| ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
|
2907
|
Thu May 19 10:32:35 2022 |
rana | DailyProgress | PSOMA | new PSOMA cavity configuration | |
|
|
Draft
|
Thu May 19 10:16:04 2022 |
aaron | DailyProgress | Noise Budget | | I locked the cavity and added a 90-10 BS
after the MC2 cantilever mirror to send transmission
to both a DC PD and camera (90% reflection |
|
|
2905
|
Wed May 18 19:32:57 2022 |
aaron | DailyProgress | PSOMA | new PSOMA cavity configuration | I used the LB servo's input offset
to null the current drive (with both inputs
disconnected). Also moved the PDH error signal |
|
|
2904
|
Wed May 18 13:39:00 2022 |
shruti | DailyProgress | PSOMA | new PSOMA cavity configuration | Here
are the calculations for the mode mismatch
between the horizontal (tangential) and vertical |
|
|
2903
|
Wed May 18 12:56:35 2022 |
aaron | DailyProgress | PSOMA | new PSOMA cavity configuration | I added the South EOM into the fiber path
for the Teraxion laser. With the modulation
on, I now see the PDH error signal while |
|
|
2902
|
Wed May 18 11:19:34 2022 |
shruti | DailyProgress | PSOMA | new PSOMA cavity configuration | With the current high power level (~40
mW) entering the cavity, I was able to align
so that I could visibly observe one round |
|
|
2901
|
Tue May 17 14:28:09 2022 |
aaron | DailyProgress | PSOMA | new PSOMA cavity configuration | Shruti tells us that our 1m curved mirror
operated at 45 degree incidence as MC1 will
introduce a 6-7% power mismatch due to astigmatism. |
|
|
2900
|
Fri May 13 15:02:29 2022 |
rana | DailyProgress | PSOMA | new PSOMA cavity configuration | An added comment to Aaron's entry below:
Let us use the naming convention
which is commonly used in LIGO: |
|
|
2899
|
Fri May 13 12:57:30 2022 |
aaron | Lab Infrastructure | Vacuum | leak checking cryo cantilevers vacuum | Jordan will soon bring over the leak checker
to debug our Statlin cryostat.
I powered up the vacuum gauge and |
|
|
2898
|
Thu May 12 11:22:44 2022 |
aaron | DailyProgress | PSOMA | aligning | [shruti, aaron]
We switched to the teraxion laser
today for a higher power to be able to align |
|
|
2897
|
Wed May 11 14:11:15 2022 |
aaron | DailyProgress | PSOMA | aligning | Thanks, that description was very helpful
for understanding the state of the cavity
as soon as I walked in. |
|
|
2896
|
Wed May 11 12:42:04 2022 |
shruti | DailyProgress | PSOMA | aligning | Initially I began with the procedure in
elog 2895, but realized that the height of
the beam was not parallel to the surface |
|
|
2895
|
Tue May 10 14:56:42 2022 |
aaron | DailyProgress | Optics | measured scatter for a while, but here's the cavity alignment procedure | Continuing with alignment.
There are several spurious oscillations
(10s of Hz, few kHz, few MHz) on the REFL |
|
|
2894
|
Tue May 10 14:05:56 2022 |
shruti | DailyProgress | Optics | Replaced the cavity input coupler with 99.994% R optic for higher finesse cavity | I switched the optic so the HR surface
is inside the cavity. Still working on the
alignment. |
|
|
2893
|
Thu May 5 17:09:06 2022 |
aaron | DailyProgress | PSOMA | loop TFs and noise spectra | [shruti, aaron]
For sanity purposes, we also plotted
the frequency noise spectrum as recorded |
|
|
2892
|
Thu May 5 17:01:40 2022 |
shruti | DailyProgress | Optics | Replaced the cavity input coupler with 99.994% R optic for higher finesse cavity | [shruti, aaron]
We replaced the 90-10 BS used as
the input coupler to the cavity with the |
|
|
2891
|
Thu May 5 14:09:42 2022 |
aaron | DailyProgress | PSOMA | loop TFs and noise spectra | I noticed that the oscilloscope was still
plugged in to a network switch, but the switch
itself was not plugged in to the router. |
|
|
2890
|
Wed May 4 15:52:56 2022 |
shruti | DailyProgress | PSOMA | loop TFs and noise spectra | After some troubleshooting I realized that
I was mistakenly measuring the PDH signal
coming from the not-in-use north laser PDH |
|
|
2889
|
Tue May 3 16:34:19 2022 |
Chris | DailyProgress | PSOMA | current driver connections and cantilever acoustic damping | I opened the LIGO current driver chassis
for the north laser, to check its PCB revision.
