title: Benchmarking of electro-optic monitors for femtosecond electron bunches.
abstract: The longitudinal profiles of ultrashort relativistic electron bunches at the soft x-ray free-electron laser FLASH have been investigated using two single-shot detection schemes: an electro-optic (EO) detector measuring the Coulomb field of the bunch and a radio-frequency structure transforming the charge distribution into a transverse streak. A comparison permits an absolute calibration of the EO technique. EO signals as short as 60 fs (rms) have been observed, which is a new record in the EO detection of single electron bunches and close to the limit given by the EO material properties.
authors.affiliation: FOM Institute for Plasma Physics Rijnhuizen, Edisonbaan 14, 3439 MN Nieuwegein, The Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Berden
authors.forename: W A
authors.initials: WA
authors.lastname: Gillespie
authors.forename: S P
authors.initials: SP
authors.lastname: Jamison
authors.forename: E-A
authors.initials: EA
authors.lastname: Knabbe
authors.forename: A M
authors.initials: AM
authors.lastname: MacLeod
authors.forename: A F G
authors.initials: AF
authors.lastname: van der Meer
authors.forename: P J
authors.initials: PJ
authors.lastname: Phillips
authors.forename: H
authors.initials: H
authors.lastname: Schlarb
authors.forename: B
authors.initials: B
authors.lastname: Schmidt
authors.forename: P
authors.initials: P
authors.lastname: Schmüser
authors.forename: B
authors.initials: B
authors.lastname: Steffen