cold, exotic molecules can provide sensitive tests of the violation of fundamental symmetries and the exploration of physics beyond the Standard Model. Recent studies have shown that radium-containing molecules, such as ²²⁵RaF and ²²⁵RaOH, amplify both parity and time-reversal violating nuclear properties and have a structure favorable for laser cooling. The cryogenic buffer gas beam (CBGB) method offers a generic approach to producing and cooling molecules in the few Kelvin regime as the first step toward laser cooling. In these experiments, the target species are introduced into the buffer gas through laser ablation, where a high-energy pulsed laser is focused onto the solid target to eject gas-phase molecules or atoms. With the aim of improving the efficiency of molecular production, we present the development of an automated laser ablation system for the precise control of the laser beam pointing, triggered rastering, and mapping of the laser position.

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