| ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
|
361
|
Tue Sep 14 20:18:35 2010 |
tara | DailyProgress | Computers | pwr monitor for NPRO is added | C3:PSL-NPRO_PWRMON channel, and npro.db
file are added
for monitoring power output of the |
|
|
362
|
Wed Sep 15 22:43:41 2010 |
tara | DailyProgress | PMC | checking pmc servo | I checked PMC circuit to make sure that
the schematic matches the actual board.
This is important because we want |
|
|
367
|
Mon Sep 20 19:48:13 2010 |
tara | DailyProgress | PMC | PMC servo TF is fitted by LISO | I
fitted the TF of PMC servo card simulated
from LISO, and found poles at 2.01 Hz, 59.7 |
|
|
368
|
Mon Sep 20 20:57:40 2010 |
tara | DailyProgress | PMC | a part of PMC servo is verified |
I
measured PMC's TF between MIXER OUT and PCMON, |
|
|
369
|
Tue Sep 21 10:43:35 2010 |
Koji | DailyProgress | PMC | PMC servo TF is fitted by LISO | Hoo! So beautiful fit!
|
|
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371
|
Mon Oct 4 21:05:21 2010 |
tara | DailyProgress | PMC | PMC open loop TF | I checked the PSL setup today,
and the PMC gain setup has to be changed
from 30 dB (maximum on gain slider) to 22.5 |
|
|
391
|
Thu Nov 11 22:50:14 2010 |
tara | DailyProgress | BEAT | beat noise measurement | I
measured the beat note signal from two different
setup (f modulation) and plot the result |
|
|
392
|
Mon Nov 15 18:05:34 2010 |
tara | DailyProgress | BEAT | coherence <fbeat|RCAV>, <fbeat|ACAV> | I realigned the beam to PMC,
ACAV, RCAV, optimized gain, and find a significant
coherence between ACAV_RCTRASPD and RCAV_TRANSPD. |
|
|
393
|
Mon Nov 15 19:22:58 2010 |
rana | DailyProgress | NoiseBudget | Preparation to suppress intensity noise. | We need to see a plot of the coherence
between the PMC trans and Rcav trans and
the Acav trans. Also the RIN of all 3 plotted |
|
|
394
|
Tue Nov 16 03:36:55 2010 |
tara | DailyProgress | NoiseBudget | Preparation to suppress intensity noise. | I modulate the laser power @ 100Hz
and measure RIN from PMC,RCAV,ACAV trans
and beat note at 100 Hz, t |
|
|
396
|
Thu Nov 18 00:28:28 2010 |
koji, tara | DailyProgress | NoiseBudget | Noise from scattering light near the cavity's foam cap opening | Today we improved some frequency
noise by reducing the scattering light at
the ACAV's foam cap. |
|
|
397
|
Thu Nov 18 03:10:03 2010 |
Koji | DailyProgress | NoiseBudget | Noise from scattering light near the cavity's foam cap opening |
Even after the removal of the
Al tip,
the scattered light noise looks still exist.
|
|
|
398
|
Thu Nov 18 14:17:45 2010 |
tara | DailyProgress | NoiseBudget | Noise from scattering light near the cavity's foam cap opening | The Voltage vs Frequency conversion for
VCO is here.
It's not linear over the range. I |
|
|
399
|
Thu Nov 18 15:09:22 2010 |
Koji | DailyProgress | NoiseBudget | Noise from scattering light near the cavity's foam cap opening | What about the frequency response. Why
did we see the different shapes between the
spectra even with the coherence ~1. |
|
|
400
|
Thu Nov 18 21:42:33 2010 |
tara | DailyProgress | NoiseBudget | Noise from scattering light near the cavity's foam cap opening | I measured the calibration df/dV
for VCO to be ~48 kHz/V. Then I convert the
Vnoise fro VCO to frequency noise. |
|
|
401
|
Thu Nov 18 22:23:20 2010 |
Koji | DailyProgress | NoiseBudget | Noise from scattering light near the cavity's foam cap opening | TRANSFER FUNCTION!
