Locking activity last night :
The free run beat-note in 532 nm has been measured.
However I couldn't close the ALS loop somehow.
Every time I tried closing the loop it broke the Y end PDH lock in a couple of minutes.
(Things to be done)
1. Optimization of the Y end PDH servo loop
1.1 Measurement of the arm fluctuation => to allow re-designing the servo shape
1.2 Preparation of PDH box, and temporary SR560 servo
1.3 Sanity checks on the modulation depth, reflectivity, PD dark noise and etc.,
1.4 Make the servo more robust
1.5 Some modifications on the medm screens
1.6 Activation of the temperature feedback through the realtime digital control
2. Refinement of the broadband RFPD setup
2.1 Investigation of the peak source => there was a relatively big peak around 50 MHz or so.
2.2 Noise characterization of the frequency detection system
2.3 Nicer routing of some cables.
2.4 Make two-more ADC channel connectors
2.5 Power budget on the PSL beat-note setup => estimate the expected RF level of the beat-note
2.6 Realignment of the PSL doubling and resetting of the doubling oven temperature
3. Noise budgeting
3.1 IR locked condition => measure the noise in the green beat-note system.
3.2 ALS engaged condition
3.2.0 shot noise
3.2.1 ADC noise
3.2.2 PD dark noise
3.2.3 freq. discriminator noise
3.3.4 DAC noise through the coil-magnet actuators
3.3.5 End laser suppression
3.3.6 Intensity noise
3.3.7 Thermo-elastic noise
3.3.8 Thermo-refractive noise
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