ID |
Date |
Author |
Type |
Category |
Subject |
1634
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Sat May 30 12:36:52 2009 |
rob | Update | Computers | c1susvme2, c1iscex running late |
c1susvme2 has been running just a bit late for about a week. I rebooted it.
The plot shows SRM_FE_SYNC, which is the number of times in the last second that c1susvme2 was late for the 16k cycle. Similarly for ETMX.
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Attachment 1: srmsync.jpg
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Attachment 2: etmxsync.jpg
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1633
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Sat May 30 12:03:34 2009 |
rob | Update | PSL | MC locked |
I locked to PSL loops, then tweaked the alignment of the MC to get it to lock.
I first steering MC1 until all the McWFS quads were saturated. This got the MC locking in a 01 mode. So I steered MC1 a little more till it was 00. Then I steered MC2 to increase the power a little bit. After that, I just enabled the MC autolocker. |
1632
|
Sat May 30 11:24:56 2009 |
rob | Configuration | PSL | NPRO slow scan |
I'm setting SLOWDC to about -5.
I had to edit FSSSlowServo because it had hard limits on SLOWDC at (-5 and 5). It now goes from -10 to 10.
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Attachment 1: slowSCAN.png
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1631
|
Fri May 29 18:57:09 2009 |
steve | Update | PSL | the laser is back |
Steve, Rob and Alberto
Starting capacitor 216 miroFarad was installed on the compressor. Water lines were connected to the MOPA as corrected, so the flow meter readings are logical.
Now IN means flowing water in the direction of black arrow on the hose.
We struggled with the Neslab presetting: temp, bauds rate and other unknowns till Rob found the M6000 manual on Peter king's website.
Alberto realized that the chiller temp had to be reset to 20C on water chiller.
I put 1mg of Chloramin T into the water to restrict the growth of algae in the bath.
The NPRO heat sink was around ~20C without flow meter wheel rotation and the PA body ~25C by touch of a finger
I just opened up the needle valve a litle bit so the flow meter wheel would started rotating slowly.
That small glitch at the end of this 3 hrs plot shows this adjustment. |
Attachment 1: laserisback.jpg
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1630
|
Thu May 28 18:41:26 2009 |
steve | Update | PSL | the saga of the chiller is ending |
I drained the water and removed side covers from the Neslab RTE 140 refrigerated water cooler unit this morning. The hoses to the laser were disconnected.
This abled you to see the little window of refregerant R404A was free of bubles, meaning: no recharge was needed.
The circulator bath was refilled with 7 liters of Arrowhead distilled water and the unit was turned on.
The water temp was kept 20.00+- .05C without any load. Finally the AC-repair man Paul showed up.
He measured the R404A level to be as specified: 23-24 PSI on the suction side and 310 PSI on the discharge side.
The unit was working fine. Paul found an intermittently functioning starting capacitor on the compressor that was removed.
The 240 micro Farad 120VAC cap will arrive tomorrow |
1629
|
Thu May 28 14:34:25 2009 |
rob | Update | PSL | chiller diagnosis |
Quote: |
steve, alberto, rob
After some futzing around with the chiller, we have come to the tentative conclusion that the refrigeration unit is not working. Steve called facilities to try to get them to recharge the refrigerant (R-404a) tomorrow, and we're also calling around for a spare chiller somewhere in the project (without luck so far).
|
The repair man thinks it's a bad start capacitor, which is 240uF at 120V. Steve has ordered a new one which should be here tomorrow, and with luck we'll have lasing by tomorrow afternoon. |
1628
|
Wed May 27 15:59:44 2009 |
rob | Update | PSL | we don't understand the chiller (broken) |
steve, alberto, rob
After some futzing around with the chiller, we have come to the tentative conclusion that the refrigeration unit is not working. Steve called facilities to try to get them to recharge the refrigerant (R-404a) tomorrow, and we're also calling around for a spare chiller somewhere in the project (without luck so far). |
1627
|
Wed May 27 10:54:09 2009 |
rob | Update | PSL | we don't understand the chiller (broken) |
Quote: |
Quote: |
steve, rob, alberto
Steve installed two rotary flow meters into the MOPA chiller system--one at the chiller flow output and one in the NPRO cooling line. After some hijinks, we discovered that the long, insulated chiller lines have the same labels at each end. This means that if you match up the labels at the chiller end, at the MOPA end you need switch labels: out goes to in and vice-versa. This means that, indubitably, we have at some point had the flow going backwards through the MOPA, though I'm not sure if that would make much of a difference.
