title: Velocity map imaging using an in-vacuum pixel detector.
abstract: The use of a new type in-vacuum pixel detector in velocity map imaging (VMI) is introduced. The Medipix2 and Timepix semiconductor pixel detectors (256 x 256 square pixels, 55 x 55 microm2) are well suited for charged particle detection. They offer high resolution, low noise, and high quantum efficiency. The Medipix2 chip allows double energy discrimination by offering a low and a high energy threshold. The Timepix detector allows to record the incidence time of a particle with a temporal resolution of 10 ns and a dynamic range of 160 micros. Results of the first time application of the Medipix2 detector to VMI are presented, investigating the quantum efficiency as well as the possibility to operate at increased background pressure in the vacuum chamber.
authors.affiliation: FOM-Institute for Atomic and Molecular Physics (AMOLF), Science Park 113, 1098 XG Amsterdam, The Netherlands. g.gademann@amolf.nl
authors.forename: Georg
authors.initials: G
authors.lastname: Gademann
authors.forename: Ymkje
authors.initials: Y
authors.lastname: Huismans
authors.forename: Arjan
authors.initials: A
authors.lastname: Gijsbertsen
authors.forename: Julia
authors.initials: J
authors.lastname: Jungmann
authors.forename: Jan
authors.initials: J
authors.lastname: Visschers
authors.forename: Marc J J
authors.initials: MJ
authors.lastname: Vrakking