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ID Date Author Type Categorydown Subject Text Attachments
  1994   Thu Nov 30 12:02:05 2017 awade, CraigDailyProgressscatterInitial buzz test and cleaning of periscope mirrors and final MM lens--- This is a backpost
from last week ---
  2022   Tue Dec 19 22:44:48 2017 awadeDailyProgressscatterBuzz test of beat boardI used the buzzer to help locate sources
of scatter in the transmission beat board. 

Here I used the SR785 in swept
  2023   Thu Dec 21 08:58:39 2017 CraigDailyProgressscatterScatter Shoulder FitI've been learning about scattering
from here
and here. 
  2026   Thu Dec 21 18:57:12 2017 awadeDailyProgressscatterSwitch out final MM lens in North pathAs pictured in PSL:1994,
there was a burn mark in the center of the
final lens before the north reference cavity. 
  2028   Fri Dec 22 14:38:24 2017 awadeDailyProgressscatterFixed bad PDH error signalIt turns out that the bad PDH signal
caused by monitor daughter board (D040424)
note being properly seated in its plug. 
  2033   Sun Jan 7 17:53:26 2018 Craig, awadeDailyProgressscatterScattering Sources Probably From Inside VaccanTL;DR We have (1)
poor alignment of light into the cavities
and (2) ghost
  2036   Mon Jan 8 14:46:09 2018 CraigDailyProgressscatterNorth Cavity Transmission BackreflectionYesterday I optimized the North cavity
visibility for a long time, and achieved
around 60% visibility, which is pretty good
  2064   Mon Jan 29 20:22:06 2018 CraigDailyProgressscatterPre-Vent Vaccan Tranmission Scattering DrawingI drew the basic scatterers I see when
viewing the inside of our vaccan from the
transmission port with the IR viewer. 
  2084   Fri Feb 9 18:36:40 2018 awade, CraigDailyProgressscatterScatter dumping around FSS reflection PDsI
reinstalled the green glass dump in the north
cavity FSS REFL PD prompt reflection path. 
  2093   Thu Feb 15 18:45:35 2018 CraigDailyProgressscatterNeed more Black Glass Hexagonal BasesMade nine black glass hex beam dumps today. 
Only stopped because we ran out of hex bases. 
Need to order more.
  2127   Fri Mar 9 16:10:41 2018 Craig, awadeDailyProgressscatter500 Hz resonant scatter hump in beatnote ASDIf you look at our
beatnote ASD you can see a broad dirty
hump at 500 Hz.
  2128   Sun Mar 11 16:50:59 2018 Craig, awadeDailyProgressscatter500 Hz resonant scatter hump in beatnote ASDAfter buzzing the table with a probe at
500 Hz, the source of the 500 Hz resonance
is the first steering mirror after the PMC. 
  2135   Thu Mar 15 10:29:04 2018 awadeDailyProgressscatterAddressing 500 Hz scatter pickupGoing back the original issue of scattering,
it appears that there is light being back
reflected from somewhere in the post PMC
  2149   Wed Mar 21 00:40:01 2018 CraigDailyProgressscatterThe Sentinels: Transmission Table Black Glass Beam DumpsScattering is a huge problem in our setup,
and we aren't sure where exactly the
offending scattering is coming from. 
  2150   Wed Mar 21 11:07:17 2018 awadeDailyProgressscatterThe Sentinels: Transmission Table Black (Green) Glass Beam DumpsWhich direction are you trying to dump?
Into or out-of the can?

The scatter going inward is being
  2152   Fri Mar 23 15:12:00 2018 CraigDailyProgressscatterPowerpoint Trans Table DiagramThis diagram will be for quickly keeping
track of scattering beams/scattering resonances
on the trans table.  Need to improve
  2155   Wed Mar 28 11:29:19 2018 awadeNotesscatterHigher quality vaccan windows: 40m stock of wedged windowsI just checked the 40m's stock of wedged,
AR coated, optics in the pull out draws. 
  2156   Wed Mar 28 15:29:42 2018 KojiNotesscatterHigher quality vaccan windows: 40m stock of wedged windowsThat was unfortunate. But why does BK7
uncompatible with the purpose? We need UV
fused silica only for the high power reason,
  2158   Thu Mar 29 11:14:52 2018 awadeNotesscatterHigher quality vaccan windows: 40m stock of wedged windowsI guess BK7 is fine, we're not going
to be putting high power in.  I just
though UV fused silica would be better practice
  2172   Mon Apr 16 16:23:09 2018 awadeDailyProgressscatterBeam size on trans BN detectorI thought I'd have a look at how big
the beam is on the current 1811 New Focus
detector. Over focusing here might be a source
  2174   Thu Apr 19 18:28:11 2018 ranaDailyProgressscatterBeam size on trans BN detector This beam is
WAY too big for the PD. If the beam radius
  2176   Sun Apr 22 22:00:15 2018 awadeDailyProgressscatterSwitching out NF1811 detector for KA25MHzRather than beating the NF1811 dead horse
any more I've switched it out for the
new KA 26 MHz detector.  
  2403   Wed Aug 28 09:49:44 2019 anchalSummaryscatterBeam Dump StatusWe need to switch out normal flat-faced
beam dumps with triangular cavity beam dumps
in all places where they are not present.
  2528   Mon Feb 10 17:41:25 2020 anchalDailyProgressscatterCleaned up table; Installed hex beam dumpsToday I cleaned up the table, removed Scott's
RFAM measurement setup and installed hex
beam dumps on the input rejection of faraday
  2533   Thu Feb 13 18:00:30 2020 anchalDailyProgressscatterblocked NF1811 with hex beam dumpI have blocked the unused output port of
the beam splitter before our beatnote detector
with a hex beam dump at (13,
  403   Fri Nov 19 01:24:03 2010 taraDailyProgressopticchanging Faraday Isolator's mount/ TF from ACAV pathI switched the post to V-block for Faraday
Isolator mount, for better stability, and
adjusted the Faraday isolator to minimize
  437   Mon Dec 20 19:55:11 2010 taraDailyProgressopticrearraging optics for beat measurementI designed the layout for optics behind
the cavities for beat measurement, and calculated
the mode matching for the beam.
  440   Thu Dec 23 22:41:28 2010 taraDailyProgressopticrearraging optics for beat measurementBeat measurement optics' height is changed
to 3". I cleaned all optics already,
but I couldn't really clean 1/2 and 1/4 wave
  441   Sun Dec 26 02:42:47 2010 taraDailyProgressopticrearraging optics for beat measurementBoth cavities are locked at the same time.
The temperature setting are, RCAV = 34.95,
ACAV = 37.2.
  442   Mon Dec 27 02:51:33 2010 taraDailyProgressopticrearraging optics for beat measurementI measured the beat noise after I realigned
all optics behind the cavities. The power
has not been reduced to 1 mW yet.
  599   Wed May 4 01:20:00 2011 taraDailyProgressopticminimizing RFAM/ aligning 35.5 MHz EOMI minimized
the RFAM by aligning the 35.5 MHz EOM and
  602   Wed May 18 20:51:35 2011 taraDailyProgressopticoptic layout for new fss setupI planned the layout for new fss setup.

