title: Single-shot beam-position monitor for x-ray free electron laser.
abstract: We have developed an x-ray beam-position monitor for detecting the radiation properties of an x-ray free electron laser (FEL). It is composed of four PIN photodiodes that detect backscattered x-rays from a semitransparent diamond film placed in the beam path. The signal intensities from the photodiodes are used to compute the beam intensity and position. A proof-of-principle experiment at a synchrotron light source revealed that the error in the beam position is reduced to below 7 μm by using a nanocrystal diamond film prepared by plasma-enhanced chemical vapor deposition. Owing to high dose tolerance and transparency of the diamond film, the monitor is suitable for routine diagnostics of extremely intense x-ray pulses from the FEL.
authors.affiliation: SPring-8∕RIKEN, Sayo-cho, Sayo-gun, Hyogo, Japan.
authors.forename: Kensuke
authors.initials: K
authors.lastname: Tono
authors.forename: Togo
authors.initials: T
authors.lastname: Kudo
authors.forename: Makina
authors.initials: M
authors.lastname: Yabashi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tachibana
authors.forename: Yiping
authors.initials: Y
authors.lastname: Feng
authors.forename: David
authors.initials: D
authors.lastname: Fritz
authors.forename: Jerome
authors.initials: J
authors.lastname: Hastings
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ishikawa