|
|
|
402
|
Fri Nov 19 01:21:53 2010 |
tara | DailyProgress | NoiseBudget | Noise from scattering light near the cavity's foam cap opening | Here is the TF of LIGO's VCO. I measured
the TF at 3 different RF output voltage levels
(C3:PSL-FSS_VCOMODLEVEL) and plotted them |
|
|
403
|
Fri Nov 19 01:24:03 2010 |
tara | DailyProgress | optic | changing Faraday Isolator's mount/ TF from ACAV path | I switched the post to V-block for Faraday
Isolator mount, for better stability, and
adjusted the Faraday isolator to minimize |
|
|
404
|
Fri Nov 19 14:28:28 2010 |
tara | DailyProgress | BEAT | TF comparison between PLL feedback and VCO feedback | I measured the TF between VCO feedback
and PLL feedback. The result agrees with
the TF of the VCO. |
|
|
405
|
Fri Nov 19 14:36:19 2010 |
Koji | DailyProgress | BEAT | TF comparison between PLL feedback and VCO feedback |
|
|
|
406
|
Fri Nov 19 22:35:10 2010 |
tara | DailyProgress | NoiseBudget | Noise due to RIN | I measured the RIN of PMC/ACAV/RCAV
and noise in beat note when 250mV white noise
was injected in the laser current actuator. |
8x |
|
407
|
Sat Nov 20 13:30:30 2010 |
rana | DailyProgress | NoiseBudget | Noise due to RIN | You have to post here the TF between the
laser current actuator and the PMC trans
PD. Then, you should think about how to make |
|
|
408
|
Mon Nov 22 10:32:33 2010 |
tara | DailyProgress | NoiseBudget | Noise due to RIN | setting up the gain for intensity servo
1) TF of current actuator and PMC
trans PD: |
|
|
409
|
Wed Nov 24 01:53:10 2010 |
tara | DailyProgress | NoiseBudget | Intensity Servo | I
modified Dmass' intensity servo, but the
servo is not working yet. |
|
|
412
|
Tue Nov 30 21:48:13 2010 |
tara | DailyProgress | RefCav | Cavities egienmode | I measured the beat signal and VCO
feedback signal to see a peak from cavities'
mode of vibration, there are 4 peaks from |
|
|
413
|
Tue Nov 30 22:41:31 2010 |
rana | DailyProgress | RefCav | Cavities egienmode | The FEA
page indicates that the first longitudinal
mode is at 13.9 kHz. I suggest to zoom in |
|
|
414
|
Wed Dec 1 00:19:20 2010 |
tara | DailyProgress | Laser | TF between Laser Current Actuator and PZT on NPRO | I measured the TF between the current
actuator of the laser and PZT on NPRO to
see how much the current actuator changes |
|
|
415
|
Wed Dec 1 22:07:05 2010 |
tara | DailyProgress | BEAT | beat vs Power Input | I measured the beat signal from 3
different power input levels, the signal goes down |
|
|
416
|
Fri Dec 3 01:34:02 2010 |
tara | DailyProgress | BEAT | Faraday isolator added behind the PMC | I added a Faraday isolator after
PMC and 35.5 MHz broadband EOM, now the noise
becomes less susceptible to the |
|
|
418
|
Sat Dec 4 00:12:21 2010 |
frank, tara | DailyProgress | BEAT | PD for PLL | The current PD for the 160 MHz beat
signal is 120MHz. We use a 2 GHz PD to compare
the results between two PDS, |
|
|
419
|
Sun Dec 5 18:36:10 2010 |
Frank | DailyProgress | BEAT | PD for PLL: additional information | some additional information:
the beat noise was measured as the
feedback signal to the VCO of the PLL, so |
|
|
420
|
Mon Dec 6 22:09:59 2010 |
frank, tara | DailyProgress | BEAT | replacing PMC, adding EAOM | Today we 1)replaced out PMC with
DMASS' PMC and get better transmission efficiency,
2) added EAOM to modulate the laser intensity |
|
|
422
|
Wed Dec 8 00:15:42 2010 |
