Jim, Ryan C, TJ

The picket fence station NEW had a large transient that put us into earthquake mode during observing. The code did not register this transient as a glich at first which caused the SEI_ENV mode transition. Looking to the picket fence code it looks like we might be able to tune the glitch settings a bit, but we would have to try out some values over a period of time. It might be worth checking with picket fence experts before we play with this code too much.

This isn't the first time we've seen this, but perhaps the first time we've aloged it. After the 10minute cool down period SEI_ENV returned back to a CALM mode.

I ran a bruco starting at 1398626829 for 2580 seconds to see what channels are coherent with DARM after our adjustment of the output mode cleaner angular control loop offsets were changed.

It can be found here.

Elenna's instructions for running them are here.

1398629440

This lock loss had that the weird ETMX wiggle just before the lock loss that we've seen in past lock losses.

Back to Observing at 1926 UTC after a planned comissioning period. We were unable to get calibration measurements since the IFO lost lock just before planned commissioning  and during commissioning.

Jennie W, Gabriele

I tested the offsets calculated by Gabriele's code that we used to analyse line dithers in the OMC ASC loops here.

We tested them during the commissioning period and put the following offsets into OMC-ASC_QPD_{A,B}_{PIT,YAW}_OFFSET. Since the offsets here were turned off by default I zerod them and then stepped them up slowly so we didn't saturate the OMC ASC loops.

See the attached ndscope showing kappa c improve after we finished putting these offsets in.

We lost lock about 15 minutes after I finished ramping these in due to unrelated issues.

Sheila suggested we put the all the offsets for the QPDs in one place. Since we already had offsets in the filter blocks: H1:ASC-OMC_{A,B}_{PIT,YAW}_OFFSET, I added the offsets for Gabriele's code in these filter banks instead.

I accepted these in safe.snap and OBSERVE.snap as well as the zero values for the OMC-ASC_QPD_{A,B}_{PIT,YAW}_OFFSETs.

offset = exisiting + offset from Gabriele's code

A_PIT = -0.25 - 0.12

A_YAW = 0.1 + 0.15

B_PIT = -0.05 - 0.12

B_YAW = 0.07 - 0.18

We will re-evaluate once we are thermalised.

I ran the A2L script descirbed here at the start of commissoning time this morning, and immediately after manually tuned P2L coefficents for the ETMs.  I was able to improve the CHARD P to DARM coupling by about 25dB compared to the script's result. I tried tuning the ITM coefficents, but there wasn't much room to improve them. 

I've updated the guardian values for ETMX, ETMY and ITMX (for a very small improvement on ITMX). 

Compared to the script, my adjustments were fairly coarse.  The script adjusted ETMX P2L from 3.1715 to 3.0875, while I then adjusted it to 3.35.  For ETMY the script adjusted it from 4.682 to 4.7747, I adjusted it to 4.5.  This resutls in the improvement shown in the attachment. 

Editing to add: we relocked with these new P2L values, and the CHARD P to DARM coupling is still fairly low early in the lock (3rd attachment).  The A2L coefficents aren't very sensitive to thermalization, which is good news.

J. Kissel, A. Effler

Executive Summary:

The calibration for all QTOP (D1001782) and TTOP (D1001242) coil driver's FASTIMON channels that are using the frequency-independent "current monitor" circuit of the broadband coil driver monitor circuit (D0902747) is 
    QTOP = 0.0114 [mA/ct] and 
    TTOP = 0.0153 [mA/ct],
respectively with the "[mA]" being current across the coil, and "[ct]" being "straight off the ADC" counts.

Derivation

From the math outlined in the "Other Files" of the older, "broadband" coil driver monitor circuit, D070480 and stitching together how various voltage signals passed around from page to page of the drawings, one can compute the calibration of the FASTIMON channels for a given coil driver as 

    FASTIMON ADC [ct] = voltage measured across two legs worth of output impedance in the coil driver board drawing
                        * ( [differential legs' voltage to single-ended output voltage converter node in the monitor board drawing]
                             * "single-ended voltage piped into only one leg of differential ADC" factor of two its DB25 output J1 in the interconnect drawing
                             * general standards 16-bit differential ADC calibration)
where
           calibration = (the stuff in parentheses)

         ADC [ct]        [                         "R1" [V_SE] ]    2 [V_DF]    2^16 [ct]      
    ----------------   = [ 2 * Z_OUT [V_DF / A] *  ----------- ] *  -------- * ----------- 
    Coil Current [A]     [                         "R2" [V_DF] ]    1 [V_SE]    40 [V_DF]     

where "R1" = R25, R35 = 10e3 [V/A], and "R2" = R24, R27, R29, R33 = 30e3 [V/A].


