Von Hamos (VH) spectrometers are widely used in several fields, ranging from fundamental physics to very different types of practical applications. However, these type of Bragg spectrometers are usually operated in high rate – high resolution experiments, where the typical source size can be as low as few tens of microns. The VOXES collaboration at the INFN Laboratories of Frascati recently developed a VH spectrometer, making use of Highly Annealed Pyrolitic Graphite (HAPG) mosaic crystals and an X-ray beam optics optimization, which could be used for source sizes up to few mm in the Bragg plane, some tens of mm in the sagittal plane and, if gaseous sources are used, several tens of cm in the X-ray propagation direction. Such kind of spectrometer could be used in a wide range of applications in several fields, going from fundamental physics, synchrotron radiation and X-FEL applications, astronomy, medicine and industry to hadronic physics experiments, measuring exotic atoms with extremely high precision. We present the results obtained with the VOXES spectrometer, in terms of spectral resolution and achievable precision, for a 206.7 mm curvature radius HAPG crystal using Fe K1,2 transition lines.

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