frank, tara | DailyProgress | BEAT | LO phase noise | Today we
1) checked if LO phase noise
dominates at high f. It turned out that it |
|
|
423
|
Thu Dec 9 00:20:33 2010 |
tara | DailyProgress | Electronics Equipment | switching ACAV/RCAV RFPDs | I switched the RFPD between
RCAV and ACAV, now the gain for FSS loop
is set to 26 dB, but the beat signal does |
|
|
426
|
Fri Dec 10 18:14:47 2010 |
tara | DailyProgress | Foam | widen in-out holes on the foam box | I widen the beam holes on the outer foam
box. Now all the holes are ~ 0.75"
in diameter. |
|
|
428
|
Mon Dec 13 18:50:02 2010 |
frank, tara | DailyProgress | Foam | increase inner insulation holes' size | Today we increased the size of the
beam path on inner insulations for ACAV and
RCAV, cleaned vacuum chambers' windows, and |
|
|
429
|
Tue Dec 14 22:00:01 2010 |
frank, tara | DailyProgress | Foam | increase inner insulation holes' size | After we fixed the insulation, the noise
spectrum at low frequency became better.
|
|
|
432
|
Thu Dec 16 12:38:57 2010 |
Frank, Jan | DailyProgress | Environment | seismometer installed on PSL table | Jan and I installed one of his seismometers
on the PSL table to get some seismic data
for the noise projection. |
|
|
437
|
Mon Dec 20 19:55:11 2010 |
tara | DailyProgress | optic | rearraging optics for beat measurement | I 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 |
tara | DailyProgress | optic | rearraging optics for beat measurement | Beat 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 |
tara | DailyProgress | optic | rearraging optics for beat measurement | Both 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 |
tara | DailyProgress | optic | rearraging optics for beat measurement | I measured the beat noise after I realigned
all optics behind the cavities. The power
has not been reduced to 1 mW yet. |
|
|
444
|
Mon Dec 27 23:11:32 2010 |
tara | DailyProgress | NoiseBudget | RIN coupling to frequency noise | I modulated laser power to see how
it causes frequency noise in the cavity,
no sign of RIN induced frequency noise has |
|
|
445
|
Tue Dec 28 05:24:16 2010 |
rana | DailyProgress | NoiseBudget | RIN coupling to frequency noise | To get a sensitive measurement, you should
measure a coherent transfer |
|
|
452
|
Mon Jan 24 21:02:15 2011 |
tara | DailyProgress | NoiseBudget | RIN coupling to frequency noise | I'm
measuring the TF between ACAV (ref) and
feedback to VCO (response). |
|
|
454
|
Tue Jan 25 16:30:16 2011 |
Tara, Frank | DailyProgress | Electronics Equipment | RCAV RFPD fixed | we replaced the photodiode in the RFPF
fro the reference cavity (RCAV). The old
one looked like shit. Below pictures of the |
|
|
456
|
Fri Jan 28 13:35:35 2011 |
Tara, Frank | DailyProgress | Electronics Equipment | RCAV RFPD fixed | The TF of 2 35.5MHz RFPD |
|
|
457
|
Sun Jan 30 22:58:35 2011 |
Tara | DailyProgress | Electronics Equipment | RCAV RFPD fixed | I adjusted
the temperature on ACAV and RCAV so that
both cavities can be locked simultaneously. |
|
|
465
|
Wed Feb 2 13:48:22 2011 |
tara | DailyProgress | BEAT | Comparison bewteen beat from PLL and FC | I used PLL feedback to measure beat noise
from dc to 3 Hz and dc to 1.5 Hz to compare
with the data taken yesterday by FC. |
|
|
470
|
Fri Feb 4 01:03:47 2011 |
Frank | DailyProgress | BEAT | cable delay setup | changed the frequency noise readout to
the cable-delay version to see how it works.
|
|