Expect to remove BSC9 West door in the morning for a brief incursion by others followed by door install and pump down.
WIth Rick's help, we have created a composite image of ETMy before, after, and before-minus-after using Matlab. Due to saturation of the camera's photodetector in the 'after' photo (we believe due to higher power in the arm), the particles we removed during cleaning appear magenta. Tomorrow, I hope to do the same with the IR photos.
I think Travis meant to say "before photo" rather than "after photo." We suspect that the purple color comes from the fact that in the "before" photo the large scatterers were saturating the image at this exposure, as indicated by the bright white fields in the image. In the "after" photo, we subtract a fair amount of the green light due to the diffuse background scatter which is perhaps brighter due to the higher circulating power resulting from the reduction in losses. Removing most of the green leaves the red and blue for the saturated scatterers, rendering them purple.
Rick is correct, 'after' should be 'before'. I also meant that the appearance of more green light scattering in the 'after' photo is likely due to more arm buildup. Apologies for any confusion induced.
I repeated the measurement from alog 15783, just checking coherence between HAMs 2&3 after we changed HAM3 to look at the right seismometer. Nothing obvious, but I found something interesting. The FIR_IN signals should all be the exactly same at this point, and so should be 100% coherent, between the chambers. The Z signal is not, but the difference is only below 50 mhz, at around .6hz the coherence is almost 100% again. Attached plot shows measurement from the middle of last ni.
Sensor correction is off on HAMs 2&3, I will leave it off on these chambers overnight. I'm also switching the cables on the AA chassis at the rack for STS-A. Will swap back tomorrow morning.
LVEA: Laser Hazard Observation Bit: Commissioning 07:30 Karen & Cris – Cleaning in the LVEA 09:05 Aaron & Filiberto – In LVEA cabling work at HAM3 & BS 09:25 Mitch – Working in LVEA West Bay cleanroom 09:43 Hugh – Working in LVEA West Bay area 09:44 Jim & Sebastien – In CER working on HAM2 Electronics 09:53 Andres & TJ – Working on 3IFO Quad storage modifications 10:25 Manny – Cable work around H2 electronics test stand 10:37 Filiberto & Aaron – Finished pulling cables at HAM3/BS. Started terminating these cables 10:50 Sheila – Transition End-X to laser safe 11:36 Jim & Sebastien – Back in CER working on HAM2 Electronics 11:45 Mitch & Hugh – Out of the LVEA 12:48 Manny – Pulling cables around H2 electronics test stand 14:35 Kyle – End-X to prep for vent 15:16 Kyle – Going to End-Y 15:28 Kyle – Going back to End-X
The attached plots are from the period when there were 4 people working in the PSL enclosure on Monday (01/05/15) between 09:00 and 13:00.
Took DBB scans of the PSL this afternoon. Plots are posted below
I had to restart the replication of the h1conlog database on h1conlog3. The replication thread timed out waiting to acquire a lock. The reported errors are attached. I am investigating.
We communicated the major crane movements with the control room commissioners. No unusual problems. Two BSCs and five HAMs to go.
Alexa, Thomas, Evan
Conclusion: it appears that we are at a good low loss point for the IR without having to adjust the green QPD offsets.
I locked both the IR and green to the Yarm. The alignment steps I took were the following:
1. I ran the ditherAlign.py script to center the TMSY pointing using the ITM baffle PDs.
2. I had to walk ITMY, ETMY to get high enough flashes in the arm cavity, and then was able to lock the arm on green and engage the green wfs (all 6 DOFs). This brought the green TR buildup to 1.024 cnts.
3. I then locked the IR to the Y arm and engaged the input pointing wfs to PR2, and IM4. This brought the IR TR buildup to 11 cnts.
At this spot, I measured the LSC-ASAIR_A_LF _OUT counts and found Poff = 1304(5) and Pon = 1262(4), this gives an equivalent ETM loss of L = 125(19) ppm. This was calculated following the equations in alog 15874 and 15470. This is a low enough loss spot, and both the IR and green TR buildups are high. I did not have to adjust the QPD offsets (i.e. adjust the green input pointing).
