I've quantified the changes that will take place in the GDS calibration correction filters when the ER8/O1 update occurs. A summary of the changes are:

• Actuation time delay update causes about 6 degrees of change in the phase accross 1 kHz
• Updates to the analog AA/AI filters cause < 5% change amplitude across all freqeuncies and about 7 degrees of change in phase across 8kHz
• Removal of ESD low-noise-low-voltage driver pole correction removes < 0.1% change in amplitude, mostly at high frequencies and about 2.5 degrees in phase across 1kHz
• Uncompensated OMC whitening poles update causes ~25% change in amplitude across 8kHz and ~60 degree change in phase across 8kHz.

In total: 

• The residual correction filter updates cause 16% change in amplitude and 50 degree change in phase across 8 kHz.
• The control correction filter updates cause <1% change in amplitude and 2.5 degree change in phase across 1 kHz 

The attached plots illustrate the changes described above.

Background: As a follow-up to Josh et al.'s finding that an EX air compressor is likely seismically injecting noise into DARM (alog 21436), a similar study was done for EY. 

Summary:

• it's likely an air compressor at EY is injecting seismic ground motion noise that couples to the optics table motion
• there is currently no evidence this couples to DARM

Details: 

The counterpart channel used in 21436 (HVE-EY:INSTAIR_PT499) was used in the same fashion to gauge whether the local air compressor was turning on. 

The induced motion is much different than observed at EX; it is not transient (on the scale of a second) but about three minutes long, as seen in H1_EY_AirCompressor_Glitch_Example.

This motion was first noticed at 29 and 58 Hz (as shown in this example spectrum, where blue is during an event and red is quiet time 5 minutes prior) there also appear to be shifted/additional harmonics in every other glitch instance, as seen in the plots in LHO_EY_AirCompressor.pdf. 

The attached pdf also demonstrates the correlation between the air compressor turning on (as defined in alog 21436) and 29, 58 Hz motion measured in both the ground and optics table. There is also a correlation with the mainsmon voltage monitor, as was observed for the air-compressor-induced motion seen in EX.

Both the daily hveto results and spectrograms of h(t) show no evidence this is producing transients in h(t), unlike the EX mechanism. 

I did a diag reset on a timing glitch that occurred at around 20:48UTC. THe reset was effected at ~23:28UTC

TITLE: 09/17 [DAY Shift]: 15:00-23:00 UTC (08:00-16:00 PDT), all times posted in UTC
STATE Of H1: Observing, ~70Mpc
SHIFT SUMMARY: Quiet shift. Remained locked entire time. Only out of observing for ~12 minutes (see previous alog).
INCOMING OPERATOR: Ed
ACTIVITY LOG:

(Previous activities in mid shift summary)
20:25 UTC Filiberto taking yellow cart to LSB to pick up package
21:20 UTC Kyle and Gerardo going to Y mid to replace ion pump. Only ended up staging equipment.
22:24 UTC Kyle and Gerardo done.

TITLE: Sep 17 EVE Shift 23:00-07:00UTC (16:00-00:00 PDT), all times posted in UTC

STATE Of H1: Observing

OUTGOING OPERATOR: Patrick

QUICK SUMMARY:Full control room. IFO is locked and in Observing mode for the last 9+ hours @ 70Mpc. Wind is blowing ≤ 10mph. Seismic activity nominally quiet. Lights appear to be off in the LVEA, Mids, Ends and PSL.

Staging ladders, pumps etc. for GV10 AIP replacement (tomorrow) 

Drove past CS on Y-arm side @ 1415, 1435, 1455, 1515 hrs. local

Shift Summary:
Total duty cycle were 47%, 36% and 16% for three days respectively.
Mostly locks were broken due to earthquakes/ increased ground motion or saturation of different parts (like ITMX, PRM etc)
Other than some non-stationarity at low frequency, spectrogram looked clean. Most of the high SNR glitches were noticed below 300Hz
In general high SNR glitch rate was low, but increased due to seismic activity and ETMY saturation
60Hz magnetic periodic glitches are still present with SNR <15, 50Hz glitches are noticed ( alog)
Still loud glitches due to ETMY saturation are the main problem for LHO
Most of the loud events are vetoed out successfully by Hveto
Glitches caused by earthquake showed up as a very loud event (with new SNR 8.5) in BBH search on 7th September. 


