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ID Date Author Type Category Subject Text Attachments
  1247   Thu Apr 23 03:09:49 2015 ZachDailyProgressSiFiWindows installed, cryostat top with cavities placed in body, cavities realigned, lockedThese things happened over the
last few days but haven't been elogged.

  1246   Tue Apr 21 21:30:50 2015 ranaLab InfrastructureDrawingsLab Layout circa Feb. 2015 (according to Nic)Heavy Duty (14 gauge steel) cabinet w/o
glass doors, but with door storage ordered.

  1245   Tue Apr 21 14:19:16 2015 ZachLaserPurchasesFiber isolators arrivedWe bought some IO-H-1550APC
fiber isolators from ThorLabs last week.
They arrived today:
  1244   Fri Apr 17 05:15:26 2015 ZachLaserSiFiTest cavities rebuilt on cold plate, aligned, locked (separately)Given the level of noise I saw
in air with the table-mounted test cavity
yesterday (CRYO:1242),
  1243   Fri Apr 17 04:39:25 2015 ZachUpdateSiFiTwo 150mm wafers sent for dicingI sent two of our 150mm (~6")
wafers to be diced by American
Precision Dicing (Justin's recommendation).
  1242   Thu Apr 16 15:58:02 2015 ZachLaserSiFiGyro RFPDs installed, tuned, E cavity PDH tuned and cavity lockedWell, I got partway through
the plan for the day, anyway.

Rather than align the W
  1241   Wed Apr 15 01:19:14 2015 ZachLaserSiFiInput paths, frontal beat, test cavities set up and aligned, ready to lockI bought and received the last
optics I was missing (90R/10T BSs) last week,
so I began building the real experiment today.
  1240   Tue Apr 14 22:27:18 2015 ranaLab InfrastructureDrawingsLab Layout circa Feb. 2015 (according to Nic)Some
cabinet options (for storage of heav-ish
  1239   Mon Apr 13 11:24:32 2015 ranaNoise HuntingMechanicsPost and base vs. pedestal and forkIts a nice result. As you say, we are lacking
in good writeups about this topic. Mostly
they're plots in the iLIGO elogs
  1238   Sat Apr 11 23:42:03 2015 ZachNotesMechanicsPost and base vs. pedestal and forkTonight, I got to do an experiment
that I've wanted to do for some time
  1237   Sat Apr 11 19:03:58 2015 ZachElectronicsSensorsRL readout PDSeeing Hartmut's talk at the
last LVC meeting about innovative DC photodetector
designs (something necessary for future squeezed
  1236   Wed Apr 8 21:12:19 2015 DmassCryostatSiFiRe-evacuated large cryostatYou can make them yourselves if you want
with activated charcoal and stycast - you
just need to bake and pump to clean it. I
  1235   Tue Apr 7 16:24:18 2015 ZachCryostatSiFiGetter quoteApparently, the getter is made
by IRLabs themselves. They've quoted
me $690 for a replacement (see
  1234   Sat Apr 4 18:08:18 2015 ranaCryostatSiFiRe-evacuated large cryostatGood point. If you or Nic can find it,
please post some getter info and we can get
a spare just in case this one is already
  1233   Thu Apr 2 20:21:18 2015 ZachCryostatSiFiRe-evacuated large cryostatI roughed our cryostat back
down tonight. Remember, this model has
a getter that degrades over time when exposed
  1232   Thu Apr 2 01:03:33 2015 ZachLab InfrastructureSiFiRack set up, table cleared and real layout startedToday, I installed the shelves
into our rack and moved the electronics that
were on the table into it. I then cleared
  1231   Mon Mar 30 17:56:13 2015 DmassNoise HuntingNoise BudgetWest Photothermal Transfer Function Actually Measured

Loss vs T. Confused on error bars
  1230   Fri Mar 27 00:26:02 2015 ZachSummarySiFi - ringdownTaiwan cantilever phi vs. T (old but unreported)Before the LVC meeting, I had just
done a long steady-state Q measurement on
the Taiwan cantilever. I got too distracted
  1229   Thu Mar 26 20:06:02 2015 ZachCryostatSiFi - ringdownSmall cryostat reassembled, Taiwan cantilever in clamp, pumping down[Den, Chris, Nic, Zach]

Since my snafu before the
LVC meeting (CRYO:1225),
  1228   Tue Mar 24 14:34:26 2015 ranaThings to BuyVacuumCryostat unpacked (x-post from SUS elog)I opened one of the viewports today to
inspect it for window size. It does indeed
look like the AccuGlass 2.75 CF (there are
  1227   Mon Mar 23 14:23:09 2015 DmassNoise HuntingNoise BudgetWest Photothermal Transfer Function Actually MeasuredRan the modified Farsi code with temperature
dependance added in for:

Silicon Thermal Conductivity
  1226   Thu Mar 19 14:00:21 2015 DmassNoise HuntingNoise BudgetWest Photothermal Transfer Function Actually MeasuredRaw Data from photothermal TFs:

  1225   Thu Mar 12 18:45:50 2015 ZachCryostatstuff happensEpoxy messI
brought the cyrostat up to room temperature
today to do some work inside, and there appears
  1224   Tue Mar 10 03:51:42 2015 ZachDailyProgressSiFi - ringdownTaiwan cantilever long-term low-temperature phiI reported in the replied-to entry
that the Q of the Taiwanese cantilever at
low temperatures actually appeared to
  1223   Tue Mar 10 03:19:49 2015 ZachComputingSiFi - ringdownTemperature calibration and control changesIt was a little unclear to me how
the digital temperature control was supposed
to work as it was built, so I made some modifications
  1222   Sun Mar 8 18:14:39 2015 DmassNotesCavitySubtractionThe main thing I wanted to do with the
coherence+ beat @ 300K beat data is subtraction.