It is v5 and will need modifications similar |
6x |
|
2888
|
Tue May 3 15:34:15 2022 |
aaron | DailyProgress | PSOMA | loop TFs and noise spectra | I updated the calibrated noise budget based
on Shruti's data above.
Shruti: Attachment 2 is |
|
|
2887
|
Tue May 3 09:51:42 2022 |
shruti | DailyProgress | PSOMA | loop TFs and noise spectra | Loop
transfer functions
[Attachment
1] |
|
|
2886
|
Fri Apr 29 11:21:51 2022 |
shruti | Update | PSOMA | Switch current driver to custom low noise | Using the delay line setup with a digital
PID slow control on the Moku:Pro in multi-instrument
mode, I first calibrated the delay line by |
|
|
2885
|
Thu Apr 28 14:44:28 2022 |
aaron | Update | PSOMA | Switch current driver to custom low noise | [shruti, aaron]
PDH calibration
Later
in the afternoon, we again measured the PDH
error signal sweep driving with 2V from the |
|
|
2884
|
Thu Apr 28 11:19:24 2022 |
shruti | Update | PSOMA | Switch current driver to custom low noise | [chris, shruti, aaron]
We turned down the current
on the Thorlabs ITC502, rack mounted the |
|
|
2883
|
Thu Apr 28 06:12:14 2022 |
Chris | Electronics | PSOMA | Current driver repair/upgrade | One of the D1200719
current driver boards (S1500270)
was in the EE shop for repair after some |
|
|
2882
|
Tue Apr 26 16:18:11 2022 |
aaron | Noise Hunting | Noise Budget | calibrating PDH error signal | I'm grabbing the pdh error signal from
the oscilloscope over ethernet (labutils/tektronix/tek-grabber.py),
and will calibrate the PDH error signal. |
|
|
2879
|
Tue Apr 26 14:28:51 2022 |
aaron | Things to Buy | Optics | high reflectors in lab | We have been wondering about the availability
of high reflecting optics for the PSOMA cavity,
especially the input / output coupler at |
|
|
2878
|
Mon Apr 25 13:54:03 2022 |
shruti | Noise Hunting | Noise Budget | calibrating PDH error signal | After checking that the cavity locks, around
the same temperature and current set-point,
sweeping the current resulted in something |
|
|
2877
|
Thu Apr 21 18:13:36 2022 |
Ian MacMillan | Misc | Equipment Loan | Accelerometer/seismometer loan Wilcoxon 731A | Returned. See this
elog
|
|
|
2876
|
Wed Apr 20 15:48:07 2022 |
aaron | Noise Hunting | Noise Budget | calibrating PDH error signal | I'm calibrating PDH error signal first
to avoid recording data of 'dark noise'
with no PDH signal like yesterday |
|
|
2875
|
Wed Apr 20 14:27:41 2022 |
aaron | Lab Infrastructure | General | starting up after power outage | I'm turning on the lab electronics
after the planned outage this morning.
Turned on following electronics.
cymac1, |
|
|
2874
|
Tue Apr 19 14:50:00 2022 |
aaron | Noise Hunting | Noise Budget | photodiode dark noise measurement | Things still look pretty weird. Today I'll
measure the photodiode dark noise (the previous
curve was theoretical, based on the known |
|
|
2873
|
Tue Apr 19 12:07:46 2022 |
shruti | Lab Infrastructure | PSOMA | PSOMA table enclosure assembly | [Aaron, Shruti]
We managed to install one of the
HEPA filter units on our enclosure today, |
|
|
2872
|
Fri Apr 15 16:25:00 2022 |
rana | Noise Hunting | Noise Budget | laser frequency noise measurement | The ITC 502 has an analog input modulation
impedance of 10 kOhm, according to the manual.