Steve also installed a new needle valve in the NPRO cooling line, which works as expected as confirmed by the flow meter.
We also re-discovered that the 40m procedures manual contains an error. To turn on the chiller in the MOPA start-up process, you have to press ON, then RS-232, then ENTER. The proc man says ON, RS-232, RUN/STOP.
The laser power is at 1.5W and climbing.
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Rob, Alberto
The chiller HT alarm started blinking, as the water temperature had reached 40 degrees C, and was still rising. We turned off the MOPA and the chiller. Maybe we need to open the needle valve a bit more? Or maybe the flow needs to be reversed? The labels on the MOPA are backwards?
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The chiller appears to be broken. We currently have it on, with both the SENSOR and RS-232 unplugged. It's running, circulating water, and the COOL led is illuminated. But the temperature is not going down. The exhaust out the back is not particularly warm. We think this means the refrigeration unit has broken, or the chiller computer is not communicating with the refrigerator/heat exchanger. Regardless, we may need a new chiller and a new laser. |
1626
|
Tue May 26 17:34:14 2009 |
rob | Update | PSL | MOPA re-deactivated |
Quote: |
steve, rob, alberto
Steve installed two rotary flow meters into the MOPA chiller system--one at the chiller flow output and one in the NPRO cooling line. After some hijinks, we discovered that the long, insulated chiller lines have the same labels at each end. This means that if you match up the labels at the chiller end, at the MOPA end you need switch labels: out goes to in and vice-versa. This means that, indubitably, we have at some point had the flow going backwards through the MOPA, though I'm not sure if that would make much of a difference.
Steve also installed a new needle valve in the NPRO cooling line, which works as expected as confirmed by the flow meter.
We also re-discovered that the 40m procedures manual contains an error. To turn on the chiller in the MOPA start-up process, you have to press ON, then RS-232, then ENTER. The proc man says ON, RS-232, RUN/STOP.
The laser power is at 1.5W and climbing.
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Rob, Alberto
The chiller HT alarm started blinking, as the water temperature had reached 40 degrees C, and was still rising. We turned off the MOPA and the chiller. Maybe we need to open the needle valve a bit more? Or maybe the flow needs to be reversed? The labels on the MOPA are backwards? |
Attachment 1: laser_temp.jpg
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1625
|
Tue May 26 17:05:44 2009 |
rob | Update | PSL | MOPA re-activated |
steve, rob, alberto
Steve installed two rotary flow meters into the MOPA chiller system--one at the chiller flow output and one in the NPRO cooling line. After some hijinks, we discovered that the long, insulated chiller lines have the same labels at each end. This means that if you match up the labels at the chiller end, at the MOPA end you need switch labels: out goes to in and vice-versa. This means that, indubitably, we have at some point had the flow going backwards through the MOPA, though I'm not sure if that would make much of a difference.
Steve also installed a new needle valve in the NPRO cooling line, which works as expected as confirmed by the flow meter.
We also re-discovered that the 40m procedures manual contains an error. To turn on the chiller in the MOPA start-up process, you have to press ON, then RS-232, then ENTER. The proc man says ON, RS-232, RUN/STOP.
The laser power is at 1.5W and climbing. |
Attachment 1: DSC_0513.JPG
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Attachment 2: DSC_0517.JPG
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1624
|
Mon May 25 21:31:47 2009 |
caryn | Update | PEM | plugged in Guralp channels |
Guralp Vert1b and Guralp EW1b are plugged back in to PEM ADCU #10 and #12 respectively. Guralp NS1b remains plugged in. So, PEM-SEIS_MC1_X,Y,Z should now corrsp to seismometer as before. |
1623
|
Sun May 24 11:24:08 2009 |
rob | Update | Computers | elog restarted |
I just restarted the elog. It was crashed for unknown reasons. The restarting instructions are in the wiki. |
1622
|
Fri May 22 17:05:24 2009 |
rob, pete | Update | Computers | hard reboot of vertex suspension controllers |
we did a hard reboot of c1susvme1, c1susvme2, c1sosvme, and c1susaux. We are hoping this will fix some of the weird suspension issues we've been having (MC3 side coil, ITMX alignment). |
1621
|
Fri May 22 17:03:14 2009 |
rob, steve | Update | PSL | MOPA takes a holiday |
The MOPA is taking the long weekend off.
