The nds2-client software for Linux has been updated on the DAQ test stand to version 0.10.5 (which is listed as the current version on the LSC NDS2 Trac web page).
model restarts logged for Wed 10/Dec/2014
2014_12_10 12:13 h1iscey
2014_12_10 12:16 h1iscex
2014_12_10 12:20 h1iscex
2014_12_10 12:20 h1iscey
2014_12_10 12:24 h1broadcast0
2014_12_10 12:24 h1dc0
2014_12_10 12:24 h1fw0
2014_12_10 12:24 h1fw1
2014_12_10 12:24 h1nds0
2014_12_10 12:24 h1nds1
2014_12_10 16:48 h1iscey
no unexpected restarts. Continuation of code change for end station ISC (with associated DAQ restart). later h1iscey restart to track excitation problem. Conlog frequently changing channels list attached.
Stefan, Paul, Kiwamu,
Tonight, we conitued working on the PRMI carrier lock. It is getting stable again.
(PR3 DC-coupled oplev servo)
Locking the PRMI, we immediately noticed PR3 drifting, which resulted in lock loss in a few minutes after lock is acquired. This is something we already knew (see for example alog 13837). First, we decreased the PSL power to 5 W in order to reduce whatever the thermal effect on PR3. Then we worked on the oplev servo on PR3 to pin it down on a certain angle. Since the PR3 opelv loop had been modified to be AC-coupled (alog 14719 from this past October), we put it back to DC-coupled again. This was done by adding some zero-pole pairs in the existing M2 stage damping loop. The DC couepling filter now resides in FM9. See the attached for the new DC-coupled filter. The blue curve is the original AC-coupled open-loop TF and the red is the new DC-coupled one. Note that the overall gain in the plot is not adjusted. The DC-coupled PR3 oplev gave enough stability that we can then work on some ASC loops.
(ASC loops)
We then closed two ASC loops in order to maintain the PRMI at high build up. Currently we engage the follwoing loops; AS_A_45Q -> MICH and REFL_B_9I -> PRM. Since we have already setup the control filters and suspensions, we simply changed the input matrix without chainging the servo gains. Here are the input matrix elements that we used:
This gave more stable lock which could last more than 30 minutes. Most of the lock loss was due to just us trying to make some changes in situ. Also, we needed to engage the BS top mass length feedback in order to keep it for many minutes because of high seismic.
(BS oplev glitching again)
Even with the ASC loops engaged, the ASDC fluctuated a lot. It could fulctuate from 4000 counts to 40000 counts at low frequencies below 1 Hz. Apparently the low frequency signal was associated with some kind of fast angular motion which was visible in the REFL, POP and AS cameras. We then found that the BS oplev was glitching and therefore giving fast transient into BS. It looked like it was happening mainly in yaw. This needs a close look tomorrow.
Evan, Alexa
Following the preparation described in alog 15524, we made a ringdown measurement of both the x- and y-arm. For each arm, we locked the IR beam and ran the wfs to ensure maximum build up. We then turned the wfs off, and switched the input polarity of the MC common mode board to unlock the MC quickly (based on LLO's alog 11727 the MC has about a 15usec ringdown time). We used the relfected signal at the AS port to capture the ringdown. We repeated this measurement 10 times to have ample data for our uncertainities. We also measured the "off-resonance" ringdown, by unlocking the arm and misaligning the respective ETM. All the data can be found in /ligo/home/alexan.staley/Public/Ringdown/EX(Y)data (these folders are then split into locked and unlocked times). From this data we calculated the total loss:
X arm: 14310(100) ppm
Y arm: 15000(100) ppm
Based on the galaxy ITMY transmissivity (1.42%) this amounts to 800ppm of loss in the y-arm. Meanwhile, for the x-arm, the ITMX transmissivity is 1.39 % corresponding to a 410ppm loss in the arm. We are in the process of calculating the transmissivity of the ITMs based on our ringdown fit. Our code can be found in /ligo/home/alexan.staley/Public/Ringdown/proccess.py. The y-arm losses seems consitent with our scan measurements; however the x arm does not. These numbers are very sensitive to the transmissivity we use; so before we make an conclusion with this we should inprove our confidence in the transmissivity values.
