Coherent Diffraction Radiation as a Tool for Longitudinal Beam Profile Diagnostics at CTF3

Com­pact Lin­ear Col­lid­er (CLIC) is a mul­ti-TeV elec­tron-positron col­lid­er for par­ti­cle physics based on an in­no­va­tive two-beam ac­cel­er­a­tion scheme. The CLIC Test Fa­cil­i­ty 3 (CTF3, CERN) aims to demon­strate fea­si­bil­i­ty of this con­cept. The mon­i­tor­ing of a lon­gi­tu­di­nal pro­file will be very im­por­tant for the CLIC. The op­ti­miza­tion of the lon­gi­tu­di­nal charge dis­tri­bu­tion in a bunch is cru­cial for the max­imi­sa­tion of the lu­mi­nos­i­ty and also for an op­ti­mal per­for­mance of a CLIC drive beam. A setup for the in­ves­ti­ga­tion of Co­her­ent Diffrac­tion Ra­di­a­tion (CDR) from tar­gets with var­i­ous con­fig­u­ra­tions as a tool for non-in­va­sive lon­gi­tu­di­nal elec­tron beam pro­file di­ag­nos­tics has been de­signed and in­stalled in the CRM line of the CTF3 [1, 2]. In this re­port we pre­sent the sta­tus of the ex­per­i­ment and re­sults on in­ter­fer­o­met­ric mea­sure­ments of CDR from a sin­gle tar­get con­fig­u­ra­tion. Stud­ies on down­stream back­ground con­tri­bu­tion in the CRM line have been per­formed. Re­cent­ly we have up­grad­ed the sys­tem by in­stalling a sec­ond tar­get. In this re­port we shall also demon­strate the re­sults on sim­u­la­tions of CDR spa­tial dis­tri­bu­tion from the two tar­get con­fig­u­ra­tion.