title: In situ micro-focused X-ray beam characterization with a lensless camera using a hybrid pixel detector.
abstract: Results of studies on micro-focused X-ray beam diagnostics using an X-ray beam imaging (XBI) instrument based on the idea of recording radiation scattered from a thin foil of a low-Z material with a lensless camera are reported. The XBI instrument captures magnified images of the scattering region within the foil as illuminated by the incident beam. These images contain information about beam size, beam position and beam intensity that is extracted during dedicated signal processing steps. In this work the use of the device with beams for which the beam size is significantly smaller than that of a single detector pixel is explored. The performance of the XBI device equipped with a state-of-the-art hybrid pixel X-ray imaging sensor is analysed. Compared with traditional methods such as slit edge or wire scanners, the XBI micro-focused beam characterization is significantly faster and does not interfere with on-going experiments. The challenges associated with measuring micrometre-sized beams are described and ways of optimizing the resolution of beam position and size measurements of the XBI instrument are discussed.
authors.affiliation: School of Electrical and Electronic Engineering, The University of Manchester, Sackville Street Building, Manchester M13 9PL, UK.
authors.forename: Anton
authors.initials: A
authors.lastname: Kachatkou
authors.affiliation: Detector Group, Diamond Light Source Ltd, Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK.
authors.forename: Julien
authors.initials: J
authors.lastname: Marchal
authors.affiliation: School of Electrical and Electronic Engineering, The University of Manchester, Sackville Street Building, Manchester M13 9PL, UK.
authors.forename: Roelof
authors.initials: R
authors.lastname: van Silfhout
keywords: X-ray imaging; beam diagnostics; beam size measurements; micro-focus; pinhole camera; scattering measurements