The Linac Laser Notcher For The Fermilab Booster

TL;DR

This paper discusses the development of a laser-based notcher system for the Fermilab linac, aiming to create beam notches at lower energies to reduce activation and improve beam extraction efficiency.

Contribution

It introduces a novel laser notcher concept for linacs, detailing design, implementation, and initial testing for Fermilab's accelerator upgrade.

Findings

Successful initial commissioning of the laser notcher system.

Potential reduction in activation by creating notches at lower energies.

Future plans for system optimization and integration.

Abstract

In synchrotron machines, the beam extraction is accomplished by a combination of septa and kicker magnets which deflect the beam from an accelerator into another. Ideally the kicker field must rise/fall in between the beam bunches. However, in reality, an intentional beam-free time region (aka "notch") is created on the beam pulse to assure that the beam can be extracted with minimal losses. In the case of the Fermilab Booster, the notch is created in the ring near injection energy by the use of fast kickers which deposit the beam in a shielded collimation region within the accelerator tunnel. With increasing beam power it is desirable to create this notch at the lowest possible energy to minimize activation. The Fermilab Proton Improvement Plan (PIP) initiated an R&D project to build a laser system to create the notch within a linac beam pulse at 750 keV. This talk will describe the concept for the laser notcher and discuss our current status, commissioning results, and future plans.