Steve went out to wipe off the condensation inside the MOPA and found beads of water inside the NPRO box, perilously close to the PCB board. He then measured the water temperature at the chiller head, which is 6C. We decided to "reboot" the MOPA/chiller combo, on the off chance that would get things synced up. Upon turning off the MOPA, the neslab chiller display immediately started displaying the correct temperature--about 6C. The 22C number must come from the MOPA controller. We thus tentatively narrowed down the possible space of problems to: broken MOPA controller and/or clog in the cooling line going to the power amplifier. We decided to leave the MOPA off for the weekend, and start plumbing on Tuesday. It is of course possible that the controller is the problem, but we think leaving the laser off over the weekend is the best course of action.
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1620
|
Fri May 22 01:27:14 2009 |
pete | Update | SUS | 200 days of MC3 side |
Looks like something went nuts in late April. We have yet to try a hard reboot. |
Attachment 1: mc3_side_200days.png
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1619
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Fri May 22 00:43:24 2009 |
rob | Configuration | Computer Scripts / Programs | IFO configure scripts for XARM and YARM |
I edited the configure scripts (those called from the C1IFO_CONFIGURE screen) for restore XARM and YARM. These used to misalign the ITM of the unused arm, which is totally unnecessary here, as we have both POX and POY. They also used to turn off the drive to the unused ETM. I've commented out these lines, so now running the two restores in series will leave a state where both arms can be locked. This also means that the ITMs will never be deliberately mis-aligned by the restore scripts. |
1618
|
Thu May 21 18:21:57 2009 |
rana | Summary | Treasure | Yoichi's words |
Yoichi's final words on what do next with the interferometer (as of 5 PM on May 21, 2009):
- Measure laser noise couplings in spring and anti-spring configurations.
- Dewhitening filter turn on for the ETMs.
- Noisebudget - import from the sites.
- Stabilize CM handoff.
My personal sub-comments to these bullets:
- For the laser noise I'm not sure that we will be able to understand these if the couplings are mainly from junk light due to accidental HOM resonances.
- WE should look into putting a static passive stage of filtering into the ETMs if warranted by the NB.
- Because of the sad track record with this, I will start us off this time by importing and modifying the H1/L1 versions.
- I guess we can do this by just acquiring on MC2 with the huge CARM offset. It works for the single arm so it should work for offset CARM.
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1617
|
Thu May 21 18:07:32 2009 |
rana | Update | PSL | Screw on Needle valve loosened |
Alberto and I went in to loosen up the needle valve yesterday around 4:30 PM. The idea was to cut down on
the flow to the NPRO so that the cooling power of the chiller would be used almost entirely on the
amplifier instead of the NPRO block.
The need valve was basically all the way open. The lock nut was screwed in all the way and stuck. By using
pliers and a wrench for the nut, we freed the lock nut. Even so, the screw for the needle valve seemed to
be bad: I think the thread is stripped; it doesn't go down even after several turns. I even tried to squirt
alchohol on it and really press down in the hopes of catching a thread. It may have closed slightly but its
impossible to be sure.
I also increased the NPRO diode current to the max (+0.1 A). This got us a little bit of NPRO power and
I hope some more AMPMON stability. The attached plot shows 4 days of minute trend. If you squint you
might believe that we got some suppression in the HTEMP fluctuations over the last two days. |
Attachment 1: Untitled.png
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1616
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Thu May 21 18:05:03 2009 |
pete | Update | SUS | ETMX coils look OK |
Quote: |
I checked the four rear coils on ETMX by exciting XXCOIL_EXC channel in DTT with amplitude 1000@ 500 Hz and observing the oplev PERROR and YERROR channels. Each coil showed a clear signal in PERROR, about 2e-6 cts. Anyway, the coils passed this test.
