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ID Date Author Type Category Subjectup Text Attachments
  369   Tue Jul 18 09:13:08 2017 GabrieleGeneralMeasurementsShear and bulk losses in tantalaS1600525 has been coated in Fort Collins
with 480nm of pure tantala. I used the emasured
loss angles (after deposition, before annealing)
  370   Wed Jul 19 21:19:14 2017 GabrieleGeneralMeasurementsShear and bulk losses in tantalaTo quantify which of the fit below is the
most significant, I did a Bayesian analysis
(thanks Rory for the help!).
  238   Fri Dec 9 13:13:32 2016 GabrieleGeneralMeasurementsSilicon sampleSilicon wafer from WRS materials, diameter
3", thickness 356-406 microns.


  154   Mon Oct 31 12:51:13 2016 GabrieleGeneralMeasurementsSimulation of dilution factor and measured loss anglesI made a COMSOL simulation of our wafer
(75 mm with flats, 1 mm thick) with a 1 micron
thick coating (Tantala), and computed the
  72   Tue Aug 2 15:58:12 2016 GabrieleElectronicsDaily ProgressSix QPD functional and testedI finished populating the new four QPD
boards, and fixed the first one I populated
weeks ago. I tested all five new boards:
  265   Thu Jan 19 12:49:17 2017 GabrieleFacilityVacuumSkyhook installedThe SkyHook has been put in place and bolted
down to the floor.

  314   Wed Feb 22 13:56:15 2017 GabrieleElectronicsConfigurationSoftware improvements
created a single interface to move
the picomotors in front of QPD1 ... QPD4

command qpdcenter
  277   Wed Jan 25 16:12:05 2017 GabrieleGeneralDaily ProgressSome assembly
assembled the four in-vacuum periscopes
(no mirrors yet)
soldered kapton
wires to the four ESD board; the vacuum side
  83   Sun Aug 14 11:40:29 2016 GabrieleElectronicsDaily ProgressSome python code Today I wrote some auxiliary functions
that will be useful for the measurement system:

noise.py: set of functions
  305   Tue Feb 14 10:55:13 2017 GabrieleGeneralDaily ProgressSomething fishy with bay 4 of the new setupI did two set of measurements with the
new coated samples from Montreal. I reshuffled
the position in the two measurements. In
  81   Sat Aug 13 11:17:17 2016 GabrieleFacilityDaily ProgressSpot the differences   2016-08-11_14.52.04.jpg2016-08-13_11.07.38.jpg 
  103   Tue Aug 23 09:21:25 2016 GabrieleGeneralGeneralStatus of Mark Optics disksWe initially received 20 disks (75 mm diameter,
1 mm thickness) from Mark Optics. Here's
their status as of today
  50   Mon Jul 18 17:48:58 2016 GabrieleElectronicsConfigurationStatus of real time system and workstation[EricQ, Gabriele]

The real time system seems to be
working properly, except for the excitations:
  48   Mon Jul 18 14:29:07 2016 GabrieleGeneralDaily ProgressStatus of the test setupI checked that the QPD electronics works
as expected, and that I can acquire the signals
using the ADCs. A new model (x3cr1) is up
  242   Tue Dec 13 11:42:52 2016 GabrieleGeneralGeneralSteve Penn's model of loss angleThe plot below shows the best loss angle
we expect foer our samples, based on Steve
Penn's model of surface and volume losses
  80   Fri Aug 12 10:33:14 2016 GabrieleElectronicsConfigurationStorage added to cymac3Installed two new 2TB disks into the cymac3.
Also, the main disk has a 1TB partition with
the operating system, so I created a new
  444   Wed Dec 6 07:53:47 2017 GabrieleGeneralMeasurementsSubstrates from University Wafers2017-12-06

Four fused silica
substrates from University Wafers, 76.2mm
diameter / 0.5 mm thickness installed in
  308   Thu Feb 16 09:47:29 2017 GabrieleGeneralMeasurementsSummary of coating runs carried out at Montreal

  216   Tue Nov 29 17:02:06 2016 GabrieleFacilityNoise huntingSuspending the roughing pumpI suspended the roughing pump with four
springs. The reduction of the 58 Hz peak
is similar to what I got when the pump was
  336   Thu Mar 30 15:23:44 2017 GabrieleOpticsGeneralSwapped HeNe laser in CR0The JDSU HeNe laser 1103P that I was using
is dead. I swapped it with a JDSU 1125P borrowed
from the 40m.
  311   Fri Feb 17 13:44:47 2017 GabrieleOpticsDaily ProgressSwapped picomotor and re-alignmentSince I had recurrent problems with the
picomotors used for QPD3, I swapped them
with another Newport motorized mirror that
  379   Wed Jul 26 09:27:40 2017 ZachElectronicsModelingSweeping the space between ESD and sample2017-07-26

I ran a
sweep of the gap between the ESD and the
sample, first from .5 mm to 1 mm. That sweep
  195   Thu Nov 17 12:06:39 2016 GabrieleGeneralVacuumSwitching on the IGM moves the diskHere's a trend of the QPD signals when
the IGM was turned on:

  9   Mon May 2 11:46:45 2016 GabrieleFacilityDaily ProgressTable and vacuum chambers in the labElogs for the new Coatin
  10   Tue May 3 11:57:47 2016 GabrieleFacilityDaily ProgressTable and vacuum chambers in the labWe discovered a couple of days ago that
the table was sitting on three legs only
and the fourth one was dangling. I managed
  456   Tue Jan 30 15:56:36 2018 Gabriele, CraigElectronicsConfigurationTemporary data acqusition for PSL lab beat note and accelerometersWe set up the model x3tst to acquire at
65kHz four signals coming from the PSL lab:

