The PANTER X-ray test facility is located in Neuried on the southwest outskirts of Munich. The aerial photograph shows the 120-m-long vacuum tube (Ø1 m), with the X-ray source system at one end and the main test chamber (12 m long and Ø3.5 m) at the other end. The facility can be extended to a total length of 147 m to measure f = 20 m optics. Globally, it is superseded in size only by the NASA XRCF X-ray test facility in Huntsville, AL, USA.
The PANTER X-ray test facility is used primarily for characterisation of X-ray telescopes. Imaging properties, reflectivity, and scattering can be studied on single shells, as well as on nested mirror systems or complete telescopes. In addition, a huge number of detectors, focal plane instruments, transmission and reflection gratings, and X-ray absorption filters have been tested and developed at PANTER.
PANTER was originally built between 1977 and 1982 to support the development of the ROSAT X-ray telescope. Since then a large number of projects have made use of the facility, including EXOSAT, BeppoSAX, JET-X, ABRIXAS, XMM-Newton, Swift, Suzaku, HXMT-Insight, eROSITA, Einstein Probe, and SVOM. Alongside the optics, the cameras and detectors for these telescopes, as well as filters and gratings (e.g. LETG on Chandra, RGS on XMM-Newton), have been tested and calibrated at PANTER.
The development, testing, and calibration of the optics for future missions, such as eXTP, NewATHENA, and the ground-based Axion Telescope IAXO, as well as many activities supporting X-ray optic technology development, are ongoing at PANTER.
In the context of NewATHENA, considerable effort has been devoted to testing Silicon Pore Optics (SPOs) both at the single-module level and in groups of modules mounted in a representative petal of the mirror assembly. These petal-level tests are used to verify the thermal properties of the mirror assembly. In addition, the optics and X-ray sources for the dedicated NewATHENA X-ray test facilities BEaTriX and Vert-X are being tested and calibrated at PANTER.
PANTER also has a smaller vacuum chamber used for thermal cycling and thermal-vacuum testing of X-ray flight instrumentation. Spacecraft subsystem tests have been carried out in this chamber; it was used intensively for the XMM-Newton and eROSITA projects.
