Displaying reports 66201-66220 of 83192.Go to page Start 3307 3308 3309 3310 3311 3312 3313 3314 3315 End
Reports until 08:50, Wednesday 25 March 2015
H1 CDS (DAQ)
david.barker@LIGO.ORG - posted 08:50, Wednesday 25 March 2015 (17453)
CDS model and DAQ restart report, Tuesday 24th March 2015

model restarts logged for Tue 24/Mar/2015
2015_03_24 10:15 h1asc
2015_03_24 12:22 h1sushtts

2015_03_24 12:44 h1broadcast0
2015_03_24 12:44 h1dc0
2015_03_24 12:44 h1fw0
2015_03_24 12:44 h1fw1
2015_03_24 12:44 h1nds0
2015_03_24 12:44 h1nds1

no unexpected restarts. Maintenance day: asc and sushtts cleanup, Beckhoff changes, associated DAQ restart.

H1 DetChar (ISC)
laura.nuttall@LIGO.ORG - posted 08:49, Wednesday 25 March 2015 - last comment - 10:10, Thursday 26 March 2015(17452)
Arches seen in DARM

Laura, Josh, Andy, Joe, Detchar

We took a look at the 28 Mpc lock on 24th March to see if there was any evidence of arches that we have seen previously at LLO (for example LLO alog 17090).

The first attachement shows a histogram of the rate of glitches (omicron triggers) binned by the value of IMC-F at the same time. The plot looks pretty Gaussian, except for a few bins specifically between IMC-F values of -37.5 to -41.7 and -45.8 and -50. Between these values we see evidence of arches in DARM. The second attachment is a pdf file showing the arches in DARM lining up with values of IMC-F in the second bin. Here are links to many spectograms confirming the arches in the IMC-F bins outlined (spectrograms for IMC-F bin -37.5 to -41.7 / spectrograms for IMC-F bin -45.8 to -50). Each spectrogram time corresponds to a glitch as seen by omicron.

LLO has dramatically reduced the effect of these arches, see LLO alog 17191.

Also the value IMC-F has when these arches appear in DARM seems to drift, i.e. there does not appear to be a specific value of IMC-F which produces the arches (this is evident in the second attachement). This is not what we have seen at LLO, does anyone know what could be causing this?

Images attached to this report
Non-image files attached to this report
Comments related to this report
andrew.lundgren@LIGO.ORG - 09:53, Wednesday 25 March 2015 (17457)
Andy, Laura, DMac

Here's a look at one of the whistles, and the putative cause as an RF beatnote with IMC-F. The idea is that the IMC VCO is beating against another (nearly) fixed RF oscillator, and that's what we see in DARM. In that case, the frequency track should look like the difference between IMC-F (calibrated in kHz) with some fixed value.

In fact, the whistle clearly seems to match half of the frequency difference (black trace) rather than the full difference (red trace). Perhaps this hints at the type of coupling? Here, the fixed value is about -46.9 kHz (relative to whatever IMC-F's reference is), but we think this drifts during the lock. We can look in detail at some more of these, and find out.
Images attached to this comment
daniel.sigg@LIGO.ORG - 11:47, Wednesday 25 March 2015 (17462)

Why not use the frequency readbacks of the oscillators and VCOs rather than the somewhat arbitrary IMC_F? The radbacks are only once per second, but they can still tell you which units are close in frequency.

andrew.lundgren@LIGO.ORG - 13:20, Wednesday 25 March 2015 (17463)
I'd be happy to look at the readbacks, as long as they are recorded and available offsite. Can tell me what the channel names are?
daniel.hoak@LIGO.ORG - 14:04, Wednesday 25 March 2015 (17465)

I put some notes about these channels in the summary of the ISC F2F last fall.  ("RF crosstalk" section)

The channel names and labels are in the attached code.  There, I look at the time around the event that Andy sent around to the DetChar mailing list yesterday.  It's not totally obvious what VCO is beating against the PSL VCO, the closest one is ALS COMM, but it's about 400kHz away at the time of the glitch.

The first plot shows the value of all the corner station VCOs in the ten minutes around the glitch, the second plot is a zoom around the PSL VCO frequency.

Non-image files attached to this comment
andrew.lundgren@LIGO.ORG - 10:10, Thursday 26 March 2015 (17485)
It seems like H1:SYS-TIMING_C_FO_A_PORT_11_SLAVE_CFC_FREQUENCY_5, which Dan has labeled as the PSL readback, is the best candidate. This seems to be roughly equal to (1/2)*IMC-F + 79.225 MHz, delayed by one second (i.e. I can line those two things up and they overlap). Is the one second delay due to some loop or is it just a quirk of the recording system?