I’ve attached the code, the data, and the plots in a zip file.
Also attached are a few representative plots with the arms locked and unlocked.
Also, Dave wants me to note that the inferred loss of 410 ppm in the X arm is probably wrong; we’ve just pulled the ITMX transmissivity from the galaxy website instead of extracting it from our data. This is in progress.
The time constant of the ringdown is half of the cavity storage time, and the cavity storage time is related to the arm reflectivities by an equation in Isogai (sec 4.3):
We've assumed that we know RE = 1 − 5×10−6.
Here are the values for the ITM transmissivities, as inferred from the ringdown data.
In summary, to within experimental error there is no anomalous loss in the X arm. In the Y arm, the anomalous loss is 1330(370) ppm.
An updated version of the code is attached, along with a document giving the expression for TITM in terms of the measured quantities.
Here I've assumed RETM = 1, as was done in the paper by Isogai et al.
[Edit: Alexa has pointed out that we need to use m1 = RITM(P0+P1), rather than the original Isogai formula m1 = P0+P1, since we are using a PD in reflection. I've updated the table and the attachments accordingly. The ITM transmissivities change slightly and the extra losses go up a bit, but the conclusions remain the same.]
| X arm | Y arm | |
|---|---|---|
| m1 | 201(5) mV | 153(5) mV |
| m2 | 70(13) mV | 467(30) mV |
| m3 | 203(16) mV | 114(12) mV |
| m4 | 1.863(13) ms | 1.778(12) ms |
| ITM transmission, TITM | 1.419(35) % | 1.366(36) % |
| Total loss, L | 14 310(100) ppm | 14 990(100) ppm |
| L − TITM | 120(360) ppm | 1330(370) ppm |
For posterity, the old, incorrect values for the ITM transmissions were 1.425(35) % for X and 1.37(4) % for Y. The incorrect values for the extra losses were 60(360) ppm for X and 1290(410) ppm for Y.
Check the assumption on ETM transmission? Our measurement is 3.6 ppm with a tolerance of 0.2 ppm for both LHO ETMs. https://dcc.ligo.org/LIGO-E1300313
Dave O, Elli, Kiwamu
We have improved the dynamic range of the scatter pictures we took last night. We did this by:
-Changng analog gain on the camera from 1023 to 100.
-Changing from 8 bit to 12 bit enconding
-Averaging over 100 images rather than just using one.
We now have a much clearer picture of scattering off of ETMy. We took an image of ETMy with IR locked and green misaligned. We then subtracted a background image with both green and IR misaligned. We plotted the images using log10 of the intensity. We have also included the same image plotted with linear intesnity, which can be compared directly to last night's image.
Daniel was seeing problems running excitations to the ISC EY integrators, but at the time was not seeing the same problems at EX. We restarted h1iscey to restart its awgtpman. Problems persist at EY and now EX is seeing intermittent excitations. We'll take a closer look tomorrow. This is not a filtermodule excitation channel, rather an excitation part in the model.
Evan and Alexa working on ringdown measurements Daniel and Dave changing h1iscex and h1iscey models Jim W. and Krishna working on seismic sensor correction 07:25 Jeff and Bubba moving 3IFO storage containers in the LVEA 07:32 Karen and Cris into the LVEA 08:57 Filiberto and Aaron cabling in the LVEA 09:16 Corey and Kiwamu to the squeezer bay 09:16 Filiberto to end Y to look at the illuminator and dust monitors 09:35 Jim W. and Krishna to the CER 09:46 Jim W. and Krishna back 09:56 Karen cleaning at mid Y 10:19 Dave to mid X to label racks 10:48 Karen leaving mid Y 10:54 Dave back 11:55 Bubba, Jeff and Andres done 3IFO work in the LVEA. LVEA is back to full laser hazard. 12:00 Filiberto and Aaron done 12:36 Kyle and Gerardo taking engine hoist from corner station to end Y 13:14 Cyrus to mid X, end X and end Y to work on surveillance cameras 14:20 Kyle and Gerardo done Cyrus done
J. Warner, K. Venkateswara
The LLO sensor correction was implemented at the rest of the test mass chambers, after installing it yesterday at ETMX. Plots are attached.
