ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
|
15328
|
Tue May 12 22:47:49 2020 |
gautam | Update | LSC | Relative importance of losses in the arm and PRC | Yes, \eta_A is the (average) round-trip
loss for an arm cavity. I'd estimate
this is ~100ppm currently. I edited the original |
|
|
15329
|
Wed May 13 15:13:11 2020 |
Yehonathan | Update | Loss Measurement | 40m Phase maps loss estimation | Koji pointed out during the group meeting
that I should compensate for local tilt when
I move the beam around the mirror for calculating |
|
|
15330
|
Thu May 14 00:21:03 2020 |
gautam | Update | LSC | CM board boosts | Summary:
I think the boosts that are currently
stuffed on the CM board are too |
|
|
15331
|
Thu May 14 00:47:55 2020 |
gautam | Summary | Computer Scripts / Programs | pcdev1 added to authorized keys on nodus | This is to facilitate the summary page
config fines to be pulled from nodus in a
scripted way, without being asked for authentication. |
|
|
15332
|
Thu May 14 12:21:56 2020 |
Yehonathan | Update | Loss Measurement | 40m Phase maps loss estimation | I finished calculating the X Arm loss using
first-order perturbation theory. I will post
the details of the calculation later. |
|
|
15333
|
Thu May 14 19:00:43 2020 |
Yehonathan | Update | Loss Measurement | 40m Phase maps loss estimation | Perturbation theory:
The cavity modes |
|
|
15334
|
Fri May 15 09:18:04 2020 |
Jon | Update | BHD | BHD telescope designs accounting for ASC | Hang and I have reanalyzed the BHD telescope
designs, with the goal of identifying
sufficiently non-degenerate locations for |
|
|
15335
|
Fri May 15 19:10:42 2020 |
gautam | Update | SUS | All watchdogs tripped, now restored | This
EQ in Nevada seems to have tripped all watchdogs.
ITMX was stuck. It was released, and all |
|
|
15336
|
Mon May 18 18:00:16 2020 |
Hang | Update | BHD | BHD mode-matching study | [Jon, Tega, Hang]
We proposed a few BHD mode-matching telescope
designs and then preformed a few monte-carlo |
|
|
15337
|
Tue May 19 15:24:06 2020 |
rana | Update | BHD | BHD mode-matching study | It would be good to have a corner
plot with all the distances/ RoCs. Also
perhaps a Jacobian |
|
|
15338
|
Tue May 19 15:39:04 2020 |
Yehonathan | Update | Loss Measurement | 40m Phase maps loss estimation | I have a serious concern about this low
angle scattering analysis:
Phase maps perturb the spatial |
|
|
15339
|
Wed May 20 18:45:22 2020 |
Hang | Update | BHD | BHD mode-matching study--corner plot & adjustment requirement | As Rana suggested, we present the
scattering plot of the AS path
mode matching for various variables. |
|
|
15340
|
Wed May 20 19:34:58 2020 |
Koji | Update | General | ITM spares and New PR3 mirrors transported to Downs for phasemap measurement | Two ITM spares (ITMU01/ITMU02) and five
new PR3 mirrors (E1800089 Rev 7-1~Rev7-5)
were transported to Downs for phasemap measurement |
|
|
15341
|
Wed May 20 20:10:34 2020 |
rana, John Z | Update | Computer Scripts / Programs | NDS2 server / conf updated - seems OK now | We noticed about a week ago that
the NDS2 channel lists were not getting updated
on megatron. JZ and I investigated; he was |
|
|
15342
|
Thu May 21 15:31:26 2020 |
gautam | Update | Computer Scripts / Programs | NDS2 service restarted | The service had failed at 16:09
yesterday. I just restarted it and am now
able to fetch data again. |
|
|
15343
|
Fri May 22 01:43:18 2020 |
gautam | Update | Electronics | RF electronics trouble | To test a hypothesis, I have left the PSL
shutter closed. I notice significant glitches
in the dark electronics offsets on all the |
|
|
15344
|
Fri May 22 10:14:47 2020 |
Jordan | Update | General | Nitrogen Replacement | I was in the lab for Clean and Bake activities
and I replaced an empty N2 tank. Left tank
is at 2600 psi right tank at ~1300 psi. |
|
|
15345
|
Fri May 22 10:37:41 2020 |
rana | Update | Computer Scripts / Programs | NDS2 service restarted | was dead again this morning - JZ
notified
current restart instructions (after |
|
|
15346
|
Mon May 25 10:54:41 2020 |
rana | Update | Computer Scripts / Programs | NDS2 service restarted | so far it has run through the weekend with
no problems (except that there are huge log
files as usual). |
|
|
15347
|
Tue May 26 01:58:57 2020 |
gautam | Update | Electronics | Some electronics thoughts | A big factor in how much IFO locking activities
can take place is how cooperative the IMC
is. |
|
|
15348
|
Tue May 26 02:15:36 2020 |
gautam | Update | LSC | Lock acquisition portal entry | Summary:
Provided the IMC
is cooperative, the input pointing isn't |
|
|
15349
|
Tue May 26 02:31:00 2020 |
gautam | Update | LSC | Lock acquisition sequence | Here, I provide some details of the sequence.