The whistles occur whenever this readback crosses 79.2 MHz, which is the fixed fiber AOM frequency from the talk referenced in Dan's notes from above.
H1 ISC
eleanor.king@LIGO.ORG - posted 03:15, Wednesday 25 March 2015 (17451)
SRC length measurement

Kiwamu, Dan, Daniel, Elli

Today we locked SRMI using H1:LSC-REFLAIR_A_RF45_I_MON for SRCL and H1:LSC-ASAIR_A_RF45_Q_MON for MICH. This configuration is more stable than previous locks where we were locking MICH to ASAIR_A_LF and it was clearer where the locking point is.  We retook transfer function of AUX laser and carrier beatnote at OMC_REFL path against AUX laser offfset with and without beam clipping.  MICH offset was 20 counts of normalised H1:LSC-ASAIR_A_RF45_Q_MON so we were locked very close to the MICH dark fringe.  The raw data is available in /ligo/home/controls/elli.king/SRClengthdata.

I have unlocked SRMI and I am leaving the guardians in the down state.  We changed the whitening gain on REFL_A_RF45 for the measurement but I have set it back to zero and have reset the dark offsets H1:LSC-REFLAIR_A_RF45_I_OFFSET H1:LSC-REFLAIR_A_RF45_Q_OFFSET to tTuesday morning's values.

H1 ISC (ISC, PSL)
evan.hall@LIGO.ORG - posted 01:47, Wednesday 25 March 2015 - last comment - 09:23, Wednesday 25 March 2015(17435)
A look at intensity noise coupling into DARM

Kiwamu, Lisa, Sheila, Dan, Evan

Summary

A preliminary measurement shows that we are not quite limited by intensity noise between 50 Hz and 1 kHz, but we need to take another round of measurements in order to say anything conclusive.

This was taken before switching to the ETMY ESD and before feedforward subtraction of MICH.

This result is roughly consistent with Gabriele's conclusion that the intensity noise coupling above 100 Hz is a factor of a few below the total DARM noise.

Details

Kiwamu wired up the extra LSC DAC channel (LSC-EXTRA_AO_2) to drive the excitation point of the ISS second loop (PSL-ISS_TRANSFER2_INJ).

Then we drove a swept sine using this DAC channel and looked at the transfer function IMC-IM4_TRANS_SUMLSC-DARM_IN1. The data aren't great, since it seems hard to get good coherence around 120 Hz and below 50 Hz. I've attached a calibrated version of the transfer function. IM4 trans is nominally calibrated into microwatts, and the conversion to DARM_IN1 from OMC-DCPD_SUM for this lock is 5.4×10−7 ct/mA (the DCPD_SUM channel is nominally calibrated into milliamps). The transfer function looks very feature-rich, and we would greatly benefit from a more careful measurement.

A good time to look at IM4 during this lock configuration is 2015-03-24 05:08:20 to 05:10:20 UTC. Using the ASD of the IM4 sum power during this time, one can use the above TF to propagate it forward to DCPD sum photocurrent. This can be propagated foward to DARM noise using the coefficient 4.6×10−13 m/mA. I've undone the DARM pole, but not the DARM loop (since our measurement is more or less above the loop UGF).

Non-image files attached to this report
Comments related to this report
gabriele.vajente@LIGO.ORG - 09:23, Wednesday 25 March 2015 (17455)ISC

Few months ago I did some simulations to understand the large coupling of intensity noise at Livingston. Details are in LLO alog 13768, 13963, 1398514091 and 14188.

At Livinston the dominant cause of increased coupling was the mismatch of the lenses in the two ITMs. At LHO the shape of the coupling seems different. It is very similar to the simulation result I got with a MICH offset, see the linked alog entry and the attached plot.

Images attached to this comment
H1 ISC
evan.hall@LIGO.ORG - posted 21:50, Tuesday 24 March 2015 - last comment - 00:03, Wednesday 25 March 2015(17447)
Residual DARM motion

Lisa, Evan

Attached is a spectrum of the suppressed DARM error signal from last night. The RMS is about 3×10−13 m down to 0.1 Hz, and (as we've already seen) almost all of it comes from motion between 1 and 5 Hz. By looking at the recent DARM OLTF for H1 (LHO#17153), we see that we easily have more room for a boost below 10 Hz or so (and Dan is already working on this).