Evan and I were trying to figure out why these results are better than the previous ones in alog 15874. For one the green wfs were not enabled, although the green TR buildup was similar. We are going to repeat this measurement over a few mornings and see how consistent of a loss we get with this alignment procedure.
Attached is a plot of EX over the past 30 hours.
J. Kissel Daniel's "posted without comment" .pdf reveals a couple of weird things that may incline some to say things like "oh! there's a change there! What's that jump? Doesn't it now look like it's turning up like the other chains?" Don't get caught up in that game. This is the game we've said we'll be playing for weeks. The test mass has still only displaced 5 [um] at most. We need to go more than 100 [um]. Further -- the test mass is *still not free*. I attach transfer functions taken just after this trend was posted. It's still frozen, the TFs look the same as the have since we first started measuring in this year (see LHO aLOG 15878).
Most of the meeting focused on discussion for a possible EX vent.
Majority of meeting spent on discussion about OSEM issue at EX, gaps for EQ stops, will decide about EX incursion after SUS meeting.
No Such thing as a "Quick Vent": Even for a QUICK task in-chamber, EVERY vent has BIG effects (time, contamination, making things worse, etc.)
Will go over Work Permits on Fri
Jim and Dave.
The SUS team brought a DAQ problem to our attention. When viewing minute trends vs second trends for a time period covering yesterday morning/afternoon the two plots did not have the same data. The minute trends are complete, the second trends have data loss. We determined the second trends showed data up to the DAQ restart at 12:36PST and then for part of the last hour. Strangely, only channels from the FE computers showed this data loss, channels from the EDCU showed second trend data over the entire time period. If the second trend time period does not include the DAQ restart, data is shown (i.e. no data is actually lost). Jim determined that this appears to be an NDS and not a dataviewer problem, we are investigating. The work around is to get the second trends in two requests, up to the DAQ shutdown (12:30 PST) and from the DAQ restart (12:40PST).
model restarts logged for Tue 06/Jan/2015
2015_01_06 11:05 h1iopsusauxey
2015_01_06 11:05 h1iopsusey
2015_01_06 11:05 h1susauxey
2015_01_06 11:05 h1susetmy
2015_01_06 11:05 h1sustmsy
2015_01_06 11:58 h1sustmsy
2015_01_06 12:01 h1sustmsx
2015_01_06 12:04 h1susim
2015_01_06 12:08 h1sushtts
2015_01_06 12:10 h1susmc1
2015_01_06 12:12 h1susmc3
2015_01_06 12:14 h1susprm
2015_01_06 12:19 h1susmc2
2015_01_06 12:19 h1suspr2
2015_01_06 12:22 h1sussr2
2015_01_06 12:26 h1sussrm
2015_01_06 12:27 h1susomc
2015_01_06 12:36 h1broadcast0
2015_01_06 12:36 h1dc0
2015_01_06 12:36 h1fw0
2015_01_06 12:36 h1fw1
2015_01_06 12:36 h1nds0
2015_01_06 12:36 h1nds1
2015_01_06 16:11 h1nds1
2015_01_06 16:12 h1nds1
2015_01_06 16:13 h1nds1
X1PLC1 10:01 1/6 2015
X1PLC2 10:01 1/6 2015
X1PLC3 10:01 1/6 2015
Unexpected restarts of h1nds1, possibly related to data requests.
Maintenance Day. FE, DAQ and Beckhoff restarts shown. h1susey and h1susauxey ADC work. New models for non-quad SUS with associated DAQ restart. h1ecatx1 did its usual Tuesday freeze up.
J. Kissel For the record, I've moved H1 SUS BS and H1 SUS PR2 to MISALIGNED via the guardian, for no other reason that everyone has gone home and the giant projection of the AS port was giving me a seizure from interference flashes thanks to the 6.6 [mag] earthquake in Panama. Please restore at your leisure in the morning.
Kiwamu, Alexa, Koji, Evan
For the past few days, it has been difficult to lock MICH on a dark fringe; the velocity of the BS quickly becomes too high. Kiwamu found that turning down the gain from −500 ct/ct to −200 ct/ct during lock acquisition helps this situation; also, once locked, engaging FM2 and FM3 (rather than FM3 and FM6) seems to have a higher probability of success for keeping the Michelson locked.
