ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
14486
|
Mon Mar 18 20:22:28 2019 |
gautam | Update | ALS | ALS stability test | I'm running a test to see how stable
the EX green lock is. For this purpose, I've
left the slow temperature tuning servo on |
|
10302
|
Thu Jul 31 01:08:54 2014 |
Koji | Update | LSC | ALS stability check | - ALS X/Y arm stability was checked by
IR locked arms.
- Basically the stability looks same |
|
13600
|
Fri Feb 2 13:16:55 2018 |
gautam | Update | ALS | ALS signals whitening switching | While setting up for this measurement,
I noticed something odd with the whitening
switching for the ALS channels. For the usual |
 |
13595
|
Wed Jan 31 22:32:11 2018 |
gautam | Update | ALS | ALS signal chain + power budget | Summary:
|
 |
13597
|
Thu Feb 1 15:31:12 2018 |
gautam | Update | ALS | ALS signal chain + power budget | Summary:
A |
|
13613
|
Wed Feb 7 10:16:26 2018 |
gautam | Update | ALS | ALS signal chain + power budget | After emailing the technical team at Menlo,
I have uploaded the more detailed information
they have given me on our wiki. |
|
9183
|
Tue Oct 1 17:14:53 2013 |
masayuki | Update | Green Locking | ALS servo filters modified |
[Manasa, Masayuki]
|
 |
8792
|
Wed Jul 3 01:49:46 2013 |
Annalisa | Update | Green Locking | ALS servo configuration | [Koji, Annalisa, Manasa]
Today we worked on the ALS servo
stabilization for the Y arm. |
 |
8793
|
Wed Jul 3 03:06:29 2013 |
Annalisa | Update | Green Locking | ALS servo configuration |
I realized that I cannot open the
attached plots. I'll fix them tomorrow. |
|
9861
|
Sun Apr 27 21:30:59 2014 |
Koji | Update | LSC | ALS servo characterization | The measured openloop TF of the ALS servo
for each was characterized by a ZPK model.
The openloop TF can be modeled by: |
 |
9171
|
Fri Sep 27 20:28:10 2013 |
manasa | Update | Green Locking | ALS servo | [Masayuki, Manasa]
I. ALS servo loops
After fixing things with the phase |
 |
8841
|
Fri Jul 12 23:13:32 2013 |
manasa | Update | Green Locking | ALS sensor noise | [Annalisa, Koji, Manasa]
In order to improve the ALS stability |
 |
14846
|
Thu Aug 15 18:54:54 2019 |
gautam | Update | ALS | ALS sensing noise due to IMC | Summary:
I came aross an interesting
suggestion by Yutaro that KAGRA's |
|
14847
|
Fri Aug 16 04:24:03 2019 |
rana | Update | ALS | ALS sensing noise due to IMC | What about just use high gain feedback
to MC2 below 20 Hz for the IMC lock? That
would reduce the excess if this theory is |
|
9122
|
Wed Sep 11 17:35:38 2013 |
Jenne | Update | LSC | ALS requirement | I have done a quickie look at Optickle
to see how the linewidth of an arm cavity
changes versus the configuration. |
 |
13180
|
Wed Aug 9 19:21:18 2017 |
gautam | Update | ALS | ALS recovery | Summary:
Between frequent MC1 excursions,
I worked on ALS recovery today. Attachment |
|
13519
|
Tue Jan 9 21:38:00 2018 |
gautam | Update | ALS | ALS recovery |
Aligned IFO to IR.
Ran
dither alignment to maximize arm transmission.
Centered
Oplev reflections onto their respective QPDs |
  |
12578
|
Mon Oct 24 11:39:13 2016 |
gautam | Update | General | ALS recovered | I worked on recovering ALS today. Alignments
had drifted sufficiently that I had to to
the alignment on the PSL table onto the green |
 |
11378
|
Thu Jun 25 18:20:15 2015 |
ericq | Update | LSC | ALS reconstruction in progress | I've been working on getting a working
ALS up and running. Things are in a bit of
a transient state right now; I'm off |
|
11379
|
Fri Jun 26 03:24:18 2015 |
ericq | Update | LSC | ALS reconstruction in progress | Too sleepy to make full ELOG. Stay tuned.
Two 25dB amplifiers (with fins!)
are living in the top shelf on the PSL table, |
|
11381
|
Mon Jun 29 12:28:45 2015 |
ericq | Update | LSC | ALS reconstruction in progress | Turns out the reason that the BEATY signal
wasn't working is that one of the two
RF amplifiers (both of which are model ZHL-32A), |
|
14995
|
Mon Oct 28 23:20:11 2019 |
gautam | Update | ALS | ALS power budget |
IR |
|
11679
|
Fri Oct 9 13:31:21 2015 |
ericq | Update | LSC | ALS plant shape | To get a better look at how to do fast
ALS, I took some "Plant TF"
measurements of the X arm. |
|
11680
|
Fri Oct 9 14:50:18 2015 |
Koji | Update | LSC | ALS plant shape | ALS is the comparison of the
PSL laser freq vs the
end laser freq that is locked to the arm |
|
11681
|
Fri Oct 9 16:23:25 2015 |
ericq | Update | LSC | ALS plant shape | Ah, I understand it now! Since the additive
offset path keeps the post-cavity frequency
TF flat, the pre-cavity frequency must grow |
|
13237
|
Mon Aug 21 23:38:55 2017 |
gautam | Update | ALS | ALS out-of-loop noise | I worked a little bit on the Y arm ALS
today.