Also attached are spectra of recent "best" locks from H1 and L1, along with the GWINC prediction for 10 W of input power.

 

P.S.: The rms traces of the calibrated DARM signals in DTT appear to be completely bogus. The attached plot was done independently in python.

P.P.S.: Attempting to print these spectra in pdf, eps, or ps causes DTT to crash.

Images attached to this report
Non-image files attached to this report
Comments related to this report
lisa.barsotti@LIGO.ORG - 21:53, Tuesday 24 March 2015 (17448)ISC
Some plots with the best L1 and H1 sensitivity curves so far.
Non-image files attached to this comment
daniel.hoak@LIGO.ORG - 00:03, Wednesday 25 March 2015 (17450)

The attached image describes the effect of the boost filter we'd like to add to DARM.  The blue trace is the current set of DARM integrators, boosts, RGs, and so on (I haven't included the suscomp filter).  The red trace has the new boost in FM7.  The blue trace is the same as the comparison that Peter made between H1 and L1 back in February.  Compare the red trace in the attached plot (the change we'd like to make) to the L1 trace in his comparison; this boost will bring us more in line with the Livingston loop shape.  (The changes made two weeks ago to the DARM loop were made to the suscomp filter.)

The boost adds 20dB of gain at 3Hz, takes away ~1.5dB at 10Hz due to a pair of complex zeroes, and loses about 4deg of phase at 50Hz.  The last DARM OLTF we measured says we have 45deg of phase margin at the 50Hz UGF, and probably about 30dB of gain at 3Hz, so this filter should significantly improve the suppression in the 2-5Hz band without costing too much phase.

We might want to add an RG filter at 0.45Hz to suppress the pendulum resonance, too.  Or increase the existing RG in FM3.

Images attached to this comment
H1 ISC
sheila.dwyer@LIGO.ORG - posted 20:26, Tuesday 24 March 2015 (17446)
last night's lock

Dan, Sheila

We had a quick look at last night's lock, it seems that the degradation in the range over time was not due to an alingment drift, since we can see that the build ups stayed high durring the lock.  It seems like the wind picking up again this morning was pretty well correlated with the range decreasing.  We don't know how to get DMT sensmon data (or any DMT data) from the control room. Dan made this plot by logging into the cluster to find the DMT sensmon frame files.  

Non-image files attached to this report
H1 CDS
sheila.dwyer@LIGO.ORG - posted 19:16, Tuesday 24 March 2015 - last comment - 21:05, Friday 27 March 2015(17445)
timing difference between beckhoff and RCG channels?

Dan, Sheila

The attached screenshot shows a one second trend of the beckhoff channel that is the fast shutter trigger readback, along with two RCG channels, the first is AS_C sum, this PD should be the source for the fast shutter trigger, and ASAIR_LF,  which should see similar power fluctuations.  

The beckhoff channel seems to be 0.2 seconds ahead of the RCG channels.  This timing difference sometimes makes it appear as though the fastshutter shut first, causing the lockloss, as in the second attached screenshot. 

We would like to prove definteively that the shutter is only shutting when it should, but we don't have a readback that we trust.  

Images attached to this report
Comments related to this report
daniel.sigg@LIGO.ORG - 21:05, Friday 27 March 2015 (17549)

Dave and I looked into this somewhat and we don't think that the timestamps of the EtherCAT systems are used at all by the frame builder. As a matter of fact the internal clock of these machines was about 3 seconds off. Since it is hard to believe that the EtherCAT systems violate causality, the most likely candidates are frame builder, data concentrator or maybe the EPICS gateway. This would also mean that all data transported through EPICS to the frame builder could be affected. More investigations are pending.

H1 SEI
jim.warner@LIGO.ORG - posted 17:36, Tuesday 24 March 2015 (17444)
More BSC blend filter ellipses

Following up on my log 17295, the 10 hz CPS low pass elliptical filter is now running on all BSC ISI's. I've spent today working on ETMX trying to push the St2 filter down more and adding a similar filter to St1 but it's not ready for show time, so only the "old" filter mod is running.

First attached plot shows the X and Y St2 sensors, X is red ( gnd STS, St2 CPS& GS13), Y is blue, Y is running the "old" elliptical filter, X is running the more aggressive setup. You can see that from ~2 to 15 hz the more aggressive (red) setup does better. Unfortunately, the St1 elliptical filter interferes with the sensor correction (changing the phase of the CPS plant), so the ground STS signal doesn't cancel the CPS signal as well, increasing motion by ~2x at ~.5 hz. Or maybe the ground is a little worse, idk. I plan on tuning this a little more, maybe modifying the sensor correction as well (when I understand it better), and will try again when the opportunity presents itself.