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I also made xfer fctns of the 4 piston coils on ETMY and ETMX with OL_PIT. (I looked at all 4 even though the attached plot only shows three.) So it looks ike the coils are OK. |
Attachment 1: etmx_etmy_coils.pdf
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1615
|
Thu May 21 12:58:32 2009 |
rob | Configuration | ALARM | PEM count-half disabled |
I've disabled the alarm for PEM_count_half, using the mask in the 40m.alhConfig file. We can't do anything about it, and it's just annoying. |
1614
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Wed May 20 16:03:52 2009 |
steve | Omnistructure | Environment | using OSEMs to look at seismic activity |
Rana suggested using OSEM sensing voltages as guide lines to look seismic activity.
As you see todays drilling and tumping activity was nothing compared to the EQ of mag 5 and 4
Optic level servos are turned back on.
What Steve means is that there is some drilling going on in the CES shop to accomodate the new water flume group. We want to
make sure that the mirrors don't move enough to break the magnets. On the dataviewer we should look to make sure that the
sensor channels stay between 0-2 V. -Rana
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Attachment 1: eqOSEM5m4.jpg
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1613
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Wed May 20 10:43:17 2009 |
steve | Omnistructure | Environment | accelerometers sensitivity |
Quote: |
2009 May 18 03:39:36 UTC
Earthquake Details
Magnitude |
5.0 |
Date-Time |
- Monday, May 18, 2009 at 03:39:36 UTC
- Sunday, May 17, 2009 at 08:39:36 PM at epicenter
|
Location |
33.940°N, 118.338°W |
Depth |
13.5 km (8.4 miles) |
Region |
GREATER LOS ANGELES AREA, CALIFORNIA |
Distances |
- 2 km (1 miles) E (91°) from Lennox, CA
- 2 km (1 miles) SSE (159°) from Inglewood, CA
- 3 km (2 miles) NNE (22°) from Hawthorne, CA
- 7 km (4 miles) ENE (72°) from El Segundo, CA
- 15 km (10 miles) SSW (213°) from Los Angeles Civic Center, CA
|
Location Uncertainty |
horizontal +/- 0.4 km (0.2 miles); depth +/- 0.9 km (0.6 miles) |
Parameters |
Nph=139, Dmin=7 km, Rmss=0.42 sec, Gp= 40°,
M-type=local magnitude (ML), Version=C |
Source |
|
Event ID |
ci10410337 |
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Wilcoxon 731A seismic accelerometers and Guralp CMG-40T-old seismometer at magnitude 5 and 4 erthquakes |
Attachment 1: eq5m4.jpg
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1612
|
Wed May 20 09:55:18 2009 |
steve | Update | PEM | oplev servos turned off |
All oplevs servos turned off to protect our suspentions from vibration due to drilling and pounding in CES high bay area.
This activity will be done from 10 am till 3 pm today.
Meanwhile our IFO-air conditions are turned off for maintenance.
Their performance of 6 months is shown on plot. |
Attachment 1: ACpart6m.jpg
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1611
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Wed May 20 01:53:48 2009 |
rob, pete | Update | Locking | violin mode filters in drstep_bang |
Recently the watch script was having difficulty grabbing a lock for more than a few seconds. Rob discovered that the violin notch filters which were activated in the script were causing the instability. We're not sure why yet. The script seems significantly more stable with that step commented out. |
1610
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Wed May 20 01:41:19 2009 |
pete | Update | VAC | cryopump probably not it |
I found some neat signal analysis software for my mac (http://www.faberacoustical.com/products/), and took a spectrum of the ambient noise coming from the cryopump. The two main noise peaks from that bad boy were nowhere near 3.7 kHz. |
1609
|
Tue May 19 16:18:45 2009 |
steve | Configuration | VAC | IFO pressure is 4.2e-7 Torr with CRYO pump |
Quote: | Morning Vacuum condition: IFO is not being pumped, P1 pressure is 1.8 mTorr and rising (see P1 pressure plot of 100 min ).
Overnight the RGA protection software interlock at closed the VM1 valve triggering on CC1 = 1e-5 torr.
This interlock blocked our attempt to hold the IFO operational pressure in the high 1e-5 Torr range with one small
"beer can" turbopump (Varian V70D drag-turbo pumping speed for N2 is ~60 l/s at 75KRPM).
I started CRYO regeneration using TP3. Pressure readout on the P3 gauge. This is after 30 days of CRYO operation.