Some follow up studies of the Loud glitches: It is suspected that the load glitches might be caused by the ETMY saturation or may be because of some other reason. I scanned few randomly chosen loud glitches.
 Few omega scans can be found here:
https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1124466556.481/
https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1124467378.953/
https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1125200626.78/
https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1125622097.394/

I did see the glitches in ASC_Y_TR_{A/B} channels. But not always before DARM glitches. I am mentioning these particular channels as during ER7 dust glitches were observed in these channels too.

But I have scanned all the times given in the alog by Stefan  and could not find the same pattern. 

https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1126294545/
https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1126434798/
https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1126437892/
https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1126441165/
https://ldas-jobs.ligo-wa.caltech.edu/~nairwita/wdq/H1_1126442379/

I also ran the modified Lockloss tool with the help of Nutsinee using default channel list and did not find any significant channel (other than SUS-ETMY_L3_MASTER_OUT) except the glitch happened at 1126437892. I have attached the lock loss plot for this particular loud glitch and the significant channels came out as the result of modified lockloss script are as given below (the numbers in the second column show the seconds after those channels had loud glitches):

H1:ASC-OMC_B_YAW_OUT_DQ	        0.000	
H1:ASC-OMC_B_SUM_OUT_DQ	        0.000	
H1:ASC-OMC_B_PIT_OUT_DQ	        0.000	
H1:ASC-OMC_A_YAW_OUT_DQ	        0.000	
H1:ASC-OMC_A_SUM_OUT_DQ	        0.000	
H1:SUS-ETMY_L3_MASTER_OUT_LR_DQ	0.001	
H1:SUS-ETMY_L3_MASTER_OUT_LL_DQ	0.001	
H1:SUS-ETMY_L3_MASTER_OUT_UL_DQ	0.001	
H1:ASC-OMC_A_PIT_OUT_DQ	        0.001	
H1:ASC-AS_B_RF36_Q_YAW_OUT_DQ	0.001	
H1:ASC-AS_A_DC_PIT_OUT_DQ	0.001	
H1:SUS-ETMY_L3_MASTER_OUT_UR_DQ	0.001	
H1:ASC-AS_A_DC_SUM_OUT_DQ	0.001	
H1:ASC-AS_A_RF45_Q_YAW_OUT_DQ	0.001	
H1:ASC-AS_A_RF45_Q_PIT_OUT_DQ	0.001	
H1:ASC-AS_A_RF45_I_PIT_OUT_DQ	0.001	
H1:ASC-AS_A_RF36_Q_PIT_OUT_DQ	0.001	
H1:ASC-AS_B_RF36_I_YAW_OUT_DQ	0.001	
H1:ASC-AS_B_DC_SUM_OUT_DQ	0.001	
H1:ASC-AS_A_RF45_I_YAW_OUT_DQ	0.001	
H1:ASC-AS_A_RF36_I_YAW_OUT_DQ	0.001	
H1:SUS-ITMY_L3_LOCK_P_OUT_DQ	0.004	
H1:SUS-ITMY_L3_LOCK_P_IN1_DQ	0.004	
H1:SUS-ITMY_L2_LOCK_P_OUT_DQ	0.004	
H1:SUS-ITMY_L2_LOCK_P_IN1_DQ	0.004	
H1:SUS-ITMX_L3_LOCK_P_IN1_DQ	0.004	
H1:SUS-ITMX_L3_LOCK_P_OUT_DQ	0.004	
H1:SUS-ITMX_L2_LOCK_P_OUT_DQ	0.004	
H1:SUS-ITMX_L2_LOCK_P_IN1_DQ	0.004	
H1:SUS-ITMY_L1_LOCK_P_IN1_DQ	0.007	
H1:SUS-ITMY_L1_LOCK_P_OUT_DQ	0.007	
H1:SUS-ITMX_L1_LOCK_P_OUT_DQ	0.007	
H1:SUS-ITMX_L1_LOCK_P_IN1_DQ	0.007	
H1:ASC-DHARD_P_OUT_DQ	        0.009	
H1:SUS-ITMY_M0_LOCK_P_IN1_DQ	0.011	
H1:SUS-ITMX_M0_LOCK_P_IN1_DQ	0.011	
H1:ASC-DHARD_Y_OUT_DQ           0.140

For all those five times (given in alog 21522) SUS-ETMY_L3_MASTER_OUT had glitches 0.001s after DARM had the loud glitch.(-0.001s before as written in the plot title- Thanks to Hang for noticing this).

In conclusion, it is still not clear to me if ETMY saturation is the reason behind these loud glitches or not.