There is a significant difference in performance between chambers despite the CPS sensors showing about the same level of subtraction (~10). ETMY_Y shows only a factor of 2 improvement at 0.43 Hz, while ITMX shows the full factor of 10 improvement. We are not sure why this is the case yet, but we'll look linto the isolation loops tomorrow.
S. Dwyer, K. Venkateswara
Sheila helped me align ITMX. We then looked at the OPLEV to see if the sensor correction had improved the Pitch and Yaw of the optics. Once again, as we saw in 15498, the Pitch and Yaw remain unchanged, as they are dominated by Ry and Rz respectively as seen by the coherence. This will likely affect the cavity control as well, unless the WFS are on which we will try tomorrow.
Rz could be improved if we could reproduce Arnaud's results. Ry improvement will be harder.
All outdoor and indoor units are on site. Indoor units are all hung and refrigeration lines are being connected. Outdoor units will be set next week after the concrete pad is poured. Partition wall is up and sheet rock in place, taping and paint next week.
Evan and I found the ETMY and ETMX back to the distributed configuration and no longer in offloaded. Based on a dataviewer trend this got switched 12/09/2014 18:34 UTC. I have reverted them both back.
Kyle, Gerardo Moved engine hoist into VEA ~1340 - 1345 hrs. local -> Ran purge air compressors to confirm that 1 psi regulator was regulating at 1 psi
Bubba G. Andres R. & Jeff B. This morning, after placing a 4" wafer in the center of the container, we sealed the 3IFO Storage container #3 and moved it into its long term storage location. The C3 cover over the suspensions was arranged so as to allow free N2 circulation, (see photos below). Storage Container #2 was moved into the loading position and the cleanroom was moved back into place. The container is ready to accept the last group of suspension for storage. The six suspensions (the last of the SUS/TMS suspensions from the staging building) that were staged by the High-Bay door were also craned over the beam tube. These are the bulk of the suspension to be loaded into Storage Container #2.
Daniel, Patrick, Dave
we restarted h1iscex and h1iscey with Daniel's latest code. The DAQ was then restarted.
SheilaD, JimW, HugoP,
We updated the SEI Guardian on site. The update only impacts the BS chamber. It is a patch that allows switching the GS13s to low analog gain when in ST2 is DAMPED. The GS13 are switched back to high analog gain when ST2 is ROBUST_ISOLATED. This update was applied to prevent the ISI from tripping during 'kicks' of the BS, which are inherent to the commissioning tasks. Update details can be found in SEI aLog #662
JimW's WP can now be closed.
Hugo
I've made a simple change to the sus guardian. The impact will be that after the guardian changes the alignment of an optic, it sets the ramp time for the alignment slider back to a short time (2 seconds). This is a more convient ramp time when people are fine tuning alingments, this will just save us from always changing the ramp time by hand after we use the guardian.
The only changes to the code were to add one line ( line 301) at the end of the main of get_alinging_state
susobj.alignRampWrite(susconst.shortRampTime)
and to add a new parameter to susconst.py
shortRampTime = 2
Although this changes the ramp time setting before the first ramp has finished, the first ramp still finishes with the five second ramp time that was set when it started. If anyone wants to change the time for a particular optic that can be done in the same way that the ramp time for TMS was set to be 10 (look at the TMS guardian). I've committed the changes to SUS.py. which we are using an h1 version of, but not susconst since we are using a common file
K. Venkateswara
After the changes to the way BRS is used at ETMX, detailed in 15497, tilt-subtraction shows significant improvement. Attached files show ASD plots from 40k seconds of data from last night, when winds were barely a few mph at ETMX.
The first plot is in angle units. The blue line shows the ground seismometer output, the green shows the raw BRS output and the red curve shows the new tilt-subtracted super-sensor output. The roll-off at 5 mHz is due to the high-pass filter but most of the other difference is from the new tilt-subtraction. This is also clear in the coherence plot shown below - the coherence between the super-sensor and the T240 is less than the coherence between the T240 and BRS. The BRS ref is shown in cyan.
The tilt-subtracted super-sensor is tilt-free and reliable till ~30 mHz or so. Why is this important? For one thing, it can be used to do sensor-correction to Stage 1 of the BSC-ISI, while keeping tilt-reinjection at a minimum. This has the effect of reducing the microseism, which is a big problem at LLO and will be a problem here as well. This was shown recently in 15498.
