Oli, Camilla WP12203. Repeat of some of the work done in 2019: EX: 52608, EY: 52636, older: part 1, part 2, part 3.
We misaligned ITMY and turned off the ALS-Y QPD servo with H1:ALS-Y_PZT_SWITCH and placed the Ophir Si scanning slit beam profiler to measure both the 532nm ALSY outgoing beam and the ALSY return beam in the HWS path.
The outgoing beam was a little oblong in the measurements but looked pretty clean and round by eye, the return beam did not! Photos of outgoing and return beam attached. Outgoing beam was 30mW, return beam 0.75mW.
Attached is the 13.5% and D4sigma measurements, I also have photos of the 50% measurements if needed. Distances are measured from the optic where HWS and ALS beams combine, ALS-M11 in D1400241.
We had previously removed HWS-M1B and HWS-M1C and translated HWS-M1A from whats shown in D1400241-v8 to remove clipping.
TJ, Camilla
We expanded on these measurements today and measured the positions of the lenses and mirrors in both ALS and HWS beampaths and took beamscan data further from the periscope, where the beam is changing size more. Data attached for today and all data together calculated from the VP. Photo of the beamscanner in the HWS return ALS beam path also attached.
Oli, Camilla
Today we took some beam measurements between ALS-L6 and ALS-M9. These are in the attached documents with today's data and all the data. The horizontal A1 measurements seemed strange before L6. We're unsure why as further downstream when the beam is larger and easier to see by eye it looks round.
