Effects of the Shaft Error of an Altazimuth Telescope on Pointing and Tracking Accuracies

It is a new tread to use altazimuth telescopes to increase diameters of modern astronomical telescopes.This paper adopts the spherical geometry to deduce how the shaft error of an altazimuth telescope affects its pointing and tracking accuracies.We describe the detection of the shaft errors of 2m-class telescopes and the processing of such detected data.This paper evaluates the impact of shaft error on pointing and tracking from simulations of pointings and trackings of a target star under the influence of the shaft error.The evaluation can provide theoretical basis for the requirements of the alignment of telescope axis,and provide reference for followed-up corrections of control systems.