Workers: Akutsu-san, Simon

We tried to get a procedure of measuring the yaw-alignment of the WAB inside the cryostat. For that purpose, we did:

• Bringing a laser-leveler and a tripod inside the cryostat; it is necessary to get the leveler to a certain height where we can see the laser-light on top of the baffle and on the optical table at the same time!
• We were looking for a good spot for the tripod, but unfortunately even the most lowest position was still too high for getting a light to the main-beam indication-mark on the optical table (see pictures 1-3)
• Then we tried to build an improvised tower of some solid bodies to the most appropriate height and took pictures (4-5)
• To our impression, it seems that the baffle has a yaw-alignment within the allowable error (which is one degree)
• However, for a more sophisticated stand within the cryostat, we would need a more lower tripod (40 cm + 10 cm variance, or so; the tower itself is 45 cm in height measured from the cryostat ground). That would be needed for the actual WAB!