The next two plots show changes I've made to the blends. Second plot is St1, red is stock, green is the filter I tried today(with problems at .5 hz), blue is what I will try next.

Third plot is St2 blends, red(not installed) is new, blue is the only thing running right now.

Images attached to this report
H1 CDS (DAQ)
david.barker@LIGO.ORG - posted 17:11, Tuesday 24 March 2015 (17443)
CDS model and DAQ restart report, Monday 23rd March 2015

model restarts logged for Mon 23/Mar/2015

no restarts reported

H1 CDS (DAQ)
david.barker@LIGO.ORG - posted 17:10, Tuesday 24 March 2015 - last comment - 09:14, Thursday 26 March 2015(17442)
CDS Maintenance Summary

Time Code Translator work at end stations, WP5116

Dave, Jim:

We racked up the missing TCT in EY, then connected it to one of the unused fiber pairs running between the VEA rack and the computer rack. We verified it was using ports 19 and 20 in the MSR (same as EX). Once connected the TCT synced to the time and the error LED on the MSR sender was extinguished.

We then ran 30 foot 50-Ohm coax, BNC terminated, between the TCT in the computer rack, through the wall, to the first port on the CER comparator. This was done at both EX and EY. The 1PPS port on the back of the TCT is a TNC connector, so we used a TNC-BNC adapter on that port for EX. We need to do the same for EY.

At EX, the comparator is now displaying a time of -22.2uS on the TCT port, roughly the time of flight between the buildings. We will revisit the TCT internal settings, they are most probably what was left from iLIGO.

Rebuild of ASC model

Daniel, Dave:

Daniel though h1asc would benefit from a clean build, install and restart. This was done, I'll see if this helped in the IPC errors.

PCAL filter modules, port from PEM file

Sudarshan, Dave:

Sudarshan discovered that I had forgotten to migrate the PCAL filters from when the CAL system shared a core with the PEM. He copied them from H1PEME[X,Y].txt to H1CALE[X,Y].txt, making a CAL_PCAL to PCAL name change in the process. The filters were then loaded into the PCAL models at both end stations.

Comments related to this report
james.batch@LIGO.ORG - 09:14, Thursday 26 March 2015 (17481)
The TNC to BNC adapter has been installed to connect the EY TCT to the timing comparator.  Remaining work is calibration of the CsIII frequency standard, the time distribution system in the corner stations, and the TCT at the end stations.
LHO VE (VE)
gerardo.moreno@LIGO.ORG - posted 16:53, Tuesday 24 March 2015 (17441)
Pump Carts by HAM1 and HAM2 are Off

(Kyle, Gerardo)
Turned off and decoupled two pump carts, from HAM1 and HAM2 annulus system.
The annulus ion pump for HAM1 still not connected to CDS, HAM2 is.

LHO VE
bubba.gateley@LIGO.ORG - posted 16:16, Tuesday 24 March 2015 (17439)
Beam Tube Washing
Scott L. Ed P. Chris S. Joe D.

Completed tube cleaning to single door between X-1-6 and X-1-7, 40 meters today. Test results for cleaned section and next dirty section are posted here.
Installed 70 support tube caps on previously cleaned sections and more on order. 
Continuous monitoring of beam tube pressures by control room operator during cleaning operations. 
Non-image files attached to this report
H1 ISC
daniel.sigg@LIGO.ORG - posted 16:10, Tuesday 24 March 2015 - last comment - 22:57, Wednesday 25 March 2015(17438)
Fiber AOM

Since we are frequently running out of range on the end station VCOs, when there is high wind, we switched the drive of the fiber AOM back to the IMC VCO. This was the original scheme. It has the disadvantage that the end station green locking now depends on the IMC to be locked. On the other hand, this is probably not a big deal, when working with the fully locked interferometer.

Images attached to this report
Comments related to this report
sheila.dwyer@LIGO.ORG - 22:57, Wednesday 25 March 2015 (17476)

Kiwamu, Sheila, 

We found that we had to lock ALS DIFF and COMM sequentially with this change, instead of in parallel as we have been doing.  This morning we found that we could not transition the tidal to common with this change, so we reverted it so we are again using the fixed frequency RF source for the fiber AOM.  We labeled both of the cables as well, so that next time the wind picks up we can put this back.  We will probably not need high bandwidth common tidal with this modification, so we can try turning this bandwidth down and leaving off the IMC F offset, then later engaging it with a slow ramp.  