V5 was closed for 60 sec to see the outgassing rate of the cryopump surfaces. It was good (but I am not going to elog
what 'good' actually means - instead I will write it in my paper logbook to prevent others from learning). I will now'
go start cooling down the cryo pump.
** translated into English by Rana |
The Cryo cooled down to ~12K by noon.Photo switch was reset and VC1 was opened at 2pm
The VACMONITOR.adl screen is not working. Someone made some improvement on it last night. |
1608
|
Tue May 19 16:08:03 2009 |
rana | Summary | SEI | EUCLID |
From Stuart Aston, I've attached a picture of the EUCLID position sensor: |
Attachment 1: Picture_6.png
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1607
|
Tue May 19 15:57:07 2009 |
steve | Update | IOO | MC2 damping restored after EQ |
Earthquake mag 4.0 at Lennox, Ca trips MC2 watchdogs http://quake.usgs.gov/recenteqs/Quakes/ci10411545.html
See 40m accelerometers as they see it. |
Attachment 1: acc.jpg
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1606
|
Tue May 19 15:54:29 2009 |
Jenne | Update | PEM | More Plots for the S5 H1:DARM Wiener Filtering.... |
Even more plots for the Wiener filtering!
We have a set of spectrograms, which show (in color) the amplitude spectrum, at various times during a one month stretch of time, during S5. Each vertical data-'stripe' is 10min long.
We also have a set of band-limited plots, which take the spectra at each time, and integrate under it, for different frequency bands.
Each set of plots has the following 3 plots: The raw DARM spectrum, a ratio of residual/raw, and the residuals, normalized to the first one (on which the wiener filter was trained).
The residuals are the DARM spectrum, after subtracting the Wiener-filtered seismometer witness data.
From the ratio plots, it looks like the wiener filter is pretty much equally effective at the time on which the filter was trained, as one month later. Static filters may be okey-dokey for a long period of time with for the seismic stuff. |
Attachment 1: H1darmCompSpecgramRAW.png
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Attachment 2: H1darmCompSpecgramRATIO.png
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Attachment 3: H1darmCompSpecgramRESIDUALS.png
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Attachment 4: H1darmCompWienerRAW.png
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Attachment 5: H1darmCompWienerRATIO.png
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Attachment 6: H1darmCompWienerRESIDUALS.png
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1605
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Tue May 19 12:30:41 2009 |
rob | Configuration | SUS | ETMY f2pRatio script run |
Quote: | Now that the ETMY optical lever is not so bad, I ran the f2pRatio script and it seems to have worked.
I cleaned up the script a little also. Updated in the SVN.
ETMY's A2L scripts have to be run to reduce the A2L noise once the arm is locked again. Might also need
to set the OL UGF too. |
Just to show, in part, what the script does.
The F2A filters are turned on at 12:21, and the oplev no longer responds to large LSC drives in ETMY. |
Attachment 1: f2ademo.png
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1604
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Tue May 19 09:34:29 2009 |
steve | Configuration | VAC | IFO is not pumped & CRYO is being regenerated |
Morning Vacuum condition: IFO is not being pumped, P1 pressure is 1.8 mTorr and rising (see P1 pressure plot of 100 min ).
Overnight the RGA protection software interlock at closed the VM1 valve triggering on CC1 = 1e-5 torr.
This interlock blocked our attempt to hold the IFO operational pressure in the high 1e-5 Torr range with one small
"beer can" turbopump (Varian V70D drag-turbo pumping speed for N2 is ~60 l/s at 75KRPM).
I started CRYO regeneration using TP3. Pressure readout on the P3 gauge. This is after 30 days of CRYO operation.
V5 was closed for 60 sec to see the outgassing rate of the cryopump surfaces. It was good (but I am not going to elog
what 'good' actually means - instead I will write it in my paper logbook to prevent others from learning). I will now'
go start cooling down the cryo pump.
** translated into English by Rana |
Attachment 1: cryoreg.jpg
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Attachment 2: cryo30d.jpg
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1603
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Mon May 18 21:34:18 2009 |
rana | Configuration | SUS | ETMY f2pRatio script run |
Now that the ETMY optical lever is not so bad, I ran the f2pRatio script and it seems to have worked.
I cleaned up the script a little also. Updated in the SVN.