J. Kissel, D. Tuyenbayev, J. Betzwieser, S. Kandhasamy

We recently found out LHO has not included the LSC Output matrix in their matlab model of the DARM loop (see LHO aLOG 21601), and this resulted in a discrepant phase in the calculation of the time-dependent parameters. Independently, of the few hardware injections we've managed to test thus far, there remains a minus sign found in the H1 reconstruction (LHO aLOG 21616). Finally, Maddie has found that the sign of DELTAL_CTRL is different between the two observatories (no aLOG yet).

The messages: 
- We have found that CAL-CS *also* does *not* include this LSC OUTPUT MATRIX -1. We think this is an error, yet somehow the CAL_DELTAL_EXTERNAL is still showing sensible results, and we don't understand why.

- We believe this explains the missing sign in the inverse actuation filter. LHO has been inverting the DARM matlab model's version of the actuation function, which did *not* include the LSC output matrix, i.e. a -1, and hardware injections are injected upstream of this output matrix in the DARM path.

- We don't understand what we see when the CAL-CS installations comparing between sites (LHO does NOT account the output matrix, where LLO does, and both sites produce sensible DELTAL EXTERNAL ASDs).

Attached are screenshots of the CAL-CS MEDM screen, the replica of the LSC output matrix, and its actual counterpart in from the LSC overview screen, to prove to myself what is true. 

The path forward: 
- A sanity check: Take two transfer functions, DELTAL_CTRL to DELTAL_EXT and DELTA_RESIDUAL to DELTAL_EXTERNAL. Export them into matlab, add them and subtract them. Check if DELTAL_EXTERNAL would even notice if A was + or -. Our intuition says "yes, it should make some nasty bump or zero in the calibrated ASD."
- Make a sign table like LLO has in LHO aLOG 20587.
- Plot comparisons between both models, and make sure it makes sense.
- Figure out how to handle "the feedback minus sign" convention, to confirm that we're both obeying what's shown in LHO aLOG 21601

C. Cahillane

I have posted my latest uncertainty components plots including the propagated Actuation and Sensing Uncertainty:
I have also deflated my kappa uncertainties to 3% and 3 degrees:

σ_|A_tst| = A_coeff_sigma_mag_A_tst .* abs(A_tst);  
σ_|A_pu| = A_coeff_sigma_mag_A_pum .* abs(A_pum) + A_coeff_sigma_mag_A_uim .* abs(A_uim);
σ_|C_r| = C_coeff_sigma_mag_C_r .* abs(C_r);
σ_|kappa_tst| =  3;
σ_|kappa_pu| = 3;
σ_φ_A_tst = A_coeff_sigma_phase_A_tst;
σ_φ_A_pu = A_coeff_sigma_phase_A_pum + A_coeff_sigma_phase_A_uim;
σ_φ_C_r = C_coeff_sigma_phase_C_r;
σ_φ_kappa_tst = 3;
σ_φ_kappa_pu = 3;
σ_kappa_C = 3;
σ_f_c = 23.4731;

We have very high phase uncertainty above 1000 Hz due to our large systematic error in our sensing phase there.  Recall that I have simply quadratically summed our systematics and statistics into a single uncertainty expression, and that this is giving up valuable info on our error!
Otherwise, we have reasonable error even for 3% and 3 degrees uncertainties in the kappas.

15:00 UTC Handoff from Nutsinee. IFO in observing mode.
16:46 UTC Jeff B. to mechanical room to check fitting on pump
16:47 UTC Gerardo getting trailer and attaching to pickup truck
16:49 UTC Jeff B. back
16:58 UTC NORCO technician here
17:00 UTC NORCO technician through gate
17:04 UTC Gerardo taking NORCO technician to end X, pressure testing LN2 dewars on way back towards vertex
17:04 UTC Out of observing
17:16 UTC Back in observing
17:17 UTC Helicopter flyover
17:37 UTC Gerardo at end X, going to mid X
~17:44 - 17:50 UTC Gerardo reports hearing shelling from Yakima firing range
17:57 UTC Tour in control room
18:26 UTC Gerardo and NORCO technician at corner station. Will move towards end Y
19:45 UTC Helicopter flyover

Still in observing mode at ~ 70 Mpc.

~ 19:45 UTC Went outside to look. Seemed to pass over Y arm near corner station heading toward inside of arm vertex.

A tour group was on site this morning.  Arrival time at LSB = ~9:00 AM.  Departure time = ~11:45 AM.  Group size = ~20 adults.  Vehicles at the LSB = ~7 passenger cars.  The group was in the control room near ~11:00 AM and on foot near the overpass near 11:30 AM.

