Koji requested 10W of laser power for HAM6 alignment work. Set Guardian LASER_PWR node to 10W and re-enabled the rotational stage.
SEI: No Issues SUS: Model restarts. HAM6 Vent work ELE: Cabling in LVEA, working on binary I/O card for PSL PSL: No Issues. TCS needs ITMY to finalize replacement of RF Driver VAC: Replace Annulus Ion Pump at GV3. Replace gauge at HAM6 when OMC work is finished. The HAM6 doors will go on either late Monday or Tuesday morning. There will be a film crew on site Tuesday, Wednesday, and Thursday. Ops will start evening shifts when HAM6 work is finished. Did work permit review.
J. Kissel, E. Hall, E. Goetz I'm reconciling the SDF system for PCALY, and I've found a difference in the amplitude of the 331.9 Hz line. After speaking with Evan Hall, he had been commissioning with the line a month or so ago with an abnormally large amplitude of 30000 [ct] (see LHO aLOG 28702), and accidentally left it in place. Since then, someone had blindly accepted this value in the SDF system. I've now reverted it to the O1 amplitude of 2900 [ct] (see e.g. LHO aLOG 27981). For future reference, all calibration lines that are on and present in the system: Channel Names _FREQ (Hz) _SINGAIN (ct) H1:CAL-PCALY_PCALOSC1_OSC 36.7 125 O1-scheme kappa_TST / kappa_PU H1:CAL-PCALY_PCALOSC2_OSC 331.9 2900 O1-scheme kappa_C / f_CC H1:CAL-PCALY_PCALOSC3_OSC 1083.7 15000 high-frequency calibration check ("bonus" line) H1:CAL-PCALY_PCALOSC1_OSC 3501.3 39322 high-frequency sensing function characterization ("mobile" line) _FREQ (Hz) _CLKGAIN (ct) H1:SUS-ETMY_L1_CAL_LINE 33.7 11 O2-scheme synched oscillator for kappa_U H1:SUS-ETMY_L2_CAL_LINE 34.7 1.1 O2-scheme synched oscillator for kappa_P H1:SUS-ETMY_L3_CAL_LINE 35.3 0.11 O2-scheme synched oscillator for kappa_T H1:SUS-ETMY_LKIN_P_OSC 35.9 0.11 O1-scheme kappa_TST / kappa_PU
Surveyed all viewports at LVEA, EX, EY. Several viewport lexan housings in LVEA are missing tabs. FRS report filed. Vacuum group will order more tabs from machine shop and install these.
Results of degassing PT170 & PT180 nude ion gauges in corner station are attached. Total pressure reading dropped slightly. Note: the corner was/is currently isolated from two cryopumps with GV 5 & 7 closed.
VBOB bake good, Corner Station vent/purge air supply normal for current conditions of 38F chilled water supply and 1/8th turn closed (from nominal 1/4 turn open) manual coolant valve (1 of 2 - not the after cooler valve), 1st STAGE AIR DISCHARGE 296F 2ND STAGE AIR SUCTION 82F 2ND STAGE AIR DISCHARGE 280F LUBE OIL 126F Did not measure dew point at HAM6 but observed drying tower switching. No alarms. Y-end RGA bake good > 160C everywhere on RGA side and tapering off to 70C @ the turbo inlet and the 4.5"-10" CFF BSC6 interface, 1610 hrs. local -> Leaving site now.
Thanks for checking on the purge air, Kyle.
1415 - 1425 hrs. local -> To and from Y-end checking RGA bake that was started Thursday morning (discovered that I don't have a WP for this! Will initiate one today and ask for forgiveness later - its easier than getting permission!) GV3 AIP died -> will address during the week. Will make comment to this entry when leaving site.
Added 3rd variac to Y-end RGA bake so as to enable control of Cal-Gas bottle zone independent of other parallel heated zones. Also added a fan for the scroll pump. VBOB bake good. Corner Station vent/purge air supply also good. Temps, pressures same as yesterday but dew point a little higher at -30C. 1745 hrs. local -> Leaving site now.
Ansel and I put the end station CPS timing fan outs on separate +/-18V power this evening in hopes of eliminating the comb of odd harmonics of 1 Hz in DARM. A similar comb had been evident in the magnetometer that I set up at the EY ESD to look for blip glitches, and it went away when we powered the fan out with a separate supply. We think that this is because the magnetometer was detecting ripple in the field radiated from the +/-18V connector on the low V ESD drive and that we eliminated the ripple on ESD power by powering the CPS timing fan out on a separate supply. For this reason we varied from the work permit and didnt put them in a different rack. Ansel will fill in details of the studies he did that made us think that this is the source of the comb (especially if it really does go away in DARM), but we think that the comb isn’t GPS synched because it is driven by a clock on the PSoC board of the CPS timing fan out. Isolation of BSCs 9 and 10 has been restored to nominal.
Ansel Neunzert, Robert Schofield
This shouldn't be right. The PSoC board is supposedly clocked by half of the provided 71 MHz signal. However, looking at the photos on E1400155 I see that the 2 crystal oscillators of the development are still soldered in. Please tell me this is not true for the units installed in the field.
Tagging SEI and CDS.
Our understanding of the electronics is based on the same DCC document/photos that Daniel linked to.