Some data from last night when winds were at an incredible ~5 mph! :)
These instruments have just been sitting on thefloor with no insulation so Krishna Jim and I got them under Trillium igloos. We had trouble with the internal Cable routine and may revisit to improve that.
The seismometers may be a little better - I've attached a pdf showing the X, Y, Z channels on the HAM2, HAM5 and ITMY seismometers and the coherence between them.
ITMY in particular looks significantly different and shows much less coherence than it probably should. It also refuses to zero out very well when the 'zero' button is hit on the control unit for the seismometer.
An overnight measurement may be a bit more illuminating.
J. Warner, H. Radkins, K. Venkateswara
The data from last night looks about the same. Plots are attached. The ITMY_Z and HAM2_Y channels look odd at low frequencies. The rest look reasonable.
Jim, Hugh and I checked the U,V,W outputs from the seismometers and confirmed that they were within the +/- 2 V spec described in the STS-2 manual.
SudarshanK, TravisS, EvanH, AlexaS, RickS Using the Pcal beam localization cameras at both end stations, we took images of the ETM surfaces under three conditions: IR and Green resonating; IR only resonating, and Green only resonating. Attached below are two composite images composed of four separate images taken with the same camera settings: Upper Left: Xarm Green Lower Left: Xarm IR Upper Right: Yarm Green Lower Right: Yarm IR The images in the first composite were taken with the following camera settings: F8, ISO 200, 30 second exposure, WB-cloudy. For the second composite image the aperture was F29 (~13 times less light) The Yend camera was re-focused for the IR-only images, but the Xend camera was not re-focused.
Thomas Abbott at LLO applied the Pcal beam localization analysis the the LHO ETMY image to calculate the position of the center of the optic in the image from last Friday. The image below contains lines that indicate the center of the optic using the Pcal image analysis.
Attached is a picture of the original FirstContact (FC) sheet, circa ~Jan 2014, showing the "IAS window" which is a thinner film of FC in the central 3" of the larger sheet. To me, the shape of the FC window looks similar to the 3" ring showing up in green on the recent optic photo above. SYS is working with us to get our cleaning game plan together in order to remove the ring. As well, they are investigating other possible scenarios of where the ring came from if not the window. Note, there was a full FC sheet re-cleaning in March that apparently did not remove all of the ring that was left behind apon the removal of the first sheet. To be continued...
I've attached an overlay of (a) the SolidWorks CAD view of ETMy along the PCal camera path and (b) the PCal camera image of H1 ETMy (scaled and rotated). Since SolidWorks does not diffract the image viewed through the ETM optic, I indicate the shift in the ETM Telescope Baffle aperture as well. Three of the 4 bright areas are along the ETM Telescope Input aperture/baffle edge (a coincidence?). (The upper one is red.) One of the 4 bright spots does not correspond to any feature in the CAD image and is likely a spot of residual First Contact. As subsequently shown by the zoomed in PCal image using the Green Lantern flashlight (green LED) after venting (see entry #15635), it is simply a coincidence that the two prominent bright areas appeared to be along the ETM Telescope baffle aperture edge.
Travis/Betsy
This morning, we staged to put the ETMy QUAD monolithic structure back together. We vacuumed as much of the structures as we could. I re-first-contact-cleaned the ERM-front surface since it had been exposed to the elements since the last vent and showed much particulate dispite blowing it with N2. The FC cleaning worked and the surface looked improved. We then removed the ETMy test mass HR First contact (which has been on since it left CIT) and attached the 2 lower structures. Using the Genie, w transfered the completed lower structure to the silver pallet jack + 5-axis lift table. We then maneuvered the LS into place and attached it to the upper structure already on the ISI table. We removed all of the lifting EQ from the QUAD and stowed everything in the unused welding cleanroom. All went well. We did not suspend the QUAD - we'll start that on Monday.
In the above alog I state that we removed the ETMy-HR First Contact sheet in order to mate the chains togther. This MUST be a typo as we always remove the TM-AR FirstContact (not the HR) when we mate the chains together.
