Commissioning and Operation of FAST Electron Linac at Fermilab

TL;DR

This paper details the commissioning and initial operation of Fermilab's 1.3 GHz superconducting RF electron linac, achieving 300 MeV energy and conducting various beam studies during its early runs.

Contribution

It presents the first operational results of the FAST electron linac, including beam energy achievement, machine tuning, and experimental studies during initial commissioning.

Findings

Achieved 300 MeV beam energy with record 250 MeV gain.

Successfully tuned photoinjector for 200 pC bunches at 3 MHz.

Conducted parasitic experiments on wake-fields and beam phase space manipulation.

Abstract

We report results of the beam commissioning and first operation of the 1.3 GHz superconducting RF electron linear accelerator at Fermilab Accelerator Science and Technology (FAST) facility. Construction of the linac was completed and the machine was commissioned with beam in 2017. The maximum total beam energy of about 300 MeV was achieved with the record energy gain of 250 MeV in the ILC-type SRF cryomodule. The photoinjector was tuned to produce trains of 200 pC bunches with a frequency of 3 MHz at a repetition rate of 1 Hz. This report describes the aspects of machine commissioning such as tuning of the SRF cryomodule and beam optics optimization. We also present highlights of an experimental program carried out parasitically during the two-month run, including studies of wake-fields, and advanced beam phase space manipulation.