one of these signals does not look like the others: explanation?

We ought to put the camera software on the shared disk; I don't think there's any speed reasons that it needs to be local.

Its OK to use optimus as the camera server for testing at the moment, but once we have things running, we'll install a few more cameras. With ~4-5 GigE running, we may not want to share with optimus, since we're also using it for comsol and skymap calculations.

That's a new failure mode. Probably we can't trust the power to be safe anymore.

Need Steve to order a couple of surge suppressing power strips for the monitors. The computers are already on the UPS, so they don't need it.

I think the most important next two items to budget are the optical lever noise, and the coil driver noise. The coil driver noise is dominated at the moment by the DAC noise since we're operating with the dewhitening filters turned off.

I tried to get some minute trend data today, but was unable to get it from inside or outside the control room using our matlab or python tools.

It seems the NDS2 interface will not work anywhere since it needs our minute trends to be written as frames; in the last version that Jamie left us, our minute trend frame files are not being written since they lead to periodic daqd crashes.

From inside the control room, we can get the minute trend (only with DataViewer). I've attached 30 days of BS_X just to show its real.

We can get the numerical data from the Grace plot window using the menu option Data->Export->ASCII.

You must select all of the 'Write Sets' to get all of the traces in the plot window. The resulting ascii file is not in a great format, but its not terrible.

That's a good find.

1. The OL control signal can be gotten from the DQ error signal. You just need to multiply it by the digital filters and the gain. The state of the filters and the gain can be gotten using matlab tools like getFotonFilt.m. For python ChrisW wrote a tool called foton.py which is in the GDS SVN. You should ask him for it. It requires access to some ROOT libraries to run.
2. We should have sub budgets for everything like OL and thermal, etc. They should be automatically produced each time you run the main budget and should be separate pages in the same PDF file. Jamie / Chris may have something going along these lines so check to see if they are already on it.

I rebooted megatron around 12:20 today. It had dozens of stalled medm process (some of them there since February!). I couldn't kill them without them coming back like zombies, so I did sudo reboot.

I believe the ETMs and ITMs are different from the others.

I did an 'svn update' in userapps/cds/ which pulled in some changes from the sites as well as various CDS utilities in common/ and utilities/

This was to get Keith Thorne's get_data.m and get_data2.m scripts which I tested and they seem to be able to get data. No success with getting minute trend yet, but that may be a user error.

Update Monday 15-May: Our version of NDS client is 0.10 and we need to have 0.14 for this new method to work. Ubuntu12 lscsoft repo doesn't have newer nds client so we'll have to upgrade some OS.

this is not the right one; this Ethernet controlled strip we want in the racks for remote control.

Buy some of these for the MONITORS.

1. Include several sources of error. Micrometer error is one, but you should be able to think of at least 3 more.
2. There should be an error bar for the x and y axis.
3. Also, use pdftk to put the PDFs all into a single file. Remove so much whitespace.
4. Google 'beautiful plots python' and try to make your plots for the elog be more like publication quality for PRL or Nature.

Good installation. I think the images are still out of focus, so try to resolve into some small dots at the low exposure setting.

A few weeks ago we did some internet speed tests and found a dramatic difference between our general network and our internal Martian network in terms of access speed to the outside world.

As you can see, the speed from nodus is consistent with a Gigabit connection. But the speeds from any machine on the inside is ~100x slower. We need to take a look at our router / NAT setup to see if its an old hardware problem or just something in the software firewall. By comparison, my home internet download speed test is ~48 Mbit/s; ~6x faster than our CDS computers.

controls@megatron|~> speedtest
/usr/local/bin/speedtest:5: UserWarning: Module dap was already imported from None, but /usr/lib/python2.7/dist-packages is being added to sys.path
  from pkg_resources import load_entry_point
Retrieving speedtest.net configuration...
Testing from Caltech (131.215.115.189)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by Race Communications (Los Angeles, CA) [29.63 km]: 6.52 ms
Testing download speed................................................................................
Download: 6.35 Mbit/s
Testing upload speed................................................................................................
Upload: 5.10 Mbit/s
controls@megatron|~> exit
logout
Connection to megatron closed.
controls@nodus|~ > speedtest
Retrieving speedtest.net configuration...
Testing from Caltech (131.215.115.52)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by Phyber Communications (Los Angeles, CA) [29.63 km]: 2.196 ms
Testing download speed................................................................................
Download: 721.92 Mbit/s
Testing upload speed................................................................................................
Upload: 251.38 Mbit/s

Right - we want to be compatible with new version of the code, so instead of moving the files to where the code wants them you should make symlinks. The symlinkks go in the place that the code wants and points back to the place where we have the files now.

