Results from a Prototype Chicane-Based Energy Spectrometer for a Linear Collider

TL;DR

This paper reports on a prototype chicane-based energy spectrometer tested at SLAC, achieving a single bunch energy resolution of 5e-4, suitable for high-precision measurements at future linear colliders.

Contribution

It presents the design, implementation, and operational experience of a prototype energy spectrometer using a 4-magnet chicane for high-energy linear colliders.

Findings

Achieved a single bunch energy resolution of 5e-4.

Demonstrated operational stability and measurement capability.

Suggested improvements for future spectrometer designs.

Abstract

The International Linear Collider and other proposed high energy e+ e- machines aim to measure with unprecedented precision Standard Model quantities and new, not yet discovered phenomena. One of the main requirements for achieving this goal is a measurement of the incident beam energy with an uncertainty close to 1e-4. This article presents the analysis of data from a prototype energy spectrometer commissioned in 2006--2007 in SLAC's End Station A beamline. The prototype was a 4-magnet chicane equipped with beam position monitors measuring small changes of the beam orbit through the chicane at different beam energies. A single bunch energy resolution close to 5e-4 was measured, which is satisfactory for most scenarios. We also report on the operational experience with the chicane-based spectrometer and suggest ways of improving its performance.