Fil Marc Keita Daniel

We looked at the "broken" channel 5 today, but no problem was found. After reconnecting the ISS chassis and reshuffling some of the cables under HAM2, everything was working fine again.

We took the opportunity to measure dark noise with the PSL shut off. The attached plot shows the dark noise with no light on the photodetectors and calibrated in relative intensity noise for 50 W input. Also, shown is the shot noise for 30 mA of photocurrent at the 3 x 10^–9 level.

There is an AC coupling in the RIN_INNER and RIN_OUTER channels which explains the discrepancies below 0.3 Hz. ADC noise explains the difference between these channels and the RIN_ERR1 and RIN_ERR2 at frequencies of 300 Hz and above.

We are not sure why there is a difference between PDA and PDB. The PDB readout seems to be ADC noise limited through the entire freqyuency band.