For the textoverlay, you can just comment it out for now. We can add it back in later once we decide on how to label the video.

With the network config, mounting, and symlinks setup, rossa is able to be used as a workstation for dataviewer and MEDM. For DTT, no luck since there is so far no lscsoft support past the Ubuntu14 stage.

wonder if its possible that the slow glitches in MC are just glitches in MC2 trans QPD? Steve sometimes dances on top of the MC2 chamber when he adjusts the MC2 camera.

I've re-enabled the WFS at 22:25 (I think Gautam had them off as part of the MC2 glitch investigation). WFS1 spot position seems way off in pitch & yaw.

From the turn on transient, it seems that the cross-coupled loops have a time constant of ~3 minutes for the MC2 spot, so maybe that's not consistent with the ~30 second long steps seen earlier.

i wonder how 'HDR' these images really are. is there a quantitative way to check that we are really getting more bits? also, how many bits does the PNG format allow for monochrome images? i worry that these elog images are already lossy.

Indeed, the whole point of the high/low gain setup is to never use the QPDs for the single arm work. Only use the high gain Thorlabs PD and then the switchover code uses the QPD once the arm powers are >5.

I don't know how the operation procedure went so higgledy piggledy.

Power meter only needed to measure power going into the paper not out. We use the BRDF of paper to estimate the power going out given the power going in.

The $1000 HeNe should not be used for illuminating fibers.

You should purchase these (total price per laser less than $6):

1. 10 red laser diodes for $2.39 total
2. 3-5 Vdc adapters

I have recommissioned the Zojirushi coffee pot lid. You may, once again, align the dots in order to make the carafe pourable.

Details:

The Zojirushi lid is a two part mechanism:

1. The top part of the lid must be removed for cleaning.
2. When replacing the lid the two components must be aligned to < 3 mrad precision so that the "teeth" are able to land in the groove.
3. There is a 4-fold degeneracy in this process. To break the degeneracy, align the dot on top with the spout gap (visible from the bottom view).
4. After proper alignment and mating, the two parts should snap together and the relative alignment wiggle available should be < 2 mrad.
5. After screwing the two-piece lid onto the carafe, ensure that the 2 dots are separated by < 170 deg in the closed position.

Hiro Yamamoto has updated SIS (Static Interferometer Simulation) to allow us to do the MCMC based inference of the 40m arm cavity mirror maps. 

The latest version is in git.ligo.org: IFOsim/SIS/

In the examples directory I have put 3 files:

1. mcmcCavityScans.m - runs many cavity scans using parfor and saves the data
2. plotCavityScans.m - loads the .mat file with the data and plots it
3. plotCavityScans.py - python file which also loads & plots, but nicer since python has a transparency option for the traces.

Attached is the plots and the data. The first attached plot is a low resolution one: 200 scans of 100 frequency points each. Second plot is 200 scans of 300 points each.

The run was done assuming perfect LIGO arm params with a random set of Zernike perturbations for each run. The amplitude of each Zernike was chosen from a Normal distribution with a standard deviation of 10 nm.

We need to come up with a better guess for the initial distribution from which to sample, and also to use the more smart sampling that one does using the MCMC Hammer.

Rana, Naomi

We dither locked the X arm and then aligned the green beam to it using the PZTs. Everything looks ready for us to do a mode scan tomorrow.

We got buildup for Red and Green, but saw no beat in the control room. Quick glance at the PSL seems OK, but needs more investigation. We did not try moving around the X-NPRO temperature.

Tomorrow: get the beat, scan the PhaseTracker, and get data using pyNDS.

same issue on NODUS; I edited the /etc/fstab and tried mount -a, but it gives this error:

controls@nodus|~ 1> sudo mount -a
mount.nfs: access denied by server while mounting fb1:/frames

needs more debugging - this is the machine that allows us to have backed up frames in LDAS. Permissions issues from fb1 ?