ETMY's A2L scripts have to be run to reduce the A2L noise once the arm is locked again. Might also need
to set the OL UGF too. |
1602
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Mon May 18 20:16:20 2009 |
rana | Configuration | VAC | not it |
There was essentially no change in the ETMY oplev spectrum with the cryo off!
So I went out to the ETMY OL table to see what else was going on. I found there one of
the most horrible opto-mechanical setups I have ever seen (and remember that I have once
seen someone mount an NPRO on a cardboard box). Some bad person had mounted the ETMY OL
lens on a 12" long skinny post and extended it towards the viewport. So there was a post
holder on the table and a lens ~12" away on a rickety lever arm.
I took this lens away and the spectrum is now good. Shame on you.
CYAN - cryo ON
BLACK - cryo OFF
BLUE - no crappy lens + mount
This OL needs to be fixed correctly by putting in a proper lens to get a small spot on the QPD. |
Attachment 1: a.png
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1601
|
Mon May 18 19:44:52 2009 |
rana, steve | Configuration | VAC | Cryo Pump turned off and valved off: 1 beer can only |
I was seeing some excess noise in the ETMY oplev yaw and so we turned off the cryo and restarted c1vac2 to get the turbo pump channels back.
The RGA was also turned off to protect its innocence and we are now running on the single beer can Turbo (TP3). The pressure has risen
from 1e-7 to 2e-5 torr. We'll probably level off at 5e-5 overnight and that's fine for now.
Unfortunately, the VM1 valve, which is between the RGA and the main volume, keeps getting turned off by our interlock software
to protect the RGA. Probably because our Vac screen shows the RGA 'Normal' even though the power is off and the record is invalid (white;
although the MEDM screen doesn't show it white).
I also moved Steve's secret Vacuum control screen from the target/ directory to the correct medm directory (with all the other Vacuum
screens) and added it to the SVN. |
1600
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Mon May 18 15:31:11 2009 |
rana | Update | PEM | Temp sensor |
Quote: | Picture of cooler for posterity is attached |
I'm puzzled as to why the minute trend doesn't pick this up; its clearly there in the full data.
Looks like its several samples too. Can someone please reboot this DCU and see if the problem goes away? |
Attachment 1: Untitled.png
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1599
|
Mon May 18 10:06:56 2009 |
caryn | Update | PEM | Temp sensor |
Quote: | To see if Caryn's data dropouts were happening, I looked at a trend of all of our temperature channels. Looks OK now.
Although you can't see it because I zoomed in, there's a ~24 hour relaxation happening before Caryn's sensors equilibrate.
I guess that's the insulating action of the cooler? We need a picture of the cooler in the elog for posterity.[/quote
Dropouts can't been seen with a minute trend, only a second trend. No big deal, but they are still occurring. See plot below.
The 24hr relaxation period is due to the cooler and some metal blocks that were cooled in the freezer and then put in the cooler to see if the relationship between the temp sensors changed with temperature. The relationship is not linear, which probably means there is some non-linearity in each temperature sensor's relationship to temperature. So, when calibrating them with Bob's temp sensor, more than 2 data points need to be collected.
Picture of cooler for posterity is attached |
Attachment 1: datadropout.png
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Attachment 2: coolerpic1.jpg
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Attachment 3: coolerpic2.jpg
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1598
|
Mon May 18 02:18:17 2009 |
rana | Summary | SEI | Using STACIS w/ a good position sensor | WE turned off STACIS a few years ago because we noticed that it was causing noise below a few Hz and making
the overall velocity between the ends higher than with them off. I'm pretty sure they were causing noise
because they use little geophones which are noisy. Below ~0.2 Hz the horizontal geophones are also probably
limited by tilt-horizontal coupling.
Another concept (based on discussion with Brian Lantz and Matt Evans) is to instead put a good position sensor
between the ground and then blue support beam. Since the the STACIS rubber acts like a Q~2 passive resonance at
20 Hz, the whole seismic system (including the blue beams, in-vac tubes, and internal stack) act like a proof
mass of a seismometer.
So, in principle, if we use a very good position sensor and feedback to the STACIS piezo actuators, we can cancel
the ground motion before it enters the stacks. The initial LIGO OSEMs have a noise of 10^-10 m/rHz above 10 Hz
and going up like 1/f below 10 Hz. The AdvLIGO BOSEMs have a noise of ~2x better. Even better, however, are the
UK's EUCLID interferometric OSEMs (developed by Stuart Aston and Clive Speake).