Started by locking the |
|
9198
|
Thu Oct 3 13:54:25 2013 |
manasa | Update | Green Locking | ALS out-of loop noise | We found the PDH servo gain for Y arm green
was set at 2 (too low). The gain was set
to 8.6 (based on earlier OLTF measurement |
|
9906
|
Fri May 2 19:03:13 2014 |
Jenne | Update | LSC | ALS out of loop spectra | I have taken out of loop spectra for both
arms, by looking at POX/POY while the arms
were controlled with ALS. |
|
9015
|
Thu Aug 15 19:05:07 2013 |
manasa | Update | Green Locking | ALS out of loop noise | Beat notes were recovered for both the
arms.
I locked the arms to IR using PDH |
|
9694
|
Wed Mar 5 19:15:39 2014 |
Jenne | Summary | LSC | ALS offset moving script modified |
|
|
9646
|
Tue Feb 18 18:52:08 2014 |
Jenne | Update | LSC | ALS not locking with LSC | Koji mentioned to me (and elogged) that
he was unsuccessful locking the ALS using
the LSC servos. He suggested I look |
   |
9647
|
Tue Feb 18 20:31:29 2014 |
Koji | Update | LSC | ALS not locking with LSC | Hmm. Wierd. Can you look at the TFs between
ETMX-EXC and the error signals so that we
can identify which one has these structures. |
|
9648
|
Tue Feb 18 23:27:14 2014 |
Jenne | Update | LSC | ALS not locking with LSC | It looks like its somehow a discrepancy
between the TFs of each error signal, because
features are similar, and present, in both |
|
9832
|
Fri Apr 18 20:17:17 2014 |
Jenne | Update | LSC | ALS noisy | Last night, as well as tonight, the ALS
seems not quite as robust as it was earlier
in the week. |
 |
15046
|
Mon Nov 25 19:11:22 2019 |
gautam | Update | LSC | ALS noise re-look | I re-checked the ALS noise in the following
configurations:
PRM is misaligned.
Michelson |
|
15233
|
Thu Feb 27 22:45:40 2020 |
gautam | Update | ALS | ALS noise high | There was some UNELOGGED work at EX today.
The DFD outputs were also hijacked for loss
measurement. Unclear |
|
15617
|
Wed Oct 7 16:56:23 2020 |
anchal | Summary | ALS | ALS noise budget update - Updated AUX PDH Loop values | AUX PDH Loop update
I
used D1400293
to get the latest logged details about the |
 |
15619
|
Thu Oct 8 11:59:52 2020 |
rana | Summary | ALS | ALS noise budget update - Updated AUX PDH Loop values | For all the loops where we drive the NPRO
PZT, there is some notch/resonance feature
due to the PZT mechanical resonance. In the |
|
15622
|
Fri Oct 9 18:32:14 2020 |
anchal | Summary | ALS | ALS noise budget update - Updated AUX PDH Loop values | The only two PZT Phase modulation transfer
function measurements I could find are 40m/15206 |
|
15626
|
Wed Oct 14 17:03:55 2020 |
anchal | Summary | ALS | ALS noise budget update - Added whitening filter for ADC | Koji recommended that I can add whitening
filters to suppress ADC noise easily. I added
a filter before ADC in ALS loop with 4 zeros |
|
15587
|
Sat Sep 19 23:59:22 2020 |
anchal | Summary | ALS | ALS noise budget update | Setting the record straight
I
found out an error I did in copying some
control model values from Kiwamu's matlab |
    |
15589
|
Sun Sep 20 23:12:13 2020 |
rana | Summary | ALS | ALS noise budget update | I think the digital loop in the ALS budget
is too optimistic. You have to include all
the digital delays and anti-aliasing filters |
|
15593
|
Tue Sep 22 00:14:43 2020 |
anchal | Summary | ALS | ALS noise budget update | This is not a reply to comments
given to the last post; Still working on
incorporating those suggestions. |
 |
15594
|
Tue Sep 22 12:14:42 2020 |
rana | Summary | ALS | ALS noise budget update | This ALS loop is not stable. Its one of
those traps that comes from using only the
Bode plot to estimate the loop stability. |
|
15601
|
Wed Sep 23 11:13:49 2020 |
anchal | Summary | ALS | ALS noise budget update | Yes, that loop was unstable. I started
using the time domain response to check for
the stability of loops now. I have been able |
 |
10884
|
Fri Jan 9 14:13:02 2015 |
manasa | Update | General | ALS noise at ~30Hz | Before starting to move things around the
PSL table, I measured the ALS out of loop noise |
 |
9836
|
Mon Apr 21 22:53:16 2014 |
manasa | Update | LSC | ALS noise |
|
 |
8738
|
Mon Jun 24 16:06:17 2013 |
Manasa | Summary | Green Locking | ALS model | I am working on the basic
ALS servo model. The simulink model for the
same is attached. The loop is not yet complete |
|
8659
|
Thu May 30 18:29:21 2013 |
Manasa | Update | General | ALS medm screens edited | Renaming of the c1gcv model earlier (elog
7011) had left white boxes in most of |
|
9649
|
Tue Feb 18 23:55:33 2014 |
Jenne | Update | LSC | ALS locked with LSC! | I'm really excited, so I'm posting this,
even though I'm still working:
|
|