ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
11623
|
Fri Sep 18 19:19:49 2015 |
rana | Frogs | Computer Scripts / Programs | remote data access: volume 1, Inferno | NDS2 restarted after hours long upgrade
process; testing has begun. Let's try
to get some long stretches of MC locked with |
|
11624
|
Mon Sep 21 00:51:36 2015 |
rana | Update | General | op340m, autoburt cron =? megatron | I modified the perl script which does our
hourly autoburt so that it can run on megatron
instead of op340m (old Solaris machine). |
|
11631
|
Tue Sep 22 02:11:17 2015 |
rana | Summary | Computer Scripts / Programs | Frequency counting algorithm | I was going to suggest using a software
PLL, but perhaps averaging gives the same
result. The same ADC signal can be fed to |
|
11646
|
Fri Sep 25 19:06:13 2015 |
rana | Update | SUS | ETMX IS drifting | I don't see any evidence of it getting
more stable. It seems there was a big step
in January, but the problem we were talking |
|
11649
|
Tue Sep 29 18:03:11 2015 |
rana | Update | LSC | use LISO | Use LISO - see what it tells you. I would
think that you should make a differential
RC filter to get the right behavior. (e.g. |
|
11675
|
Thu Oct 8 21:35:49 2015 |
rana | Update | LSC | DRFPMI Progress | Give us a lockloss or other kind of time
series plot so we can bask in the glory. |
|
11688
|
Wed Oct 14 15:59:06 2015 |
rana | Update | Computer Scripts / Programs | nodus web apache simlinks too soft | None of the links here seem to work. I
forgot what the story is with our special
apache redirect |
|
11696
|
Sat Oct 17 18:55:07 2015 |
rana | Update | LSC | DRFPMI Locked for 20 sec | in addition
to Koji's words I feel like we should |
|
11711
|
Fri Oct 23 21:58:10 2015 |
rana | Update | SUS | MC2 F2P mis-tuned | The OSEMs cannot be used for coil balancing
above ~10 Hz. The main coupling path from
OSEM drive to sensor is not through the mirror |
|
11752
|
Wed Nov 11 14:06:09 2015 |
rana | Update | SUS | ETMX oplev servo disabled | How many volts does it take to pitch the
ETM by 5 urad? |
|
11774
|
Tue Nov 17 15:59:23 2015 |
rana | Update | SUS | ITMX UL calmed? | Although this noise is bad, we have always
had these kind of humps around the bounce
mode. Our interpretation in the past was |
|
11784
|
Wed Nov 18 20:49:05 2015 |
rana | Update | Computer Scripts / Programs | nodus boot getting full | controls@nodus|~ > df -h
Filesystem
Size Used |
|
11787
|
Wed Nov 18 23:40:01 2015 |
rana | Update | Optical Levers | Calibration of oplevs for ITMY/ETMY | OMG. Please try to use larger fonts and
PDF so that we can read the plots.
|
|
11796
|
Sun Nov 22 07:09:01 2015 |
rana | Update | IOO | IMC fix | On the demod board there is a 10 dB attenuator
(AT1), which lowers the level to -10 dBm
before the ERA-5. Then it should be 10 dBm |
|
11807
|
Wed Nov 25 04:24:21 2015 |
rana | Update | IOO | LO level check for the IMC demod board | Hmmm. Very non-standard demod. From the
photo, looks like someone did some surgery
with the attenuators (AT1, AT2, AT3) in the |
|
11812
|
Wed Nov 25 20:07:35 2015 |
rana | Update | IOO | LO level check for the IMC demod board | Perhaps we can replace T1 with a mini-circuits
hybrid 0-90 deg splitter and then remove
the trim caps. (JSPQ-80, JYPQ-30, SCPQ-50) |
|
11821
|
Sun Nov 29 05:23:57 2015 |
rana | Update | LSC | Current state of the frequency source, and possible improvement | I need some more hints to understand the
improvement, although its generally good
to re-build it considering the sad state |
|
11842
|
Thu Dec 3 06:15:38 2015 |
rana | Update | Optical Levers | Calibration of oplevs for ITMX/ETMX | http://blogs.mathworks.com/loren/2007/12/11/making-pretty-graphs/
Let Loren help you make your Oplev
data readable to humans. |
|
11869
|
Wed Dec 9 23:16:13 2015 |
rana | Update | Computer Scripts / Programs | Nodus security | NDS2 and the usual ports so that we can
use optimus as a comsol server.