Equation 7.33 of Bendat
  1221   Sun Mar 8 17:18:52 2015 DmassNotesCavityCoherencesCoherence measurements:

  1220   Sun Mar 8 16:04:23 2015 DmassNotesCavity300K Transmitted Spectra from Dec 2014 runTransmissed RIN spectra

  1219   Sun Mar 8 15:20:10 2015 DmassNotesCavity300K PDH data from Dec runPDH error signal measurement:

  1218   Sun Mar 8 14:37:18 2015 DmassNotesCavity300K beat data from Dec runBeat raw ASD from 300K Dec measurement

  1217   Fri Mar 6 19:02:28 2015 ZachDailyProgressSiFi - ringdownQ at low temperature after reclamp… worse?The cantilever had cooled to around
100 K by this morning, so I set up the mode
ringer and began an active measurement on
  1216   Thu Mar 5 22:35:43 2015 ZachDailyProgressSiFi - ringdownTaiwan room-temp Q > 10^5, cooling nowOn Tuesday night, when I added
the Si spacer to the clamp, I measured a
Q of ~46000, but I noted that it had been
  1215   Thu Mar 5 22:20:06 2015 ZachLab InfrastructureCryoLN2 refilled, new dewar #102I called the campus service yesterday
morning to have the LN2 dewar refilled. They
got around to it today. New dewar number
  1214   Wed Mar 4 02:32:45 2015 ZachDailyProgressSiFi - ringdownSi spacer added to clamp holding Taiwan cantileverThe most recent measurements on
the Taiwan-sourced Glasgow-style cantilver
(see CRYO:1213)
  1213   Fri Feb 27 05:47:27 2015 ZachDailyProgressSiFi - ringdownTaiwan cantilever fundamental mode Q[Nic, Zach]

We measured the Q of the
fundamental (~106 Hz) mode of the Taiwan
  1212   Thu Feb 26 18:47:59 2015 ZachLaserM2 ISS3-mm diode dark current and noiseGiven that we see some excess noise
in our 3-mm Laser Components diodes (IG17X3000G1i),
especially with one of them, I went ahead
  1211   Wed Feb 25 04:29:49 2015 ZachDailyProgressSiFi - ringdownTaiwan cantilever has higher Q, going for cryo cycle now[Nic, Zach]

Nic got a Glasgow-style
cantilever from a group in Taiwan, and a
  1210   Tue Feb 24 05:17:04 2015 ZachDailyProgressM2 ISSFirst real M2 testTonight
I succeeded in using the M2 ISS readout board
and the 3-mm diodes to do some real intensity
  1209   Mon Feb 23 19:55:08 2015 KojiLaserM2 ISS3-mm diode initial noise measurementFrank had = PeterK had = It went to LHO

I wonder if it helps to use FEMTO's
DLPCA-200 that I have somewhere in my lab.
  1208   Mon Feb 23 17:57:49 2015 ranaLaserM2 ISS3-mm diode initial noise measurementIF the DC dark current is out of spec,
we might be able to get a replacement.
Might be specs on the website. I think Frank
  1207   Mon Feb 23 14:57:23 2015 ZachLaserM2 ISS3-mm diode initial noise measurementI was preparing to do an initial
test of the M2 ISS readout board with the
3-mm diodes on the SiFi test setup 
  1206   Fri Feb 20 05:41:04 2015 ZachDailyProgressLaserSimple ISS testI wanted to do some intensity feedback
testing, for two reasons:

Just to get used to using
  1205   Fri Feb 20 05:22:19 2015 ZachDailyProgressLaserError calibration -> actuation TFs and new laser frequency noise measurementUsing the REFL PDH setup I built
the other day (and that was detailed somewhat
by Nic and Chris W. in CRYO:1204),
  1204   Thu Feb 12 15:34:12 2015 Nic, ChrisLaserTransfer Functionshigher bandwidth frequency readoutIn order to better measure the effect of
this nonlinear current to frequency modulation,
we'll need to do Zach's measurement
  1203   Wed Feb 11 03:58:52 2015 ZachLaserTransfer FunctionsWipf nonlinear temperature actuation proof of principleNic elucidated to me today Chris
W.'s idea for getting truly wideband
(~500 MHz) actuation out of our diode
  1202   Wed Feb 11 03:15:02 2015 ZachDailyProgressSiFi - ringdownOnly some extra damping is from wiresFollowing my preliminary conclusion
from yesterday (CRYO:1201),
I set out to confirm or deny this seeming
  1201   Tue Feb 10 04:37:05 2015 ZachDailyProgressSiFi - ringdownQ consistently lower in cryostatA lot of things happened tonight
(mostly in the realm of setbacks followed
by recovering frome them), but
  1200   Mon Feb 9 18:49:55 2015 ZachDailyProgressSiFi - ringdownQ ~ 6800 at room temp with Si sandwichAs I planned yesterday (CRYO:1199),
I tried out a new clamp using spare pieces
of broken silicon instead of sapphire washers
  1199   Mon Feb 9 02:59:28 2015 ZachLab InfrastructureSiFi - ringdownNew vacuum chamber for rapid room-temperature iterationIt is a little tedious waiting for a full
cryo cycle to iterate on the clamp. Also,
in many cases we can learn a lot from just
  1198   Sun Feb 8 02:49:27 2015 ZachDailyProgressSiFi - ringdownQ still low after clamp adjustments, mode cross-coupling suspectedThe cantilever was fully cooled
by the time I got in this afternoon. I measured
some quick ringdowns by looking at the amplitude
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