Tried getting trends with dataviewer just now since Jamie re-enabled the minute_raw frame writing yesterday. Unable to get trends still:

Connecting to NDS Server fb1 (TCP port 8088)
Connecting.... done
Server error 18: trend data is not available
datasrv: DataWriteTrend failed in daq_send().
unknown error returned from daq_send()T0=17-08-04-08-02-22; Length=28800 (s)
No data output.

These are not the angular test parameters that we're looking for:

 recall that what we want is the low frequency beam spot variations and the feedback to be limited to a small high frequency band.

e.g. only inject noise at 40-50 Hz, not loud enough to find at 2x the injected frequency.

It should NOT be the case that the high frequency injected noise be dominating the RMS.

The coupling should be ~1e-3; some combination of beam spot mis-centering and beam spot motion.

This kind of data fitting and analysis is really useful. We should figure out a way to archive it. Perhaps the data files and fitting stuff can be put into GIT in some smart way? The fit results can be added to the 40m MC electronics DCC tree. Then the links can be added to this elog.

Steve and I found the previous draft of the 40m Vacuum Document. Someone in 2015 had browsed into the Docs history and then saved the old 2013 version as the current one.

We restored the version from 2014 which has all of Steve's edits. I have put that version (which is now the working copy) into the DCC:  https://dcc.ligo.org/E1500239.

The latest version is in our Google Docs place as usual. Steve is going to have a draft ready for us to ready be Tuesday, so please take a look then and we can discuss what needs doing at next Wednesday's 40m meeting.

• Should we use the AD590 or the AD592? They're sort of the same, but have slightly different packages and specs.
• Given the sensitivity of the AD590 to power supply drift, I would recommend using a precision voltage reference like the AD581 or AD587. Take a look at the datasheets and order a few different varieties so we can see what works best for us. I believe that the voltage regulators have too much drift to use for precision temperature control.
• The AD590 datasheet has a few example circuits showing how we can subtract off the offset which comes the 1 uA/K coefficient of the AD590 (i.e. we would have 295 uA at room temperature, trying to stabilize to +/- 0.1 K)
• For the first prototypes its fine to use some solderable protoboard assembly, but we will eventually have to figure out how to package this thing and interface it with our Acromag slow controls system.

also, I've attached some temperature noise spectra from the LISA group at the AEI in Hannover. It will be interesting to see if we get the same results.

Might as well order several of a few different varieties today. Its good to have some extra in stock; we don't always want to have to wait days for parts to show up. If you give Steve a list of parts to buy he can order them today or Monday.

There should also be some precision 5V sources (e.g. AD586) that you can try.

To add to Gautam's entry: we swapped the cables at the coil driver side (these are the ones that go from coil driver to sat box). In this state, damping is not useable since the MC1 servos would drive MC3.

~70 counts in the sensor means ~70 microns of motion. Since the watchdogs are off and the coil drivers are swapped, this can't be laser beam getting in to the sensors.

WE have to consider that these are some real strain release type events happening in the suspension wire or wire standoff, so may require a vent to inspect and possible repair MC1.

Didn't someone look at what the OLG req. should be for these servos at some point? I wonder if we can make a parallel digital path that we switch on after green lock. Then we could make this a simple 1/f box and just add in the digital path (take analog control signal into ADC, filter, and then sum into the control point further down the path to the laser) for the low frequency boost.

Is it better to mount the box in the PSL under the existing shelf, or in a nearby PSL rack?

It seems like the main contribution to the RMS comes from the high frequency bump. When using the ALS loop to lock the arm to the beat, only the stuff below ~100 Hz will matter. Interesting to see what that noise budget will show. Perhaps the discrepancy between inloop and out of loop will go down.

I don't understand why the 1st order diffracted beam doesn't go to zero when you shut off the drive. My guess is that the standing acoustic wave in the AO crystal needs some time to decay: f = 40 MHz, tau = 1 usec... Q ~ 100. Perhaps, the crystal is damped by the PZT and ther output impedance of the mini-circuits switch is different from the AO driver.

In any case, if you need a faster shut off, or want something that more cleanly goes to zero, there is a large (~1 cm) aperture Pockels cell that Frank Siefert was using for making pulses to damage photo diodes. There is a DEI Pulser unit near the entrance to the QIL in Bridge which can drive it.