So, for the QUAD / Triple TOP coil driver (see circuit diagram D0902747 of chassis assemblies QTOP = D1001782 and TTOP = D1001242), that's, the output impedance of one leg is
    Z_OUT   = (R5+R1) || (R90+R91) 
            = (R5+R1) * (R90+R91) / (R5+R1 + R90+R91)

    Z_OUT^(QTOP) = (44 * 440) / (44 + 440) = 40.00 [V/A]
    Z_OUT^(TTOP) = (32 * 440) / (32 + 440) = 29.83 [V/A]
which makes the calibration

calibration_QTOP [ct/A] = 2 * 40.00 [V/A] * (10e3 / 30e3) * 2 * (2^16 / 40 [ct/V])
                        = 8.7381e+04 [ct/A]
      or 87.381 [ct/mA]
      or 0.0114 [mA/ct]

calibration_TTOP [ct/A] = 2 * 29.83 [V/A] * (10e3 / 30e3) * 2 * (2^16 / 40 [ct/V])
                        = 6.5165e+04 [ct/A]
      or 65.165 [ct/mA]
      or 0.0153 [mA/ct]

Q.E.D.

Gabeiele, Sheila, Camilla

• 16:20UTC: turned off LSC FF and L2L3LP filter in ETMY L2 DRIVEALIGN L2L
• 16:35 - 16:39UTC: ETMY L2 Excitation (FF off)
  • Needed the FF off so that we could turn the L2L3LP filter off.
• 16:40: turned on L2L3LP filter in ETMY L2 DRIVEALIGN L2L and LSC FF
• 16:51 to 16:55UTC: ETMX L2 Excitation (FF on)

FAMIS Link:  25989

Only CPS which looks higher at high frequencies (see attached) would be:

1. ITMx St1 V1 & V2
2. ITMy St1 V2

Wed May 01 10:13:10 2024 INFO: Fill completed in 13min 6secs

Gerardo confirmed a good fill curbside.

https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi?event=1398618745

PRM and SR3 saturations before the lockloss, 2.5 hours into the lock so we still haven't been able to take a thermalized calibration measurement. The only invasive/potential LL causing work going on was some PEM tests by Robert.

TITLE: 05/01 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 5min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.13 μm/s
QUICK SUMMARY: Just got back into Observing after a lock loss, fully auto relock. Planned commissioning today from 9-12 PT

TITLE: 05/01 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: We are Observing and have been Locked for 1.5 hours. Overall quiet night with two almost fully automated relocks. Reminder that LVEA is still Laser Hazard
LOG:

LVEA is still in LASER HAZARD

22:49 Detector Locked for 52 mins and just got into Observing
22:50 Lockloss after 1m 14s Observing

22:56 Lockloss at LOCKING_ALS
23:08 Lockloss from TRANSITION_DRMI_TO_3F
23:49 NOMINAL_LOW_NOISE
23:52 Observing

03:35 Superevent S240501an

04:34 Lockloss
04:49 Lockloss from TURN_ON_BS_STAGE2
05:38 NOMINAL_LOW_NOISE
05:40 Observing                                                                                                                                                          

Lockloss 05/01 04:34UTC

In  77236, Gabriele found the ETMY L2 DRIVEALIGN L2L filter bank has a "L2L3LP" engaged that might be making it harder for us to fit the LSC FF. Today we re-measured the LSC FF, not interatively, with both FF's off and the "L2L3LP" filter off.

Nothing changed but we hope to refit the feedforward and implement them later. When installed, we would need to turn "L2L3LP" filter off after the ISC_LOCK states have been transitioned back to ETMX (77240).

1. ISC_LOCK to NLN_CAL_MEAS
2. Turned off both MICH and SRCL FF.
3. Measured MICH_excitation.xml and SRCL_excitation.xml (used half the nominal exc amplitudes as the FF's were off, saved with full exc amp)
4. Turned off ETMY L2_L2L_DRIVEALIGN L2L3LP filter, see 77236
5. Set up for FF injections, see readme. (turn off F filter and input, but turn on filter to allow excitation though)
6. Measure NoLP_MICHFF_excitation_ETMYpum.xml and NoLP_SRCLFF_excitation_ETMYpum.xml (have adjusted exc shape for L2L3LP being off, used half nominal amplitude)
7. Undo set-up for FF injections, see readme. Keep FF's off as L2L3LP filter's still off.
8. Turn on L2 L2L3LP filter
9. Turn on both MICH and SRCL FF.
10. ISC_LOCK to NLN

All code saved to /opt/rtcds/userapps/release/lsc/h1/scripts/feedforward/