The VERT-X calibration facility: development and test of the most critical parts

The ground calibration of the New-ATHENA mirror poses significant challenges owing to its unprecedented size, mass, and focal length. VERT-X is innovative calibration facility designed to tackle this exceptionally demanding task. It relies on an X-ray parallel beam, generated by a micro-focus source positioned at the focus of an X-ray collimator. A raster-scan mechanism enables the beam movement, covering all ATHENA optics at varying off-axis angles. The compactness of the concept offers several benefits, including the vertical geometry which implies minimal PSF degradation due to lateral gravity. Furthermore, this allows for a flexible choice of location. Indeed one of the most important feature of VERT-X is its contiguity with the mirror integration facility. The driving factor in the VERT-X design is to meet the ATHENA calibration requirement for Half-Energy Width (HEW) accuracy at 0.1”. Key contributors to the error budget in the VERT-X design include the source size, collimator error, and raster-scan pointing accuracy. This paper provides an overview of the current status of the development of these critical parts and of the first results of their performance test.