I have moved the USB flash drives from the electronics bench back into the middle drawer of the cabinet next to the AC which is west of the fridge. Drawer re-enlabeled.

I made a 'LiveCD' on a 16 GB USB stick using this command after the GUIs didn't work and looking at some blog posts:

sudo dd if=SL-7.3-x86_64-2017-01-20-LiveCD.iso of=/dev/sdf

K Thorne recommends that we use SL7.3 with the 'xfce' window manager instead of the Debian family of products, so we'll try it out on allegra and rossa to see how it works for us. Hopefully the LLO CDS team will be the tip of the spear on solving the usual software problems we have when we "~up" grade.

not immediately necessary, since you have already got it sort of working, but one of these days we should optimize this for real. In the past, we used to do this by putting a o'scope on the coil Vmon during the switching to catch the transient w/ triggering. We download the data/picture via ethernet. Run for loop on tolerance to see what's what.

The absence of evidence is not evidence of absence.

Larry Wallace hooked up a new switch (Brocade FWS 648G) today which is our 40m lab interface to the outside world internet. Its faster.

He then, just now, switched over the cables which were going to the old one into the new one, including NODUS and the NAT Router. CDS machines can still connect to the outside world.

In the next week or two, he'll install a new NAT for us so that we can have high speed comm from CDS to the world.

Image #1: No - we do not use magnetic mounts for beam dumps. Use a real clamp. It has to be rigid. "its not going anywhere" is a nonsense statement; this is about vibration amplitude of nanometers.

Image #2: No - we do not use sticky tape to put black glass beam dumps in place ever, anywhere. Rigid dumps only.

Image #3: Please do not ruin our nice black glass with double sticky tape. We want to keep the surfaces clean. This one and a few of the other Mickey Mouse black glass dumps on this table were dirty with fingerprints and so very useless.

Image #4: This one was worst of all: a piece of black glass was sticky taped to the wall. Shameful.

Please do not do any work on this table without elogging. Please never again do any of these type of beam dumping - they are all illegal. Better to not dump beams than to do this kind of thing.

All dumps have to be rigidly mounted. There is no finger contacting black glass or razor dumps - if you do, you might as well throw it in the garbage.

I have made several changes to Craig's script for better pythonism. Its more robust with different libraries and syntaxes and makes a tarball by default (w/o a command line flag). These kinds of general util scripts will be going into a general use folder in the git.ligo.org/40m/ team area so that it can be used throughout the LSC.

I don't think we need/want a coherence calculation, so I have not included it. Usually, we use coherence to estimate the uncertainty, and here we are just plotting it directly from the dist of the sweeps so coherence seems superfluous.

Steve, can you please connect this fan to the rack power and remove this extra power supply?

how about calibrate the DC channels so that you can just get the acutal power levels from the trend data?

these are not the SR785 settings that you're looking for

To get low noise measurements on the SR785, you have to have the input range set to -50 dB, not +20 dB. Its not within the powers of commercial electronics ADCs to give you a 10 nV noise floor with +10 V input signals. The SR560 has an input referred noise of 5 nV/rHz, so the output noise should be 5e-9 x 500 = 2.5 uV/rHz. Your picture shows it giving 1 uV RMS, so you also need to use the PSD units.

Backed up all the wikis. Theyr'e in wiki_backups/*.tar.xz (because xz -9e gives better compression than gzip or bzip2)

Moved old user directories in the /users/OLD/

why no oplev trace in the NB ?

also, this method would work better if we had a median averaging python PSD instead of mean averaging as in Welch's method.

I characterized the black Ithaca 1201 pre-amp that we had sitting in the racks. It works fine and the input referred noise is < 10 nV/rHz. I also checked that the filter selection switches on the front panel did what they claim and that the gain knob gives us the correct gain.

For comparison I have also included the G=100, 1000 input referred noise of one of the best SR560 that we have (s/n 02763) in the lab. Above a few Hz, the SR560 is better, but for low frequency measurements it seems that the 1201 is our friend.

As with the SR560, you don't actually get low noise performance for G < 100, due to some fixed output noise level.

Steve:  sn48332 of Ithaca 1201

I bet the calibration is out of date; probably we replaced the OL laser for the BS and didn't fix the cal numbers. You can use the fringe contrast of the simple Michelson to calibrate the OLs for the ITMs and BS.