In the attached plot, I show what we can get if we use these EUCLIDs make a ~60 Hz BW feedback loop w/ STACIS.
BLACK - raw ground motion measured by the Guralp
MAGENTA - motion after passive STACIS (20 Hz harmonic oscillator with a Q~2)
GREEN - difference between ground and top of STACIS
YELLOW - EUCLID noise in air
BLUE - STACIS top motion with loop on (60 Hz UGF, 1/f^2 below 30 Hz)
CYAN - same as BLUE, w/ 10x lower noise sensor
One of the SURF projects this summer is to put together a couple different sensors like EUCLID to understand the noise. |
Attachment 1: stacis40.png
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1597
|
Mon May 18 01:54:35 2009 |
rana | Update | PEM | Unplugged Guralp channels | To see if Caryn's data dropouts were happening, I looked at a trend of all of our temperature channels. Looks OK now.
Although you can't see it because I zoomed in, there's a ~24 hour relaxation happening before Caryn's sensors equilibrate.
I guess that's the insulating action of the cooler? We need a picture of the cooler in the elog for posterity. |
Attachment 1: Untitled.png
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1596
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Sun May 17 23:22:19 2009 |
rana | Update | Environment | seisBLRMS for the past 3 weeks | Looks like Chris Wipf's fix of using fclose worked for the NDS client.
The attached plot shows the minute trend RMS - we should put the calibration for these into the .m file
so that the EPICS values are in something useful like microns or microns/sec.
I also now see why Nodus seems really slow with the elog sometimes. When we load a page with an attached
PDF, it runs 'gs' to try to generate the PNG preview. Because its on Solaris it often fails because it
can't find some font. We should probably disable the preview or fix the font issue. |
Attachment 1: Untitled.png
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1595
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Sun May 17 21:45:40 2009 |
rob | Update | ASC | ITMX oplev centered | |
1594
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Sun May 17 20:50:38 2009 |
rob | Omnistructure | Environment | mag 5.0 earthquake in inglewood | 2009 May 18 03:39:36 UTC
Earthquake Details
Magnitude |
5.0 |
Date-Time |
- Monday, May 18, 2009 at 03:39:36 UTC
- Sunday, May 17, 2009 at 08:39:36 PM at epicenter
|
Location |
33.940°N, 118.338°W |
Depth |
13.5 km (8.4 miles) |
Region |
GREATER LOS ANGELES AREA, CALIFORNIA |
Distances |
- 2 km (1 miles) E (91°) from Lennox, CA
- 2 km (1 miles) SSE (159°) from Inglewood, CA
- 3 km (2 miles) NNE (22°) from Hawthorne, CA
- 7 km (4 miles) ENE (72°) from El Segundo, CA
- 15 km (10 miles) SSW (213°) from Los Angeles Civic Center, CA
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Location Uncertainty |
horizontal +/- 0.4 km (0.2 miles); depth +/- 0.9 km (0.6 miles) |
Parameters |
Nph=139, Dmin=7 km, Rmss=0.42 sec, Gp= 40°,
M-type=local magnitude (ML), Version=C |
Source |
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Event ID |
ci10410337 |
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1593
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Sun May 17 14:35:52 2009 |
Yoichi | Update | VAC | VC1 opened | I found the VC1 was closed and the pressure was 4.5e-3 torr.
I tweaked the optical sensor (cryopump temperature), and opened VC1. |
1592
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Sat May 16 16:20:33 2009 |
rob | Update | LSC | arms, coils, locks, #2 |
Quote: |
This is the two arms locked, for an hour. No integrator in either loop, but from this it looks like ETMY may have a bigger length2angle problem than ETMX. I'll put some true integrators in the loops and do this again.
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There appear to be at least two independent problems: the coil balancing for ETMY is bad, and something about ITMX is broken (maybe a coil driver).
The Y-arm becomes significantly misaligned during long locks, causing the arm power to drop. This misalignment tracks directly with the DC drive on ETMY. Power returns to the maximum after breaking and re-establishing lock.
ITMX alignment wanders around sporadically, as indicated by the oplevs and the X-arm transmitted power. Power returns to previous value (not max) after breaking and re-establishing lock.