|
|
11892
|
Fri Dec 18 17:37:04 2015 |
rana | Update | LSC | Uncooperative AUX X | Here's how we should diagnose the EX
laser:
Compare IR RIN of laser |
|
11899
|
Wed Dec 23 03:27:04 2015 |
rana | Update | Computer Scripts / Programs | LHO EPICS slow down | https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=24321
This LHO log indicates that EPICS
slow down could be due to NFS activity. Could |
|
11900
|
Wed Dec 23 15:43:02 2015 |
rana | Summary | PSL | PMC FSS IMC RF summing box | The EOM upstream of the PMC is used as
the phase corrector for the FSS/IMC servo.
It is also used to apply the 35.5 MHz PDH |
|
11901
|
Wed Dec 23 16:15:47 2015 |
rana | Omnistructure | ALARM | fire alarm | Fire alarm went off several minutes ago.
Talked to security and they said there was
no fire. It beeped twice again just now. |
|
11910
|
Tue Jan 5 13:17:06 2016 |
rana | Update | LSC | AUX X Freq Noise attempt | The problem here is that the MC displacement
noise is leading to large frequency excursions
of the PSL beam. Options |
|
11913
|
Tue Jan 5 17:19:57 2016 |
rana | Update | safety | Rat trap locations | In the modern times, people use glue traps
to catch rats instead of springs. They are
less hazardous to people and don't spread |
|
11922
|
Fri Jan 8 20:02:49 2016 |
rana | Update | LSC | AUX Y Freq Noise measured | Unless this is the limit from the way you
guys set up the PLL, it seems like there's
no difference between the two lasers that's |
|
11934
|
Thu Jan 14 18:41:36 2016 |
rana | Update | WienerFiltering | Noise Subtraction Puzzler | Just not just pedagogical ! Freq
domain MISO coherence based subtraction estimation
is much faster than calculating MISO WF. |
|
11942
|
Thu Jan 21 18:34:04 2016 |
rana | Update | LSC | PSL and AUX-X temperatures changed | Is the black ref spectrum from this year
or from May of 2015 or ?
I wonder if the noise is a bunch |
|
11947
|
Fri Jan 22 18:46:03 2016 |
rana | Update | Green Locking | AUX-X AM/PM investigations | The PDA photodetectors are DC coupled,
so you cannot use them to go directly into
the analyzer. Must use the DC block so that |
|
11954
|
Wed Jan 27 20:51:00 2016 |
rana | Update | PEM | ETMX floor vs table noise | I didn't really appreciate this measurement
until just now. IF you can save the DTT .xml
file with all the traces in it (i.e. NOT |
|
11962
|
Fri Jan 29 16:55:27 2016 |
rana | Update | Green Locking | Innolight laser is 10 years old | I don't think there's any evidence
that the noise eater is bad. That would change
the behavior of the relaxation oscillation |
|
12022
|
Sat Mar 5 10:37:48 2016 |
rana | Update | IOO | PSL Laser Opened | Sorry, that was me; taking some photos
of the PSL and EX mirrors.
|
|
12027
|
Tue Mar 8 18:22:20 2016 |
rana | Update | Green Locking | Laser swap - some improvement | Why is the transmission of X green so low?