Trying to transition to DRMI_1F_LOCKED_ASC in the ISC_DRMI guardian will blow the lock. This appears to come down to the INP1 and PRC1 loops; the others (PRC2, MICH, SRC1, SRC2) can be engaged by hand just fine. INP1 controls PRM and IM4, and PRC1 controls just PRM. I tried locking with lower gain, with opposite sign, with the PRM M1 bleed-off disengaged, etc., but could not close either loop stably. We'll need to take a deeper look at why these loops no longer work.
With DRMI locked on 1f, Koji and I took an RF spectrum of REFLAIR_B, using the −12 dB coupler on the diplexer (as in LHO#14796). This is the first measurement of the RF spectrum of REFLAIR_B after its modification (LHO#14925).
Initial Alignment
We also had some problems running the PRM_ALIGN and SRM_ALIGN via the ISC_DOF guardian. The PRM_ALIGN takes a while to bleed off from the M3 to the M1 stage, and thus to offload. We tried going back to the old version of PRM_ALIGN in which we only feed the wfs back to M1; however, we did not succueed -- a lot of settings had been changed and we could not remember the old configuration; we didn't spend too much time trying to debug. We also ended up aliging SRM by hand which turned out to be faster. We should take some time and look at these scripts since a lot has been changed.
BBPD spectrum taken. -12dB coupling has already been compensated. Note that the removal of one of the BBPD preamps reduced the PD gain by ~20dB.
Condition:
H1:LSC-REFLAIR_B_LF_INMON 17000+/-2000
H1:LSC-REFLAIR_B_LF_OUTPUT 17.8+/-0.2 mW
H1:LSC-POPAIR_B_RF18_I_MON 350+/-5
H1:PSL—PERISCOPE_A_DC_POWERMON 10620+/-20
Using the newly setup PCal capabilites from the Control Room (thanks Dave!), I took some new photos of the ETMy optic post FC cleaning. Although the IR only image is out of focus (I will take a new one tomorrow after refocusing the camera), the improvement if fairly evident. The first photo is with green only locked, second photo is with IR only locked. I used the same camera settings as were used pre-cleaning (F8, ISO 200, 30 sec. exposure, WB-cloudy).
For easy comparison, see attached composite photo pre-cleaning. ETMy is the right hand set of photos.
As promised, a more in-focus post-cleaning IR locked ETMy image .
Sheila, Thomas, Elli, Evan
We locked the Y arm in IR, and then turned on WFS loops which feed back to IM4 and PR2 in order to keep the buildup in the arm maximized. We measured the dc counts on ASAIR_A_LF. Then we unlocked the arm and measured ASAIR_A_LF again. The results are as follows:
Using the formula in LHO#15470, the locked and unlocked values of ASAIR give an equivalent loss of 267(31) ppm on ETMY.
To account for the power in the sidebands, we use the modulation depths given in LHO#15674: Γ9 = 0.219(12) and Γ45 = 0.277(16). Then the power in the sidebands is PSB = Poff × (Γ92+Γ452)/2 = 81(7) ct. Then using our new value for the power fraction, A2 = (Pon − PSB)/(Poff − PSB), we get an equivalent loss of 286(33) ppm on ETMY, not accounting for mode mismatch.
We also took loss scans by moving spot on ETMY in a spiral pattern, as in LHO#15476. The sideband power is subtracted here as well. It appears that judicious alignment of the arm may give us lower loss (something like 140 ppm), compared to the number reported above.
In the attached plot, I've masked out data points for which the transmitted power was below 11 ct.
As before, the zero point of the displacement is somewhat arbitrary; we performed the usual initial alignment sequence for the arm (baffle PDs for TMS and the ITM, then maximize the buildup of the green power), but didn't attempt to determine the location of the spots on the test masses.
Also note that for the formula in LHO#15470, the physically meaningful solution requires us to take the negative branch of the square root when computing A (so substitute A → −A in this formula).
