Reports until 15:07, Tuesday 10 March 2026
H1 SQZ
camilla.compton@LIGO.ORG - posted 15:07, Tuesday 10 March 2026 (89453)
SQZ Notes, Laser back on, tempurature adjusted for coaligned red and green, Can't lock OPO with CLF yet.

Turned laser on first thing and Marc turned on the SQZ High Voltage in the Mech room mezzanine 89449, the PMC and SHG looked without issue. I turned back on the SFI1, SFIO2 and OPO TEC servos (were turned off for venting).

Segment 3 of H1:SQZ-RLF_QPD_A_SEG_3 is broken 89020, so we will need to decide what to do about that but I didn't do anything yet. 

Increased SEED light from 0.5mW to 75mW, then LOCKED_SEED_DITHER, power was then 0.1 mW on SQZT7, previously ~2mW. Checked QPD B, power now 13nW, previously 130nW, for similar CLF_TRIG reflected power. see attached. Can try to realign via QPD_B and ZM2,3 but have not yet done this. 

Changed OPO temp from 31.72 to 33.703 while injecting CLF and scanning the OPO PZT to coalign green and IR peak (Sheila said SEED may have been quicker).

OPO with CLF still didn't lock. With H1:SQZ-OPO_PZT_1_SCAN_TRIGGER_CHANNEL_1_LEVEL and 2_LEVEL reduced from 0.5 to 0.1 and it debatably locked looking at  H1:SQZ-OPO_IR_RESONANCE_CLF_RF but with no signal on H1:SQZ-OPO_IR_PD_DC_POWERMON... maybe the alignment is just very bad.

Pausing here. 

Images attached to this report