Some background info on what led us here: the comb was first reported in May by Brynley Pearlstone (alog), and again by Keith Riles in his ER9 narrow lines report (alog). Per Keith's report, the spacing is 1.999951-Hz, visible on approximate odd-integer-Hz frequencies. Robert and I looked back in older data for its appearance, and isolated the date range between February 26 and April 2, but there was not enough good DARM data in that window to track it further. Turning to magnetometer data, we found the comb in a channel at EX (H1:PEM-EX_MAG_VEA_FLOOR_X_DQ), and tracked its appearance down to March 14th using data from that channel (with help from one of Keith's students, Eilam Morag, who has written code for tracking the strength of known combs). We initially suspected the computer system restart on that date, but have not found evidence to support this hypothesis by examining data around subsequent restarts. As a second guess, we looked into the changes to the CPS timing system made on that date (alog) (both end stations). Coincidentally, Robert had placed a magnetometer in the CPS rack at EY to search for blip glitches, and this magnetometer showed the comb strongly, which motivated us to look into the CPS timing fan out.
In the PSoC software, you can select where its clock comes from. They are clocked from 1/2 the site 71MHz. The oscillators are not removed from the board, just de-selected from the clock menu in software.
[Corey, TJ, Betsy, Koji]
RESOLVED ISSUES:
- The issue of the suspension TF was resolved by adjusting one of the OMC EQ stop holders [LHO ALOG 28900]
- The sign-flip issue of the DCPD signals has been explained by the accoustic noise of the OMC [LHO ALOG 28901]
PROGRESS:
- The lock nuts of the upper mass EQ stops were fastened (by fingers)
- The black glass panels of the OMC shroud were restored. We checked the input/reflection apertures to be well aligned against the beams.
- The OMCT steering mirror was restored to the optical mount.
- The alignment of the WFS path was reviewed. It was found that the path is still well aligned. Just the WFS QPDs were manually aligned by the mounts with picomotors.
- We attached the viewport simulator on the flange to check the alignment of the in-air paths. The AS AIR path was very well centered on the viewport without touching. The OMCR path is about 50% towards East (-Y) from the center of the viewport. We could not find the OMCT spot no matter how we flash the OMC. This could be just the beam was too dim, or was blocked by the shroud. We'll investigate this on Monday again.
TO DO:
- Continue to work on the OMCT path alignment. This requires ~10W IMC input. Try to find a dim flashes. Use a CCD camera on a tripod to find the spot around the viewport cover.
- We want to check the calibration between AS_C QPD SUM, the incident power on OM1, and the incident power on the OMC breadboard.
- Other ISC items function check (picos, beam diverters, fast shutter - see Rich's comment below, etc)
- Ground loop check
- Other SUS/SEI exit check
J. Kissel Now that the re-assembly of the OMC is complete including EQ stop spacing, EQ stop lock-nut securing, and OMC shroud replacement, I've reconfirmed that the dynamics of the OMC SUS are still free-and-clear as they were this afternoon. Nice work Koji and co.! There is no further planned installation work in and around the OMC SUS, so we suspect these will be the last full in-air transfer functions before chamber close-out next week. Templates live here: /ligo/svncommon/SusSVN/sus/trunk/OMCS/H1/OMC/SAGM1/Data/ 2016-08-06_0007_H1SUSOMC_M1_WhiteNoise_L_0p02to50Hz.xml 2016-08-06_0007_H1SUSOMC_M1_WhiteNoise_P_0p02to50Hz.xml 2016-08-06_0007_H1SUSOMC_M1_WhiteNoise_R_0p02to50Hz.xml 2016-08-06_0007_H1SUSOMC_M1_WhiteNoise_T_0p02to50Hz.xml 2016-08-06_0007_H1SUSOMC_M1_WhiteNoise_V_0p02to50Hz.xml 2016-08-06_0007_H1SUSOMC_M1_WhiteNoise_Y_0p02to50Hz.xml Note, I've finally listened to my own advise and made sure that these in-air transfer function templates all have the same frequency resolution and excitation amplitude and coloring.
While HAM6 is open, it would be good to do a close inspection of the fast shutter. Specifically the wires attaching the bobbin (toast) to the integral terminal block. These wires are tiny and are the most likely item to fail. Also good to check for any delamination of the mirror to the bobbin.
Photos from Friday's work is on Resource Space here:
https://ligoimages.mit.edu/?c=1703
9:30AM FRI AUG 5th, 2016 - Chamber entrance Particle counts with hand held CC counter:
| Particle size | Outside of chamber cover, in CR | In chamber above table |
| 0.3um | 60 | 25 |
| 0.5um | 20 | 10 |
| 1.0um | 0 | 0 |
1:30PM FRI AUG 5th, 2016 - Chamber entrance Particle counts with hand held CC counter:
| Particle size | Outside of chamber cover, in CR | In chamber above table |
| 0.3um | 60 | 0 |
| 0.5um | 0 | 10 |
| 1.0um | 0 | 0 |
Purge air has been mysteriously throttled to a "trickle" going into HAM6 (no longer my battle)
We adjusted it on Friday in hopes to get a better OMC measurement. I thought that I had brought it back to its previous state but with how touchy that valvue is, I may have been slightly off.