  176   Thu Nov 10 17:04:05 2016 GabrieleGeneralNoise huntingTemporary second QPDThis morning I installed temporarily a
second QPD to monitor the input beam. The
goal was to understand where the vibrations
  124   Fri Sep 23 08:11:48 2016 GabrieleMechanicsDaily ProgressTest of the disk retaining ring motionIn brief, it doesn't work. The magnets
and coils are strong enough to push up the
ring with a sample inside, but the friction
  100   Mon Aug 22 12:01:52 2016 GabrieleGeneralGeneralTests of the dayDisk excited at 12:01pm. Exited the room
at 12:03pm.

Opened the chamber at about 2:30pm,
  67   Thu Jul 28 13:58:48 2016 Alena, GabrieleCleanDaily ProgressThe old chamber is now being cleaned and bakedCleaned the chamber in the washing machine
at 40m and started 48 baking at 120 C
  76   Wed Aug 10 10:04:35 2016 GabrieleMechanicsDaily ProgressThe prototype of the disk retain system is hereYesterday we received the prototype of
the disk suspension and retain system. Everything
looks good. I checked that the disk fits
  239   Mon Dec 12 08:42:44 2016 GabrieleGeneralMeasurementsThermoelastic losses in Si sampleFollowing the model from R. Nawrodt et
al. Investigation of mechanical losses
of thin silicon flexures at low temperatures,
  237   Thu Dec 8 15:32:04 2016 GabrieleElectronicsConfigurationTiming issue: is it a DAC issue?My previous
test showed that the timing drift was
somehow related to the output of the signal
  240   Mon Dec 12 14:15:53 2016 GabrieleElectronicsConfigurationTiming issue: is it a DAC issue?I swapped the DAC with another one, but
I see the same behavior in the output signal.
Here's a spectrum of the DAC output,
  244   Sat Dec 17 06:29:15 2016 ranaElectronicsConfigurationTiming issue: is it a DAC issue?I find sometimes that the probe configuration
can give these distorted signals. For the
Tektronix probes, its best to use a 500 MHz
  303   Fri Feb 10 17:16:28 2017 GabrieleMechanicsDaily ProgressTranslation stage to move retaining ringsThis afternoon I installed the picomotor
and the translation stage that will be used
to move the retaining rings up and down.
  304   Sat Feb 11 16:22:26 2017 GabrieleMechanicsDaily ProgressTranslation stage to move retaining ringsThe ring motion up and down was not very
smooth, again due to friction on the centering
  400   Wed Aug 9 15:57:28 2017 ZachElectronicsModelingTriangular Geometry2017-08-09

I compared
the triangular geometry to the original geometry
and the excitation was only improved
  224   Mon Dec 5 10:39:16 2016 GabrieleElectronicsConfigurationTrying to debug GPS time issueFor a long time I had problems with the
GPS time in frames being different from the
real one.
  227   Tue Dec 6 09:02:17 2016 GabrieleElectronicsConfigurationTrying to debug GPS time issueThings seems to be worse now. This morning
I injected noise at GPS 1165078533 (real
time, as obtained from the python command
  228   Tue Dec 6 10:38:19 2016 GabrieleElectronicsConfigurationTrying to debug GPS time issueUPDATE:

Now the time difference is about
30 seconds. It seems that the real time model
  229   Tue Dec 6 11:22:58 2016 GabrieleElectronicsConfigurationTrying to debug GPS time issueI swapped the SR signal generator with
an Agilent 33210A. Shut down and restarted
the cymac3. Now the command line GPS and
  231   Tue Dec 6 16:55:51 2016 GabrieleElectronicsConfigurationTrying to debug GPS time issueUpdate at 5pm, GPS times are still in sync.

  232   Wed Dec 7 08:14:05 2016 GabrieleElectronicsConfigurationTrying to debug GPS time issueUnfortunately, this morning the model time
is again wrong...

  235   Wed Dec 7 16:27:11 2016 GabrieleElectronicsConfigurationTrying to debug GPS time issueI put back the Stanford Reserch signal
generator. On a scope, the timing signal
looks good. There is a small ripple and some
  236   Thu Dec 8 09:26:10 2016 GabrieleElectronicsConfigurationTrying to debug GPS time issueFor the last ~day the difference between
the frontend GPS time and the machine GPS
time remained constant between -1 and -2
  165   Mon Nov 7 11:27:16 2016 GabrieleGeneralVacuumTurbo pump excites some resonance at 58 HzI looked into a couple of turbo pump switch
on periods, and in both cases when the pump
speed hits 58 Hz, a resonance is excited.
  498   Tue Mar 27 16:37:22 2018 GabrieleGeneralVacuumTurbo pump for test chamber CR0 set pointI changed the set point of the test chamber
turbo pump to 666 Hz. This was done
by setting the "standby rotation speed"
  326   Thu Mar 2 11:27:47 2017 GabrieleGeneralNoise huntingTurbo pump of CR0 pollutes CR1The turbo pump of the CR0 chamber runs
at 833 Hz. It causes vibrations that pollute
the measurements in the CR1-4 chamber. In
  414   Wed Aug 16 16:05:09 2017 ZachElectronicsModelingTwo ESD First test2017-08-16

I created
a model with two ESD's, essentially a
combination of my previous two attempts with
ELOG V3.1.3-