Initial beam-profiling tests with the NML prototype station at the Fermilab A0 Photoinjector

TL;DR

This paper reports initial tests of a beam-profile diagnostics station prototype at Fermilab's A0 Photoinjector, demonstrating its optical resolution and effectiveness for low-power electron beams.

Contribution

The paper introduces a novel beam-profile diagnostics station using radiation converter screens and optical systems for high-resolution beam profiling at Fermilab.

Findings

Achieved better than 20 μm spatial resolution

Successfully tested with electron beams of 15 MeV energy

Demonstrated capability for beam sizes from 45 to 250 microns

Abstract

The beam-profile diagnostics station prototype for the superconducting rf electron linac being constructed at Fermilab at the New Muon Lab has been tested. The station uses intercepting radiation converter screens for the low-power beam mode: either a 100-\mu m thick YAG:Ce single crystal scintillator or a 1-\mu m thin Al optical transition radiation (OTR) foil. The screens are oriented with the surface perpendicular to the beam direction. A downstream mirror with its surface at 45 degrees to the beam direction is used to direct the radiation into the optical transport. The optical system has better than 20 (10) \mu m rms spatial resolution when covering a vertical field of view of 18 (5) mm. The initial tests were performed at the A0 Photoinjector at a beam energy of ~15 MeV and with micropulse charges from 25 to 500 pC for beam sizes of 45 to 250 microns. Example results will be presented.