Muggli, P. JACoW Geneva, Switzerland 978-3-95450-180-9 10.18429/JACoW-NAPAC2016-WEPOA02 English 687-689 WEPOA02 ion laser plasma diagnostics experiment Contribution to a conference proceedings 2017 2017-01 http://dx.doi.org/10.18429/JACoW-NAPAC2016-WEPOA02 https://jacow.org/napac2016/papers/wepoa02.pdf The AWAKE experimental program is scheduled to start at the end of 2016. The aim of the first experiments is to detect and study the self-modulation instability (SMI) of the long proton bunch ~12cm in a plasma with wakefields of period of ~1.2mm. The occurrence of SMI results in the formation of a charge core surrounded by a halo in the time-integrated images of the proton bunch transverse profile. Transverse profiles are obtained from scintillator screens and from optical transition radiation (OTR). The OTR is time resolved using a ps-resolution streak camera to determine the start of the wakefields along the bunch on a slow time scale (~ns), i.e., the location of the seeding of the SMI generated by the ionizing laser pulse. The modulation period is measured using the faster time scale (~ps). Coherent transition radiation (CTR) is analyzed by a heterodyne system to also yield the modulation frequency. Later experiments will sample the wakefields generated by externally injecting low-energy (~15MeV) electrons expected to be accelerated to the GeV energy level over the 10m-long plasma. Progress toward the completion of the experimental set-up will be presented.