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ID Date Author Typeup Category Subject Text Attachments
  2514   Fri Nov 6 12:45:21 2020 AidanUpdate2um PhotodiodesPhotodiode testing recovery statusEmbellished Chris's PD MEDM screen
a bit to illustrate controls in a diagram.
The representation of the RELAY SWITCH between
 MEDM.pngPD_sweep.png 
  2516   Mon Nov 9 15:49:58 2020 AidanUpdate2um PhotodiodesJPL PD resurrection (cont.)Okay - all the steps in the procedure of eLOG
2476 have been verified as working
  
  2517   Tue Nov 10 12:46:34 2020 AidanUpdate2um PhotodiodesJPL PD resurrection (cont.)Looks like the temperature difference between
the PD and the shield is relatively small.
Even the transients when the heater is applied
 temperature_diff_shield_v_PD.png 
  2519   Tue Nov 17 17:51:44 2020 AidanUpdate2um PhotodiodesAgilis piezo mirror installed in JPL PD testing apparatus I installed the Agilis mirror before the
lens and cryo-chamber. Used the USB interface
to align the beam onto the PD. So we can
 IMG_9401.jpgIMG_9400.jpg 
  2520   Thu Nov 19 16:25:30 2020 AidanUpdate2um PhotodiodesAgilis piezo mirror installed in JPL PD testing apparatus Here's the python code I used to control
this. 

I incorrectly used the Move to
 Screen_Shot_2020-11-19_at_4.27.17_PM.png 
  2524   Wed Dec 16 22:08:36 2020 anchalUpdateEquipment transferTook delay line box, compressed nitrogen cylinder and lens to 2um (Crackle) lab
Took a delay line box DB64 from
QIL from the WOPO table to the 2um (formerly
known as Crackle) lab. The box was marked
  
  2533   Wed Mar 3 16:14:18 2021 AidanUpdate2um PhotodiodesBringing 2um PD testing back onlineI ran the bright PD test on the photodiode
currenlty in the vacuum chamber. The test
was run at air and room temperature. I aligned
 Screen_Shot_2021-03-03_at_4.11.47_PM.png 
  2534   Thu Mar 4 13:37:51 2021 AidanUpdate2um PhotodiodesReference PD reading vs Power incident on viewportI measured the power incident on the cryo
chamber viewport and the reference PD reading
to calibrate the incident power. Data is
 POW_IN_vs_REF_PD.csvIMG_1107.jpg 
  2536   Wed Mar 10 17:20:26 2021 AidanUpdate2um PhotodiodesPumped chamber down briefly - connected vacuum gauge to the computer
I updated the SR560 settings for
the AC Photodiode readout going into the
ADC. They're now: AC coupled input, 2000x
 IMG_1204.jpgIMG_1200.jpgIMG_1191.jpgIMG_1190.jpgIMG_1199.jpg 
  2538   Fri Mar 12 16:29:36 2021 AidanUpdate2um PhotodiodesVacuum needs leak checkingI pumped the small vacuum volume down but
the pressure started rising as soon as I
turned off the vacuum pump. Closing the main
 Screen_Shot_2021-03-12_at_4.28.54_PM.png 
  2556   Fri Apr 16 11:27:01 2021 AidanUpdate2um Photodiodes2um DC photodiode voltage weird drift with no incident power[Aidan, Radhika, Nina]

We noticed that the DC channel
readout (FM30) of the JPL A1 photodiode is
 DC_2um_voltage_weirdness.png 
  2557   Fri Apr 16 13:05:05 2021 AidanUpdate2um Photodiodes2um DC photodiode voltage weird drift with no incident powerWe put the preamp output directly into
a multimeter and observed the same fluctuating
behavior as the DAC channel was changed.
 IMG_2132.jpgFM30_31_w_latter_filtered.pngIMG_2134.jpgbias_bypassed.png 
  2589   Wed Jun 16 17:17:12 2021 KojiUpdateGeneralI2 cellI was searching an I2 (Iodine) cells back
to the days of the laser gyro.

I found a likely box at a very
 P_20210616_170104.jpegP_20210616_170038.jpegP_20210616_170021.jpeg 
  2590   Fri Jun 18 10:15:14 2021 StephenUpdateCryo vacuum chamberTemperature sensor considerationsRTD thoughts - we have just been using
the sensors that were provided, without noticing
their constraints or deficiencies.
 RTD_Resistance_vs_Temperature_for_PPG102A6.png 
  2668   Wed Sep 15 08:33:39 2021 AidanUpdate2um PhotodiodesVideo review of 2um testing setup post A1 testinghttps://dcc.ligo.org/LIGO-G2102040

 
  
  2672   Tue Sep 28 08:23:11 2021 AidanUpdate2um PhotodiodesDistances between optics, collimating lens, focussing lens and photodiodePrecise distances required between:


fiber launcher and collimating
lens
focussing lens and beam waist 


accounting
 JPL_PD_collimating_lens_Optical_layout.pdfJPL_PD_optical_propagation_and_beam_size.pdf 
  2686   Mon Oct 25 16:10:51 2021 AidanUpdateCDSRestarted computers and front-end model following campus power outage Rebooted the workstations and FB4.

