DASEL: Dark Sector Experiments at LCLS-II

Understand

This paper describes the concept for the DArk Sector Experiments at LCLS-II (DASEL) facility which provides a near-CW beam of multi-GeV electrons to the SLAC End Station A for experiments in particle physics.

• The low-current multi-GeV electron beam is produced parasitically by the superconducting RF linac for the LCLS-II X-ray Free Electron Laser, which is under construction at SLAC.
• DASEL is designed to host experiments to detect light dark matter such as the Light Dark Matter eXperiment (LDMX) but can be configured to support a wide range of other experiments requiring current ranging from pico-amps to micro-amps.