the ip adress of the smaract driver is now 10.0.53.10:5000

please think about putting such kind of changes in the logbook

following the measuremetn at 879.9 MHZ of the laser theoptical cavity length has been adjusted to that value from 876MHz setting of the 5th of may 21.

new motor positions:

M3/M4 : -2.9mm

M1/M2 : +5.196mm

A 10V applied on the laser piezo was found to induce a frequecny change of about 5kHz, compatible with expectations from the piezo sensitivity. this was measured by a freqeuncy analysis of the signal produced by the laser itself on a photodiode det10a

doing the sensitivty measurement of the piezo we observed satellite peaks around 800 to 900 Mhz. Removing the phones from the experience room(in the cupboard in the sas) removed that effect immediately.

a cavity length measurement gave 880.9Mhz. The m1/M2 have been put to +5.1000mm both M3/M4 srill at -2.9mm

to find the fundamental mode we moved the cavity mirrors to new positions:

+5.104mm for both planar mirrors in closed loop

spherical unchanged (-2.9mm)

the M1 is not at 5.1045mm to put the fundamental on the scanning range of the laser piezo

M2 still at 5.104mm

M3/M4 at -2.9mm still

after 3hours (1pm --> 4pm) the cavity moved by 12um in total

new positions: +5.1065mm on M1 and M2 (5.1050 before)

the drift is 4um/hour which amounts to about 10kHz drift / hour+the temperature of the optics room also changed unfortunaltey (linked to extinction of air flow at around 11am this morning). the drift in the room temperature was about 0.5K from 1pm to 2pm and 3K since 11am.

maybe this measurement needs to be redone to more precisely correlate the drift to an overall temperature change

M1 and M2 at 5.1085mm and M3 and M4 at -2.9mm