Sep 24 – 30, 2017
La Biodola, Isola d'Elba
Europe/Rome timezone

First results of CTR measurement of modulated proton bunch in AWAKE

Sep 27, 2017, 4:18 PM
SML, Sala Maria Luisa, HH

SML, Sala Maria Luisa, HH

talk WG1 - Electron Beams from Plasmas WG1_Parallel


Dr Mikhail Martyanov (Max Planck Institut fur Physik, Munich)


We present a first measurements of microwave coherent transition radiation (CTR) emitted by a SPS proton bunch in AWAKE experiment at CERN. Detailed simulation predicts a significant and experimentally detectable amount of CTR power. Strong signal has been detected in all non-frequency-resolved detectors when proton bunch interacted with a Rubidium plasma. We used three Schottky diodes integrated into different wave-guides designed to measure a signal in 90-140, 140-220, 220-320 GHz bands. Preliminary results show a presence of harmonics of plasma frequency in CTR signals as is predicted by our CTR simulations. Also we used a quasi-optical Schottky diode, placed behind a set of 7 cut-off wave-guides mounted onto a remotely controlled wheel. This setup was used to find (roughly) a CTR carrier frequency in between of two cut-offs. We attempted a novel heterodyne detection of a CTR microwave burst based on specially designed photo-sensitive Schottky diode that mixes a microwave CTR signal with the intensity beat of two tunable CW lasers as a local frequency input, aiming at measuring the bunch modulation frequency that is expected to be equal to the plasma electron frequency.

Primary author

Dr Mikhail Martyanov (Max Planck Institut fur Physik, Munich)


Prof. Allen Caldwell (Max Planck Institute for Physics) Mr Falk Braunmueller (Max-Planck Institute for Physics) Prof. Patric Muggli (Max-Planck-Institut für Physik)

Presentation materials