[Max and Kiwamu]

A few days ago, we found that there was almost no light coming out from the ALS-PSL fiber [1]. This was thought to be a misalignment in the launcher setup on the PSL table.

Today we entered the PSL room and realigned the setup. Although we screwed up the previous alignment at the beginning due to the lack of a right measurement device, at the end we became able to couple 40% of the incident light (Pin ~ 4.6 mW) into the fiber. Note that the best coupling efficiency in the past was 60% and therefore we maybe able to squeeze some more power from it, but we are satisfied with this number at the moment.

[1] LHO alog 4721 "PSL reference cavity transmission picked-off and launched into ALS fiber"