Pxie low energy beam transport commissioning

TL;DR

This paper reports on the commissioning of the Low Energy Beam Transport (LEBT) section of the PXIE test accelerator, including phase-space measurements and neutralization schemes validation for the Fermilab PIP-II project.

Contribution

It presents the successful commissioning and characterization of the LEBT system, including phase-space measurements under different neutralization conditions.

Findings

LEBT system was built and commissioned to full specifications.

Phase-space measurements were performed under various neutralization schemes.

Results validate the design and operational parameters of the LEBT.

Abstract

The Proton Improvement Plan II (PIP-II) at Fermilab is a program of upgrades to the injection complex. At its core is the design and construction of a CW-compatible, pulsed H- superconducting RF linac. To validate the concept of the front-end of such machine, a test accelerator (a.k.a. PXIE) is under construction. It includes a 10 mA DC, 30 KeV H- ion source, a 2 m-long Low Energy Beam Transport (LEBT), a 2.1 MeV CW RFQ, followed by a Medium Energy Beam Transport (MEBT) that feeds the first of 2 cryomodules increasing the beam energy to ~25 MeV, and a High Energy Beam Transport section (HEBT) that takes the beam to a dump. The ion source and LEBT, which includes 3 solenoids, several clearing electrodes/collimators and a chopping system, have been built, installed, and commissioned to full specification parameters. This report presents the outcome of our commissioning activities, including phase-space measurements at the end of the beam line under various neutralization schemes obtained by changing the electrodes' biases and chopper parameters.