A transparent two-dimensional in situ beamposition and profile monitor for synchrotron X-ray beamlines

摘要

A compact, inexpensive and easy- to- construct two- dimensional in situ beam-position and profile monitor for synchrotron X- ray beamlines is presented. The device is based on the collection of spatially resolved scattered radiation from a polyimide foil. The X- ray beam passes through a foil placed in the path of the beam, which absorbs no more than 3% of the beam at 12 keV. The scattered radiation is collected at an angle of 90 degrees through a collimator located below the foil onto a CCD sensor. The device was tested on bending- magnet beamline BM26 at the ESRF synchrotron radiation source and has a positional sensitivity better than 10 mu m with a large working range of 25 mm x 25 mm. Although the device is optimized for use in the range 10 - 12 keV, it can easily be modified for use with higher- energy beams by using a suitably chosen scattering foil.