Perhaps you can phase lock the IR and then
scan the X frequency, using the X arm as |
|
12030
|
Thu Mar 10 16:32:45 2016 |
rana | Update | endtable upgrade | Inventory check | Its not a good idea to use green mounts
with green lasers. Steve should be able to
get another copy of the EY doubler mount |
|
12032
|
Sat Mar 12 22:23:37 2016 |
rana | Summary | IOO | PMC relocked | Found it locked on TEM01 mode.
Sweets in the fridge for non-PhD
holders, courtesy of the highest levels of |
|
12048
|
Fri Mar 25 23:54:04 2016 |
rana | Update | PEM | Guralp Seismometers | Something seems not right. The Guralp response
should be flat in velocity from 0.05-30 Hz.
Why is there any feature at 1 Hz? Saturation |
|
12092
|
Wed Apr 27 09:45:56 2016 |
rana | Update | SUS | spare SOS tower | Bah, we need ruby slippers for all future
suspensions. Prism with curved backside and
smooth grooves. |
|
12093
|
Wed Apr 27 14:06:31 2016 |
rana | Summary | General | meeting notes |
Gautam will get
help from Johannes and finish EX table by
Monday.
Steve |
|
12098
|
Thu Apr 28 18:53:05 2016 |
rana | Update | LSC | Green PDH demod lowpass | OK - but give us a circuit diagram and
the expected before/after loop plots. Got
to make sure we keep the right impedance |
|
12102
|
Mon May 2 17:06:58 2016 |
rana | Summary | COC | G&H optics to Fullerton/HWS for anneal testing | Steve sent 4 of our 1" diameter G&H
HR mirrors to Josh Smith at Fullerton for
scatter testing. Attached photo is our total |
|
12103
|
Mon May 2 17:11:55 2016 |
rana | Update | COC | RC folding mirrors | Antonio/Gautam
are now developing a more up to date Finesse
model of our recycling cavities to see what |
|
12108
|
Thu May 5 14:05:01 2016 |
rana | Update | endtable upgrade | ALS status update | All seems very fishy. Its not good to put
attenuators and filters in nilly-willy.
Once the post-PD bandpass |
|
12111
|
Fri May 6 19:08:52 2016 |
rana | Update | LSC | Green PDH demod lowpass | Seems weird to design a PD lowpass with
a corner at the modulation frequency. Recall
what our strategy is with the other photodetectors |
|
12113
|
Sun May 8 08:39:21 2016 |
rana | Update | LSC | Green PDH demod lowpass | Indeed. This is why the LSC PDs have a
2f notch in addition to the 1f resonance.
In recent versions, we also put a 2f notch |
|
12178
|
Tue Jun 14 16:53:16 2016 |
rana | Update | SUS | ETMX watch | What about ETMY? and are these really microradians
or just some made up cal? |
|
12193
|
Thu Jun 16 18:42:12 2016 |
rana | Update | COC | Contrast as a function of RoC of ETMX | That sounds weird. If the ETMY RoC |
|
12197
|
Mon Jun 20 01:38:04 2016 |
rana | Update | COC | Contrast as a function of RoC of ETMX | So, it seems that changing the ETMX for
one of the spares will change the contrast
defect from ~0.1% to 0.9%. True? Seems like |
|
12210
|
Wed Jun 22 08:40:42 2016 |
rana | Update | LSC | Y arm @ 30kHz UGF w/POY, AO | Below 100 Hz, I suppose this means that
the X arm is now limited by the quadrature
sum of the X and Y arm seismic noise. |
|
12214
|
Sun Jun 26 15:27:28 2016 |
rana | Frogs | IOO | PMC /MC lopced | Found PMC unlocked for many hours so I
relocked it. IMC relocked by itself, but
the input switch seems to be flickering to |
|
12245
|
Tue Jul 5 19:10:41 2016 |
rana | Update | General | Vent progress | I'd suggest clamping and moving it
to the flow bench so you can inspect with
a bright light. Then remove the wire and |
|