Beam instrumentation at the multi-turn linac passages of MESA

We will present the status of the beam instrumentation at MESA. To put MESA into operation various diagnostic systems are necessary. To optimize the beam the position and phase with respect to the accelerating RF needs to be optimized to be able to recirculate the beam for multi-turn operation or ERL mode respectively. On the other hand, an absolute beam current measurement is necessary. This can be achieved with a DCCT on the linac axis. The instrumentation will be installed very close to our cryo modules and needs to fulfil the excellent vacuum requirements for superconducting RF.