Plots of this week's (07/26/2023) SUS charge measurement attached.
You can see from the in-lock charge plots that V_eff changed the direction of it's trend at certain times, roughly listed below. In the plot attached, the bias voltage applied to the DC ESD changed at certain times 68123 67698. I wanted too see if these times agreed (shown in G1600699). More investigation is needed as the current plots only go back as far as March but this could explain the trend in ITMY V_eff. Not shown in plot is that EX bias was off 10 March to 05 April 2023 (68446).
Optic |
V_eff changed direction, plots above. estimated dates |
Bias voltage applied to the DC ESD changed, plot attached |
ITMX | Feb/March 2023 | No change |
ITMY | April 2023 | 23rd April 2023 |
ETMX | No change | 28th Feb 2023 |
ETMY | end of April 2023 | 28th Feb 2023 |