Obviously, I am presenting one of the quickest
transitions to the fully locked state, I |
|
|
15350
|
Tue May 26 02:37:19 2020 |
gautam | Update | LSC | DARM loop measurement and fitting | Summary:
In order to estimate the free-running
DARM displacement noise, I measured the DARM |
|
|
15351
|
Tue May 26 03:01:35 2020 |
gautam | Update | LSC | CARM loop | Summary:
I am able to realize ~8
kHz UGF with ~60 degrees |
|
|
15352
|
Tue May 26 03:06:59 2020 |
gautam | Update | LSC | PRFPMI sensing matrix | Summary:
The response of the PRFPMI length
degrees of freedom as measured in the LSC |
|
|
15353
|
Tue May 26 03:26:58 2020 |
gautam | Update | LSC | Preliminary noise budget | Summary:
This isn't meant to be a serious
budget, mainly it was to force myself to |
|
|
15354
|
Tue May 26 10:04:54 2020 |
Jordan | Update | General | N2 Replacement | Replaced empty N2 tank, left tank at ~2000
psi, right tank ~2600 psi. |
|
|
15355
|
Tue May 26 14:32:44 2020 |
gautam | Update | LSC | Arm transmission RIN | Summary:
The measured RIN of the arm cavity
transmission when the PRFPMI is locked is |
|
|
15356
|
Tue May 26 16:00:06 2020 |
gautam | Update | LSC | Power buildup diagnostics | Summary:
I looked at some DC signals for
the buildup of the carrier and sideband fields |
|
|
15357
|
Tue May 26 19:19:30 2020 |
Hang | Update | BHD | BHD MM-- effects of astigmatism | Please see the attached doc.
I think the conclusion is that
if the AS1 RoC error is not significantly |
|
|
15358
|
Wed May 27 17:41:57 2020 |
Koji | Update | LSC | Power buildup diagnostics | This is very interesting. Do you have the
ASDC vs PRG (~ TRXor TRY) plot? That gives
you insight on what is the cause of the low |
|
|
15359
|
Wed May 27 19:36:33 2020 |
Koji | Update | LSC | Arm transmission RIN | My speculation for the worse RIN is:
- Unoptimized alignment -> Larger
linear coupling of the RIN with the misalignment |
|
|
15360
|
Wed May 27 20:14:51 2020 |
Koji | Update | LSC | Lock acquisition sequence | I see. At the 40m, we have the direct transition
from ALS to RF. But it's hard to compare
them as the storage time is very different. |
|
|
15361
|
Thu May 28 18:36:45 2020 |
gautam | Update | LSC | Arm transmission RIN | I agree, I think the PRC excess angular
motion, PIT
in particular, is a dominant |
|
|
15362
|
Fri May 29 00:34:57 2020 |
rana | Update | LSC | Arm transmission RIN | how bout corner plot with power signals
and oplevs? I think that would show not just
linear couplings (like your coherence), but |
|
|
15363
|
Tue Jun 2 14:05:24 2020 |
Hang | Update | BHD | MM telescope actuation range requirments | We computed the required actuation range
for the telescope design in elog:15357. The result |
|
|
15364
|
Wed Jun 3 01:34:53 2020 |
gautam | Update | LSC | Lock acquisition update portal | Highlights:
With better ASC servos
implemented, I think the lock stability has |
|
|
15365
|
Wed Jun 3 01:40:13 2020 |
gautam | Update | Electronics | More electronics woes | There were many locklosses from the point
where the arm powers were somewhat stabilized.
|
|
|
15366
|
Wed Jun 3 01:46:14 2020 |
gautam | Update | LSC | CARM loop | Summary:
The CARM loop now has a UGF of
~12 kHz with a phase |
|
|
15367
|
Wed Jun 3 02:08:00 2020 |
gautam | Update | LSC | Power buildup diagnostics | Attachments
#1 and |
|
|
15368
|
Wed Jun 3 02:14:32 2020 |
gautam | Update | ASC | PRC ASC improves arm transmission RIN | Summary:
I implemented an ASC servo for
the PRC, with the POP QPD as a sensor, and |
|
|
15369
|
Wed Jun 3 03:29:26 2020 |
Koji | Update | LSC | Lock acquisition update portal | Woo
hoo!
Which 1f signals are
you going to use? PRCL has sign flipping |
|
|
15370
|
Wed Jun 3 11:20:19 2020 |
gautam | Update | DetChar | Summary pages | Summary:
The 40m
summary pages have been revived. I've |
|
|
15371
|
Wed Jun 3 11:40:56 2020 |
gautam | Update | LSC | Lock acquisition update portal | For these initial attempts, I was just
trying to transition MICH to REFL55Q. I agree,
the PRCL situation may be more complicated. |
|
|
15372
|
Wed Jun 3 18:49:47 2020 |
gautam | Update | LSC | PRG and CARM signal sign | Summary:
I am inclined to believe that the
arm cavity losses are such that the |
|
|
15373
|
Wed Jun 3 19:19:11 2020 |
gautam | Update | SUS | All watchdogs tripped | This
EQ seems to have knocked all suspensions
out. ITMX was stuck. It is now released, |
|
|
15374
|
Thu Jun 4 00:21:28 2020 |
Koji | Summary | COC | ITM spares and New PR3 mirrors transported to Downs for phasemap measurement | GariLynn worked on the measurement of E1800089
mirrros.
|
|
|
15375
|
Thu Jun 4 08:45:41 2020 |
Jordan | Update | General | Presence at 40m | I will be at the 40m, in the Clean and
bake lab today from ~9am to ~3pm. |
|
|
15376
|
Thu Jun 4 20:54:40 2020 |
gautam | Update | SUS | MC1 Slow Bias issues | Summary:
I found that there is an issue with
the MC1 slow bias voltages. |
|
|
15377
|
Thu Jun 4 21:32:00 2020 |
Koji | Update | SUS | MC1 Slow Bias issues | We can limit the EPICS values giving some
parameters to the channels. cf https://epics.anl.gov/tech-talk/2012/msg00147.php
But this does not solve the MC1 |
|