17:17 UTC Heard what turned out to be a helicopter flying overhead. Gerardo says he saw it come within half a mile of end X. We were in observing mode.

17:04 UTC Taking out of observing so Gerardo can take LN vendor along X arm. (WP 5504)

STATE Of H1: Observing
OUTGOING OPERATOR: Nutsinee
QUICK SUMMARY: Winds less than 20 mph. Lights off in LVEA. Lights appear off in PSL enclosure. Lights appear off at mid and end stations.

RickS, SudarshanK, CraigC, JeffreyK, DarkhanT

To calculate DARM time-varying parameters we use EPICS records precalculated from DARM OLG TF model, as described in T1500377-v7.

Earlier we reported that EP1 calculated from the canonical DARM model for ER8/O1 had an unexplained phase discrepancy (see LHO alog 21386) that came from measured TF taken between x_tst excitation point to DARM_ERR at cal. line frequency being off by -136.7 degrees compared to TF calculated accoring to Eq. 5 in T1500377 from DARM model. In this alog we outline current status of our investigations of this discrepancy.

The negative sign of the DARM feedback loop that was shown on the simplifed DARM loop diagram in T1500377-v7 was not placed where it actually appears. This update affects only how x_tst line to DARM_ERR (and DARM_CTRL) TF is calculated in the DARM model; Pcal and x_ctrl line to DARM_ERR (and DARM_CTRL) TF equations remain valid in T1500377-v7.

Figure below shows the correct location of the sign flip of the DARM loop (that's not included into C, D or A) accroding to our investigations; we'll update T1500377 with the correct diagram in the next version. (notice that this simplified diagram, as it was cited in T1500377, was borrowed from G1500837 where it might also need to be corrected)

In ER8/O1, since now we have x_tst (ESD) calibration line that is injected from the suspension front-end model (inside of the block "A" on the diagram), additional to the knowledge that the sign flip is between the x_ctrl (DARM line) excitation point and ΔL_ext, we also need to know the location of it w.r.t. the x_tst excitation point.

With the -1 sign flip placed in the new location Eq. 5 and Eq. 7 in T1500377 should not have a "-1" factor. Hence, Eq. 19 will also not have a "-1" factor, meaning that our calculation of EP1 was incorrect by 180 degrees.

Currently there's an unexplained +44.4 degrees of discrepancy (instead of earlier -136.7) between measurement x_tst / DARM_ERR vs. the model itself, that appears in EP1 (we looked into the measurement of x_tst / DARM_ERR on Sep. 10). We are investigating the source of this discrepancy.

The location of the sign was confirmed by using measurements of

• L3 stage (ESD) driver excitation to DARM_IN1 TF,

meas. file: CalSVN/Runs/ER8/H1/Measurements/FullIFOActuatorTFs/2015-08-29/2015-08-29_H1SUSETMY_L3toDARM_LVLN_LPON_FullLock.xml

• input of "D" to input of "A" (exported from canonical DARM OLGTF measurement)

meas. file: CalSVN/Runs/ER8/H1/Measurements/DARMOLGTFs/2015-09-10_H1_DARM_OLGTF_7to1200Hz.xml

• input of "A" to output of "C" (exported from canonical DARM OLGTF measurement)

meas. file: CalSVN/Runs/ER8/H1/Measurements/DARMOLGTFs/2015-09-10_H1_DARM_OLGTF_7to1200Hz.xml

Attached is agallery of 5 "dust" glitches. Still clueless of what they are, but
 - ETMY saturation is a symptom, not a cause  - it is not possible to produce such a white glitch from saturating a drive.
 - The DCPD spectrum shows a roll-off for all of them
 - But the roll-off frequency (i.e. glitch duration) varies significantly = from about 300Hz to 3kHz.


Example 2:
GPS: 1126294545
UTC: Sep 14 2015 19:35:28 UTC
ETMY saturation: yes

Example 3
GPS: 1126437892
UTC: Sep 16 2015 11:24:35 UTC
ETMY saturation: yes

Example 4
GPS: 1126434798
UTC: Sep 16 2015 10:33:01 UTC
ETMY saturation: yes

Example 5
GPS: 1126441165
UTC: Sep 16 2015 12:19:08 UTC
ETMY saturation: yes

Example 6
GPS: 1126442379
UTC: Sep 16 2015 12:39:22 UTC
ETMY saturation: yes