 Restarted the model on the
FB4:
  
  2687   Mon Oct 25 16:13:47 2021 AidanUpdateCryo vacuum chamberHeater left on - chamber got warmThe cryocooler was switched off last Thursday
to do testing on the JPL_PD. I turned the
heater back on during this testing and neglected
 Screenshot_from_2021-10-25_16-19-39.png 
  2689   Tue Oct 26 07:32:52 2021 AidanUpdateCryo vacuum chamberHeater left on - chamber got warmWe're at 300K as of 7AM this morning.




  
  2690   Tue Oct 26 08:43:38 2021 AidanUpdateCryo vacuum chamberCTC100 temperature alarm and heater shutoffInstructions on how to enable the alarm
and heater shut off for the CTC100.

Status: This reports
 Screenshot_from_2021-10-26_08-42-57.pngIMG_5371.jpgIMG_5396.jpgIMG_5401.jpg 
  2723   Tue Feb 22 07:53:06 2022 YehonathanUpdateWOPOWaking up WOPO{Shruti, Yehonathan}

On Friday, we came down to QIL
to poke around the WOPO setup. The first
  
  2725   Fri Feb 25 17:09:53 2022 shrutiUpdateWOPOWaking up WOPO - green beam[shruti, yehonathan]

SHG and 532 nm beam alignment

Yehonathan
brought over 532nm/1064nm laser goggles from
  
  2727   Wed Mar 2 14:38:55 2022 YehonathanUpdateWOPOWaking up WOPO - some more fiddling and a plan{Shruti, Yehonathan}

We made some a list of some random
questions and plans for the future. We then
  
  2728   Fri Mar 4 11:49:45 2022 shrutiUpdateWOPOWaking up WOPO - attempts at readout[Yehonathan, Shruti]

1. Doubling cavity and green beam

Since
we had left the lasers ON with the shutters
 LO_shot_noise.pdf 
  2731   Thu Mar 10 17:12:01 2022 awadeUpdateWOPOWaking up WOPO - attempts at readout[awade]

Good to see this experiment being
revived.
  
  2733   Wed Mar 16 12:22:44 2022 YehonathanUpdateWOPOWaking up WOPO - attempts at readout{Shruti, Yehonathan}

Yesterday, we measured a bunch
of noises.
 Moku_Noise.pdfPD_Connected_no_light.pdfDiff_Channel.pdf 
  2735   Tue Mar 22 09:19:38 2022 shrutiUpdateWOPOWaking up WOPO - back to green path[Yehonathan, Shruti]

Yesterday we went back to fiddling
with the green path. Soon after opening the
 before_opt.jpgaround_waveguide.png 
  2759   Wed Apr 20 00:12:12 2022 YehonathanUpdateWOPOStill figuring out the readout electronics and fixing of some stuff{Yehonathan, Shruti}

1. Grabbed 30Hz-3GHz HP spectrum
analyzer from the Cryolab. Installed it in
 20220419_153109.jpg20220419_164600.jpg20220419_184248.jpg20220419_184233.jpg 
  2760   Thu Apr 21 10:33:33 2022 shrutiUpdateWOPOStill figuring out the readout electronics and fixing of some stuff[Yehonathan, Shruti]

 

First we turned on the relevant
  
  2762   Mon Apr 25 11:08:35 2022 YehonathanUpdateWOPOStill figuring out the readout electronics and fixing of some stuff{Shruti, Yehonathan}

We realized that the PD amp circuit
only requires a 5V DC supply so we try that.
  
  2764   Thu Apr 28 14:12:20 2022 YehonathanUpdateWOPOStill figuring out the readout electronics and fixing of some stuff{Shruti, Yehonathan}

We went to the e-shop to investigate
the PD circuits. Completely confused about
 JustTIR.pdfTIR_WithCapacitors.pdfOnlyV_plus.pdf 
  2777   Thu Jun 2 10:28:26 2022 YehonathanUpdateWOPOInstalling 1811 PDs[Shruti, Yehonathan]

We took newport 1811
PDs, one from CTN lab (suspicious) and one
  
  2796   Wed Jul 20 15:55:41 2022 YehonathanUpdateWOPOInstalling 1811 PDs{Yehonathan, Paco}

We comfirmed that the DC ouput
of one of the 1811s is bad. We set out to
 Diabolo_Current_Power_at_PDs.png 
  2800   Tue Aug 23 22:23:06 2022 awadeUpdateWOPOInstalling 1811 PDsI recall at one point we had one of these
NF1811 with a broken power suply pin.  It
was from a limited production run with the
  
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