The new setup has 1) both cavities
  603   Thu May 19 11:32:46 2011 taraDailyProgressopticoptic layout for new fss setupI added more details on the layout, and
necessary half wave plates in the beam path.
  605   Wed May 25 18:29:09 2011 taraNotesopticpurchasesI ordered a few opto mechanical components
to replace the current shaky periscopes.
The new  periscope is shown
  606   Mon May 30 15:23:53 2011 ranaNotesopticpurchasesThe periscopes for the refcav ought to
be made custom. None of the store bought
type are stiff enough. Koji has a design
  607   Tue May 31 11:31:18 2011 taraNotesopticpurchasesI looked up 40m elog and found Daisuke's
design for periscope. I'll make a sketch
FSS' periscopes.
  609   Wed Jun 1 01:50:35 2011 KojiNotesopticpurchasesThey are found in DCC. Some comments
- You can not steer the beam. The
beam should be steered before or after the
  610   Wed Jun 1 21:00:05 2011 FrankNotesopticpurchaseswe have to design our own. The 40m one
has 2" mirrors (too large, we don't
have the space), wrong height for incoming/outgoing
  614   Tue Jun 14 23:07:03 2011 taraDailyProgressopticoptic layout for new fss setupThe mode matching for new FSS is calculated.
The plan is shown below.
  628   Mon Jul 18 02:20:01 2011 taraDailyProgressopticoptic layout for new fss setup  The
new mode matching for optics in front of
the cavities is done.  The rest (for
  629   Mon Jul 18 11:41:22 2011 ranaDailyProgressopticoptic layout for new fss setupThere's no need to use such a large
spot size on either the AOM or the EOM. 
When using high power this could
  631   Wed Jul 20 15:54:21 2011 taraDailyProgressopticoptic layout for new fss setup  I edited the layout so that the
spots in both AOMs are 200 um. I'll list
what optics we might have to buy.
  632   Wed Jul 20 23:00:30 2011 FrankDailyProgressopticoptic layout for new fss setupthe lens and mirror are in the ATF, a second
VCO is in the left cabinet.
  636   Fri Jul 22 20:51:13 2011 frank, taraDailyProgressopticcleaning opto mechanical partsAs we removed some optics on the table,
we use pressurized air to blow away dust/dirt
on the mechanical parts (mount/ post/ lens
  640   Tue Jul 26 18:42:16 2011 raphael, taraDailyProgressopticcleaning opto mechanical partsToday we removed the optics behind the
PMC, ACAV, and cleaned the table.

      Optic mounts and
  644   Thu Jul 28 01:54:21 2011 frank, taraDailyProgressopticcleaning opto mechanical parts  Today we started working on the
layout. There is one mistake in the layout,
the mirror behind AOM for REFCAV is too close
  647   Fri Jul 29 00:42:19 2011 frank, taraDailyProgressopticcleaning opto mechanical parts We preparing optics for the new layout.
To reduce scattering noise, most of the Y1-1064
mirrors we have been using will be replaced
  648   Tue Aug 2 23:58:40 2011 taraDailyProgressopticNew RCAV setup is locked  RCAV is locked, I have not
optimized the mode matching yet, the coupling
efficiency is ~ 67%.
  653   Tue Aug 9 00:39:30 2011 taraDailyProgressopticRCAV modematching optimized I optimized mode matching for RCAV.
The coupling is ~75%.  I also minimized
RFAM from the 35.5MHz EOM.
  658   Mon Aug 15 23:13:53 2011 taraDailyProgressopticRCAV modematching optimized I recalculated the mode matching
so that the spot radius in AOMs is 100 um.
Now the visibility of RCAV is 90%.
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