PIP-II LLRF Master Oscillator and Precision Reference Line - Station Level Design and Testing

Mosher, Alexander [U. Illinois, Chicago]; Syed, Ahmed [Fermilab]

doi:10.2172/3674489

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PIP-II LLRF Master Oscillator and Precision Reference Line - Station Level Design and Testing

Mosher, Alexander [U. Illinois, Chicago]·Syed, Ahmed [Fermilab]

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Abstract

The PIP-II superconducting linac at Fermilab requires a highly stable RF Reference Line to maintain phase syn- chronization throughout the accelerator. Temperature- induced changes in the electrical length of long coaxial cables can introduce phase drift and measurement errors. The reference-line architecture mitigates these effects by phase averaging the forward and reflected RF signals, while a phase-locked loop anchors the system to the mas- ter oscillator. This work focuses on the characterization, validation, and mechanical integration of station-level RF assemblies using CAD modeling, vector network analyzer measurements, and spectrum analyzer testing. PID-controlled thermal plates will stabilize critical RF components and further reduce temperature-dependent phase and amplitude variations. These methods sup- port repeatable, standardized designs that can be reliably integrated across the different reference-line stations.

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Mosher, Alexander [U. Illinois, Chicago], Syed, Ahmed [Fermilab]. 2026-09-03. PIP-II LLRF Master Oscillator and Precision Reference Line - Station Level Design and Testing. https://doi.org/10.2172/3674489

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