Both loops have integrators. |
Attachment 1: twoproblems.png
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Attachment 2: coil_imbalanceETMY.png
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Attachment 3: ITMXalignment.png
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1591
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Fri May 15 17:30:00 2009 |
rob | Update | LSC | arms, coils, locks | This is the two arms locked, for an hour. No integrator in either loop, but from this it looks like ETMY may have a bigger length2angle problem than ETMX. I'll put some true integrators in the loops and do this again.
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Attachment 1: armslock_no_int.png
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1590
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Fri May 15 16:47:44 2009 |
josephb | Update | Cameras | Improved camera code | At Rob's request I've added the following features to the camera code.
The camera server, which can be started on Ottavia by just typing pserv1 (for camera 1) or pserv2 (for camera 2), now has the ability to save individual jpeg snap shots, as well as taking a jpeg image every X seconds, as defined by the user.
The first text box is for the file name (i.e. ./default.jpg will save the file to the local directory and call it default.jpg). If the camera is running (i.e. you've pressed start), prsessing "Take Snapshot to" will take an image immediately and save it. If the camera is not running, it will take an image as soon as you do start it.
If you press "Start image capture every X seconds", it will do exactly that. The file name is the same as for the first button, but it appends a time stamp to the end of the file.
There is also a viedo recording client now. This is access by typing "pcam1-mov" or "pcam2-mov". The text box is for setting the file name. It is currently using the open source Theora encoder and Ogg format (.ogm). Totem is capable of reading this format (and I also believe vlc). This can be run on any of the Linux machines.
The viewing client is still accessed by "pcam1" or "pcam2".
I'll try rolling out these updates to the sites on Monday.
The configuration files for camera 1 and camera 2 can be found by typing in camera (which is aliased to cd /cvs/cds/caltech/apps/linux64/python/pcamera) and are called pcam1.ini, pcam2.ini, etc.
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1589
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Fri May 15 14:05:14 2009 |
Dmass | HowTo | Computers | How To: Crash the Elog | The Elog started crashing last night. It turns out I was the culprit, and whenever I tried to upload a certain 500kb .png picture, it would die. It has happened both when choosing "upload" of a picture, and when choosing "submit" after successfully uploading a picture. Both culprits were ~500kb .png files. |
1588
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Fri May 15 00:02:34 2009 |
pete | Update | SUS | ETMX coils look OK | I checked the four rear coils on ETMX by exciting XXCOIL_EXC channel in DTT with amplitude 1000@ 500 Hz and observing the oplev PERROR and YERROR channels. Each coil showed a clear signal in PERROR, about 2e-6 cts. Anyway, the coils passed this test.
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1587
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Thu May 14 16:07:20 2009 |
pete | Summary | SUS | Channel Hopping: That ancient enemy (MC problems) |
Quote: |
Quote: | The MC side problem could also be the side tramp unit problem. Set the tramp to 0 and see if that helps. |
This started around April 23, around the time that TP1 failed and we switched to the cryopump, and also when there was a mag 4 earthquake in LA. My money's on the EQ. But I don't know how. |
I wonder if this is still a problem. It has been quiet for a day now. I've attached a day-long trend. Let's see what happens. |
Attachment 1: mc3_5days.jpg
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1586
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Thu May 14 15:28:28 2009 |
steve | Summary | SUS | April 24 earthquake effect on MC2 |
Quote: |
Quote: | The MC side problem could also be the side tramp unit problem. Set the tramp to 0 and see if that helps. |
This started around April 23, around the time that TP1 failed and we switched to the cryopump, and also when there was a mag 4 earthquake in LA. My money's on the EQ. But I don't know how. |
Only MC2 moved in this earth quake. Was the MC alignment touched up since than?
Have you guys swapped satellite amp of MC3 yet? |
Attachment 1: eq042409.jpg
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1585
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Thu May 14 02:36:05 2009 |
pete | Update | Locking | unstable IFO | It seems that the MC3 problem is intermittent (one-day trend attached). I tried to take advantage of a "clean MC3" night, but the watch script would usually fail at the transition to DC CARM and DARM. It got past this twice and then failed later, during powering up. I need to check the handoff.
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Attachment 1: mc3.jpg
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