after trying to increase the power and after moving S3 to try to change the size of the beam on the mirrors, the FPC power suddenly droped.

so, we need to remove M1 to check if it has been damaged.

we placed an iris in reflection of the FPC to keep the alignment for the new mirror M1.
the alignment has been done with an iris and the amplifier at 10% (to get a quite round beam) and the beam profiler.
once the iris is almost closed, the alignment is good, using the diffractions rings.