H1 General
edmond.merilh@LIGO.ORG - posted 15:56, Tuesday 24 March 2015 (17416)
Daily Ops Summary

07:00 Cris and Karen into LVEA

08:08 IFO Fully locked at LOWNOISE_ESD_ETMY - ~18Mpc.

08:15 Gerardo into LVEA

08:25 Gerardo out of the LVEA

08:49 Joim installing new isolation filters on BS

08:49 Heintze out to LVEA -TCS

08:57 Gerardo out to LVEA - HAM1

09:08 Corey out to squeezer bay 

09:14 Ellie out to LVEA - HAM1 area

09:18 Betsy out to LVEA

09:21 Jim W and TJ to EX

09:30 Jim B to EY to install Time Code Translator.

09:21 Jim W and TJ back from EX

09:53 Gerardo out of LVEA - Fil and Andres are still in pulling RF cables around HAMS 3,4

10:00 Jodi and Gary out of the LVEA

10:23 D Barker and J Batch back out to EY

10:25 HFD on site

10:58 Doug Cook out to LVEA - running a box of parts out to a cabinet.

11:08 P King into H2 enclosure

11:15 D Barker restarting ASC

11:42 P King out of H2 enclosure

12:07 Matt outnof LVEA

12:08 Dave amd Jim back to EX

12:10 Fil and co. out of LVEA

12:38 Dave and Jim back from EX - DAQ restart imminent 

12:42 DAQ restart

12:56 Karen @ EY

13:43 Karen Leaving EY

14:50 Fill out to LVEA to make some  measurements for cables

15:00 Kyle and Gerardo to MidX

15:07 Fil out of LVEA

 

 

LHO VE
kyle.ryan@LIGO.ORG - posted 15:54, Tuesday 24 March 2015 (17437)
~1520 hrs. local -> accidentally "bumped" tilt meter resting on X-mid VEA floor west of X1 adapter spool


			
			
H1 AOS (AOS, IOO, ISC, SUS)
suresh.doravari@LIGO.ORG - posted 15:54, Tuesday 24 March 2015 (17436)
SR3 Oplev SUM signal characteristics : Oplev diode laser not yet fixed.

This is the analysis of a quiet stretch of data in SR3 oplev from yesterday. 

I checked to make sure of the following:

a) Alignment sliders have not been moved during this period 

b) There is no actuation to SR3 at this time. 

c) The signal levels on all SR3 quadrants are okay, that is the quadrants are not saturated. 

 

I am posting here screenshots of plots of:

1) the time series for 16 hrs at 1 sec sampling rate

2) the time series for a 2 hr stretch with 256 Hz sampling from within the 16hr stretch

3) a RIN spectrum of the SUM signal for the 16 hrs sample going down to 10^-3 Hz to 0.1 Hz

4) a RIN spectrum of the SUM signal for the 2 hrs sample going from 0.1 Hz to 100 Hz

5) A spectrogram of the 2 hrs signal showing the broadband noise injections due to the glitches in the laser.

 

Note:

All data for this analysis is available in /ligo/data/oplevs  at LHO. File name LHO_SR3_before_LD_Fix.mat

Images attached to this report
H1 General
edmond.merilh@LIGO.ORG - posted 08:12, Tuesday 24 March 2015 - last comment - 16:47, Tuesday 24 March 2015(17417)
IFO RELOCK at LOWNOISE_ESD_ETMY

08:08 IFO fully locked @ ~ 18Mpc  (according to SensMon).

Comments related to this report
edmond.merilh@LIGO.ORG - 08:42, Tuesday 24 March 2015 (17418)

Broke lock @ 08:41 :( Not bad for a maintenance day!

sheila.dwyer@LIGO.ORG - 16:47, Tuesday 24 March 2015 (17440)

It seems as though after dropping lock the IFO came back twice (on its own or with some help from Ed?), with one locking attempt that failed in locking DRMI_1F.  

The attached plots show the guardian state from 13:20 UTC to 16:20, the longest steps in the relocking process are still finding IR and locking DRMI, the long DRMI lock was about 8 minutes, the total time to recover from the lock loss was about 40 minutes (inlcuding the failed attempt), and the second time it took 15 minutes.  