How did you set up the 16 dB attenuation? |
|
|
2871
|
Thu Apr 14 13:45:08 2022 |
aaron | Noise Hunting | Noise Budget | laser frequency noise measurement | [shruti, aaron]
We are measuring the frequency
noise on the beat note between the north |
|
|
2870
|
Wed Apr 13 11:10:28 2022 |
aaron | Noise Hunting | Noise Budget | PSOMA noise budget | New measurements
Current noise
Measuring
current noise following the procedures in |
|
|
2869
|
Tue Apr 12 15:00:39 2022 |
Ian MacMillan | Misc | Equipment Loan | Accelerometer/seismometer loan Wilcoxon 731A | I borrowed a Wilcoxon
Seismometer Model number 731A from the
cryo lab. I am also going to borrow |
|
|
2868
|
Tue Apr 12 12:16:58 2022 |
Aaron | DailyProgress | Si fab | Basic cantilever scribe and break | This morning, I used the Dynatex scriber-breaker
at the KNI to make three silicon cantilevers
7cm x 1cm x 300um. These are similar dimensions |
|
|
2867
|
Mon Apr 11 16:30:12 2022 |
aaron | Noise Hunting | Noise Budget | PSOMA noise budget | We'd like to progressively improve
the noise performance of the PSOMA cavity
by updating a noise budget when we make changes. |
|
|
2866
|
Wed Mar 30 16:18:58 2022 |
shruti | DailyProgress | PSOMA | Mixing signal and pump (north and south) | I fixed the fiber connections, re-organized
the fibers a little, and finally was able
to see a little less than 1.5 mW of power |
|
|
2865
|
Tue Mar 29 16:03:40 2022 |
shruti | DailyProgress | PSOMA | Mixing signal and pump (north and south) | [shruti, aaron]
Summary
Our next step
is to try and lock both lasers to the PSOMA |
|
|
2864
|
Thu Mar 10 13:43:20 2022 |
aaron | Misc | Laser | mode matching and slow servo, three corner hat revisited | I'd like to improve the mode matching.
Since it takes a while, I'll also set
up a slow servo on the TEC controller to |
|
|
2863
|
Wed Mar 9 14:20:26 2022 |
aaron | DailyProgress | Electronics | updates to fiber patch cables, realignment, N laser in path, relock |
Replaced the patch cable carrying
PSOMA South laser from the fiber box to the
table with 2x P3-1550PM-FC-10 cables (one |
|
|
2862
|
Tue Mar 8 13:45:20 2022 |
aaron | DailyProgress | Electronics | second PDH box and EOM | Entered the lab around 1:30pm to measure
the frequency noise of the PDH error signal
with the cavity locked. But I found some |
|
|
2861
|
Thu Mar 3 13:09:25 2022 |
aaron | Noise Hunting | Laser | some noise budgets maybe | I came to measure to measure the laser
frequency noise budget and see what I can
learn. |
|
|
2860
|
Tue Mar 1 17:08:47 2022 |
shruti | Lab Infrastructure | PSOMA | PSOMA table enclosure assembly | [Aaron, Shruti]
We installed all acrylic panels
on the enclosure today [Attachment 1]. Doing |
|
|
2859
|
Wed Feb 23 17:23:35 2022 |
Chris | Electronics | PSOMA | current driver status | The current driver now in the EE shop for
troubleshooting (chassis S1500267/PCB S1500270)
looks to be a D1200719-v3 |
|
|
2858
|
Tue Feb 22 11:51:55 2022 |
shruti | Noise Hunting | Laser | laser transfer function and frequency noise | In the loop
model I had posted earlier a part of
the discrepancy in the calibration of the |
|
|
2857
|
Fri Feb 18 10:43:18 2022 |
aaron | DailyProgress | PSOMA | enclosure rails, laser noise | [aaron, shruti]
Yesterday (Thursday Feb 17), I
installed the rails for the PSOMA enclosure's |
|
|
2856
|
Fri Feb 18 10:40:04 2022 |
aaron | HowTo | Electronics | how to Moku on wifi | Instructions from liquid instruments (via
Rana) on controlling Moku from the ipad while
it is connected to the internet for data |
|