Please log excursions to Y end. If you look on OPWS0 you can see if it is still running. It will likely be done fairly early SaturdayAM so you'll mostly be in the clear. Call me-619-3304.
J. Kissel, A. Pele We had a huge wind storm (30 mph average, 50+ mph gusts) this afternoon that was taking down HEPIs and ISI left and right. Moving the blend UP didn't help. We decided to just leaving the ISIs off for a bit just to gather environmental data and watch the storm roll by, since no interferometry could be done. For 1 hour, starting at GPS 1078868350, Mar 14 2014 21:38:54 UTC, For ITMX and ITMY HEPI - isolation level 1, 'pos' blends ISIs - Damping Only QUADs - Damped After an hour or so, HEPI ITMX tripped. As of Mar 15 2014 00:40:00 UTC, all 4 BSC chambers have been left at their believed to be best performance during low-wind times: HEPI - isolation level 1, 'pos' blends ISIs - isolation level 3, 'TCrappy' Blends QUADs - Damped
Got the CPS racks grounded and wired up. Fine tuned the Dial Indicators. Still need to do some cable strain relief but I'm out of hardware and this is not the only place that is needed.
Ready for chamber cleaning to prep for opening.
I ran a few static tests yesterday on ETMY HEPI. Things like linearity & range of motion etc. Attached is a two plot of trends on the HEPI Cartesian basis IPS. X & Y have moved a few ums while Z and Rx & Ry are pretty steady. Rz has rotated a little more now out to 22urads. Again this is good for the alignment now as long as it doesn't go further.
Dave, Stefan We tried a PRX length measurement, but had to conclude that - REFL is swamped with the direct reflection signal - the expected broad bump is not visible. - POP has too much attenuation - he do not see a beat note at all. The interferometer is thus available for the rest of the night.
All actuator sub assemblies have been completed. Time with Jim is required to add these sub assemblies to the ISI. All of the flexure sub assemblies 0-1, and 1-2 have been completed. The granite table has been cleared in preparation for monolithic plates, which were brought over to the staging building this afternoon by Apollo.
Clean-up of RGA is slow at the reduced temperatures used -> RGA is isolated from the BT via (2) series-connected closed 1 1/2" valves
6:20 -> Working at End X – Jodi 7:20-8:10 -> Heading to End Y – Jodi 8:45-9:10 Going to End Y to work on dust monitor – Jeff.B 9:01-11:54 HEPI work on HAM5 - Hugh 9:15-9:30 Dust monitor work by HAM5 (LVEA) – Jeff.B 9:24- Going to End Y – Travis 9:30-10:00 End Y cleaning - Karen 9:35 -> PSL Check List (OK) 10:16-13:39 H2 Laser enclosure work – Gerardo 10:38-11:04 Working on SR3 (LVEA) – Jeff B. 10:43-11:30 Searching for cables at Mid Y – Filiberto 10:45-12:35 Going to End X (cleaning) - Cris 11:20 -> Laser turned ON at End Y – Rick S. 11:30 -> LVEA transitioned to Laser Hazard - Justin 13:20-14:30 Back to HAM 5 – Hugh 13:30- Working at End X – Keita 13:58- Joining Keita at End X – Sheila 14:08- In LVEA working on nitrogen piping - Apollo
Travis, Margot, and Kate
Removed the horizontal 4" wafer from the beamtube (between the purge air port and ACB). The 1" optic that was placed with the wafer couldn't be removed (no PETG containers available), so it was moved to the opposite tube for the time being. When possible, it should be moved back to its original location or removed. A new 1" optic (s/n 1195) was mounted vertically to the QUAD.
Refer to Betsy's earlier alogs on contamination in BSC10 (10522, 10675 & 10686). There is still a lot of particulate contamination, even after cleaning. The first photo shows a wipe used to clean the tube on Monday. Dust, metal, a few red fibers, and white fuzzies were observed on the tube floor from the ACB all the way to the PCAL periscope. The iphone photos and videos don't really do it justice. There was a much higher concentration of white fuzzies along one half of the tube (on the right side, if you have your back to the ACB and are facing the periscope). Travis took an FBI sample, and then vacuumed the area.
After finishing PCal alignment, I replaced the 1" optic to it's original position between the purge air port and the ACB/ETM. I then wiped my way out of the chamber.
We've had at least 6 times this morning that HEPIs have tripped on the L4Cs, and there isn't a clear reason looking at the seismic conditions why today should be worse than other days. The chambers that have tripped are (at least ) IMTX twice, ITMY once, HAM2 once, BS twice. Attached are plots of the two most recent BS trips.
No one on site really has the time to sort through the data and figure out what is happening, is there anyone from SEI or DetChar that can take a look?
Thank you,
Sheila
Sheila,
thanks for the note. We start looking into it. Since the L4C are not even in the loop, please feel free to temporarily rise the WD value (the code will slowly bring it back to standard value at teh rate of 1 ct/s or so).
We get back to you asap.
Dust monitor #2 at End-Y (next to the BSC10 chamber) and dust monitor #1 in the HMA5 cleanroom are both online and functional.
It didn't seem like there was much seismic noise based on the PEM FOMs, but they both triped around the same time. Plots for ITMX attached
This time ITMX and ITMY both tripped again at the same time. Here are plots for IMTX again, Robert was making an injectiong at this time but he doesn't think it should have tripped the ISI. There isn't much in the PEM FOMs again.
2014_03_13 16:14 h1ioppemmy
2014_03_13 16:15 h1ioppemmy
2014_03_13 16:18 h1ioppemmy
2014_03_13 16:22 h1ioppemmy
2014_03_13 16:48 h1ioppemmy
2014_03_13 16:50 h1pemmy
no unexpected restarts.
Laser Status: SysStat is good Output power is 28.4 W (should be around 30 W) FRONTEND WATCH is Active HPO WATCH is red PMC: It has been locked 2 d, 11 h 15 minutes (should be days/weeks) Reflected power is 1.2 Watts and PowerSum = 11.3 Watts. (Reflected Power should be <= 10% of PowerSum) FSS: It has been locked for 0 d 0 h and 5 min (should be days/weeks) Threshold on transmitted photo-detector PD = 0.9 V (should be 0.9V) ISS: The diffracted power is around 13.4 % (should be 5-15%) Last saturation event was 2 d, 11 h and 15 minutes ago (should be days/weeks)
Chris ran the swiffer in the Diode Room this morning for the first time in 8 months. Will try to make cleaning more regular.
Offending Y2P peak between 1 and 2Hz (pink) was removed after a new decoupling filter was put in place (green).
In the H1:SUS-ETMX_L2_DRIVEALIGN_Y2P filter, I put the same invP2P filter in FM1 as in the P2P path, then added a diagonalization filter ("Y2Pdiag") in FM2, and another filter that is a 3rd order elliptic BP in FM3. I didn't try to remove 0.4-0.5Hz Y2P peak, it's not great but probably good enough.
ITMX PUM P2Y and Y2P measurement was done, but I need to leave before generating decoupling filter.
Seems like ITMX PUM is somewhat better diagonalized than ETMX PUM, but I'll remove 1.4Hz P2Y peak anyway.
Remember, the ITM is a wire hang QUAD (the test mass is suspended from the PUM via a wire loop and prisms), and has significantly different dynamics than the ETM fiber welded QUAD. This may be an explanation for the different dynamics. I also imagine you'll have to do this process all over again with the ITM once it becomes monolithic like the ETM.
We probably need to re-do everything once it's re-hang.