I think we can say that we now have some "one click" locks, unless Ed had to intervene in some way to lock this.    

Images attached to this comment
H1 ISC (DetChar, ISC)
lisa.barsotti@LIGO.ORG - posted 02:28, Tuesday 24 March 2015 - last comment - 22:19, Tuesday 24 March 2015(17411)
ETMY low noise ESD, MICH feed-forward, ASC cut-offs, low noise coil drivers (started), 28 Mpc
Evan, Sheila, Dan, Kiwamu, Lisa 

SUMMARY 

The wind dropped below 20 mph in the evening, and we started locking. After some roll, bounce and violin damping, we made it to DC readout @ 8W. We successfully transitioned DARM to ETMY with low noise ESD and got some MICH feed-forward cancellation going. We improved the noise between 30-200 Hz, and reached  28 Mpc  (according to SensMon). 

The noise was more stationary than  previously observed . 

However,  the OMC is still shaking , and it is not good. Dan has a resonant gain for DARM ready to be tested to reduce the noise around 3 Hz, but we didn't manage to get that done tonight. 

We leave the interferometer locked at 28 Mpc starting at March 24, 2015 9:17 UTC . 


DARM control on ETMY with low noise ESD  

We did the transition from ETMX to ETMY L2 for DARM, but the interferometer was very glitchy, and we decided to abandon L2 control and try the new  Den's strategy  to do the feed-forward to ITM(Y) L2. 
Evan got about a factor of 10 subtraction (FM9 has BS plant inversion in LSC-MICHFF filter bank, gain +0.048). 

ASC cut-off filters 

Since none of the ASC loops had cut-offs, we decided to add  some . They are now engaged by the Guardian. A more fine tuning will happen at some point. 

Started switching coil driver to low noise  

We started switching the coil driver to  low noise . Evan will post a table later with the successful switches we did after acquiring the DRMI lock. We need to do more work on this, some failed.
Comments related to this report
evan.hall@LIGO.ORG - 02:35, Tuesday 24 March 2015 (17412)

Spectra attached.

Images attached to this comment
daniel.hoak@LIGO.ORG - 02:38, Tuesday 24 March 2015 (17413)

Here is a plot of the lingering coherences with LSC DOFs.

Images attached to this comment
gabriela.gonzalez@LIGO.ORG - 05:15, Tuesday 24 March 2015 (17414)
Very nice progress! 
albert.lazzarini@LIGO.ORG - 05:53, Tuesday 24 March 2015 (17415)
Excellent news. Great progress. 
thomas.massinger@LIGO.ORG - 09:48, Tuesday 24 March 2015 (17420)DetChar

This is fantastic progress, congratulations!

For anyone that would like to look at the data quality or run any DetChar tools on this data, the following GPS times can be used:

1111223896 - 1111239923

Duration: 16027 seconds

nergis.mavalvala@LIGO.ORG - 11:52, Tuesday 24 March 2015 (17426)
This entry should make Lisa a contender for her "best log entry" prize. Nice going, everyone!
evan.hall@LIGO.ORG - 22:19, Tuesday 24 March 2015 (17449)

These are the coil driver states that we've been using so far:

OLD PRM PR2 SRM SR2 PR3 SR3 BS
M1   1 1 1 1 1 1
M2   2 2 2 1 1 1
M3 2 2 2 1 1 2

 

OLD IX IY EX EY
R0 1 1 1 1
M0 1 1 1 1
L1 3 3 2 2
L2 2 1 1 1

Now we've managed to switch to the following configuration for acquisition (following the tables in LLO#16565):

ACQ PRM PR2 SRM SR2 PR3 SR3 BS
M1 2 2 1 2 2 2 1
M2 2 3 2 3 3 3 2
M3 2 2 2 2 2 2

 

ACQ IX IY EX EY
R0 1 2 1 1
M0 1 2 1 1
L1 3 4 2 2
L2 2 1 1 1
 

Green indicates a low-noise state, and red any other state. So far we have encountered the following things:

  • If any stage of the SRM is switched to a low-noise state, it will start to saturate. We are trying to figure out whether this is a problem with the LSC (which feeds back to M2 and M3) or the ASC (which feeds back to M1).
  • ITMX M0 appears to be miswired; changing the state request appears to affect the test/coil bits instead, resulting in an error. Jeff and Richard are looking into this.
Displaying reports 66201-66220 of 83192.Go to page Start 3307 3308 3309 3310 3311 3312 3313 3314 3315 End