A Low Energy H- Beamline for the ALPHA Antihydrogen Experiment

Abstract The CERN ALPHA experiment makes precision measurements of antihydrogen atoms, confined in a superconducting magnetic minimum trap. Recent measurements of the antihydrogen spectrum have already provided high-resolution tests of fundamental symmetries, and ALPHA has now embarked on an ambitious upgrade programme aimed at directly comparing hydrogen and antihydrogen within their existing atom trap. One aspect of this upgrade will be the development of a low-energy (50 eV) hydrogen ion source that is compatible with ALPHA’s existing magnetic charged particle beamlines. PELLIS, previously developed at JYFL, is a 5 keV filament-driven source that generates H- beams with low emittances an…