Bias Alignment of the VERITAS Telescopes

Abstract

The mirror facets on the VERITAS telescopes, which are of Davies-Cotton design, are aligned in the horizontal stow position using a laser projector at their radius of curvature. The instrument used will be described. The optical support structure is subject to some gravitational slumping with elevation which can be counteracted by bias alignment (deliberate misalignment at 0° elevation). In practice this allows the optimum point spread function (PSF) to be attained over an elevation range from 50° to 85°.

Publication
In Proceedings of the 30th International Cosmic Ray Conference
John Kildea
John Kildea
Associate Professor (tenured) of Medical Physics