ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
15611
|
Mon Oct 5 00:37:19 2020 |
gautam | Update | BHD | Single bounce interferometer locked | Summary:
The simple interferometer, composed
of a single bounce reflection from ITMY and |
   |
15610
|
Sun Oct 4 15:32:21 2020 |
gautam | Update | SUS | Suspension health check | Summary:
After the earthquake on September
19 2020, it looks to me like the only |
 |
15609
|
Sat Oct 3 16:51:27 2020 |
gautam | Update | CDS | RFM errors | Attachment
#1 shows that the |
 |
15608
|
Fri Oct 2 12:52:22 2020 |
gautam | Update | General | Spectroscopic grade Isopropanol delivered | 2x500 ml bottles of spectroscopic grade
isopropanol were delivered. I marked them
with today's date and placed them in |
|
15607
|
Fri Oct 2 10:29:49 2020 |
gautam | Update | Optical Levers | ETMY, BS and ITMX HeNes degrading | Attachment
#1 shows that the |
|
15606
|
Thu Oct 1 17:44:48 2020 |
gautam | Update | General | Some inventory notes | The optomechanics stock in the lab was
in a sad state. We have obtained the following
from Thorlabs in the last two months: |
|
15605
|
Wed Sep 30 19:45:56 2020 |
rana | Update | General | HEPA blower startup capacitor replacement | it would be a good idea for us to have
an auto-reminder to have us check the flow
of all the HEPAs in the lab and elog it once |
|
15604
|
Wed Sep 30 17:12:24 2020 |
gautam | Update | General | HEPA blower startup capacitor replacement | [JV, GV]
The HEPAs work again. After running |
|
15603
|
Tue Sep 29 17:07:25 2020 |
gautam | Update | General | Lab visit for inventory location | I was in the lab from 1630-1830. I have located
and visually inspected all the parts required
for the magnet regluing / optic cleaning |
|
15602
|
Wed Sep 23 15:06:54 2020 |
Jordan | Update | VAC | TP2 Forepump Re-install | I removed the forepump to TP2 this morning
after the vacuum failure, and tested in the
C&B lab. I pumped down on a small volume |
 |
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 |
 |
15600
|
Wed Sep 23 10:06:52 2020 |
Koji | Update | VAC | TP2 running HOT | Here is the timeline. This suggests TP2
backing RP failure.
1st line: TP2 foreline pressure |
|
15599
|
Wed Sep 23 08:57:18 2020 |
gautam | Update | VAC | TP2 running HOT | The interlocks tripped at ~630am local
time. Jordan reported that TP2 was supposedly
running at 52 C (!). |
|
15598
|
Tue Sep 22 23:17:51 2020 |
Koji | Update | General | HEPA Inspection | Dimensions / Specs
- HEPA unit dimentions
- HEPA unit manufacturer |
6x |
15597
|
Tue Sep 22 23:16:54 2020 |
Koji | Update | General | HEPA Inspection | Gautam reported that the PSL HEPA stopped
running (ELOG
15592). So I came in today and started |
11x |
15596
|
Tue Sep 22 22:38:11 2020 |
gautam | Update | BHD | Sensing scheme for homodyne phase - some analytic calcs | I got some feedback from Koji who pointed
out that the phase tracker is not required
here. This situation is similar to the phase |
|
15595
|
Tue Sep 22 16:29:30 2020 |
Koji | Update | General | Control Room AC setting for continuous running | I came to the lab. The control room AC
was off -> Now it is on.
Here is the setting of the AC meant |
|
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. |
|
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. |
 |
15592
|
Mon Sep 21 16:40:52 2020 |
gautam | Update | PSL | HEPAs are no longer running | The HEPA filters on the PSL enclosure are
no longer running. I tried cycling the power
switch on the NW corner of the enclosure, |
|
15591
|
Mon Sep 21 15:57:08 2020 |
Jordan | Update | VAC | TP3 Forepump Replacement and Vac reset | I removed the forepump (Varian SH-110)
for TP3 today to see why it had failed over
the weekend. I tested it in the C&B lab |
  |
15590
|
Mon Sep 21 12:40:58 2020 |
gautam | Update | General | Workable IFO recovery | See Attachment
#1. |
 |
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 |
|
15588
|
Sun Sep 20 11:41:54 2020 |
gautam | Update | General | IMC re-locked | While I stopped by the lab this morning
to pick up some things, I took the opportunity
to continue the recovery. |
|
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 |
    |
15586
|
Sat Sep 19 19:37:16 2020 |
not Koji | Update | VAC | TP3 RP failure | Disconcerting because those tip seals were
just replaced [15417].
Maybe they were just defective, but if there |
|
15585
|
Sat Sep 19 19:14:59 2020 |
Koji | Update | General | ITMX released / ETMY UR magnet knocked off | There were two SUSs which didn't look
normal.
- ITMX was easily released by the |
|
15584
|
Sat Sep 19 18:46:48 2020 |
Koji | Update | General | Hand soap | I supplied a bottle of hand soap. Don't
put water in the bottle to dilute it as it
makes the soap vulnarable for cotamination. |
|
15583
|
Sat Sep 19 18:08:34 2020 |
rana | Update | General | M4.5 EQ in LA | the EQ was ~14 km south of Caltech and
17 km deep
|
|
15582
|
Sat Sep 19 18:07:35 2020 |
Koji | Update | VAC | TP3 RP failure | I came to the campus and Gautam notified
that he just had received the alert from
the vac watchdog. |
 |
15581
|
Sat Sep 19 11:27:04 2020 |
rana | Update | General | M4.5 EQ in LA | the seismometers obviously saturated during
the EQ, but the accelerometers captured some
of it. It looks like there's different |
|
15580
|
Sat Sep 19 01:49:52 2020 |
Koji | Update | General | M4.5 EQ in LA | M4.5 EQ in LA 2020-09-19 06:38:46 (UTC)
/ -1d 23:38:46 (PDT) https://earthquake.usgs.gov/earthquakes/eventpage/ci38695658/executive
I only checked the watchdogs. All |
|
15579
|
Fri Sep 18 10:47:48 2020 |
gautam | Update | BHD | Sensing scheme for homodyne phase | eSummary:
I |
 |
15578
|
Wed Sep 16 17:44:27 2020 |
gautam | Update | CDS | All vertex FE models restarted | I had to make a CDS change to the c1lsc
model in an effort to get a few more signals
into the models. Rather than risk requiring |
|
15577
|
Wed Sep 16 12:03:07 2020 |
Jon | Update | VAC | Replacing pressure gauges | Assembled is the list of dead pressure
gauges. Their locations are also circled
in Attachment 1. |
|
15576
|
Wed Sep 16 09:43:41 2020 |
gautam | Update | IOO | MC F spectrum | This
elog suggests that there is uniformly
1 stage engaged across all channels. I didn't |
|
15575
|
Tue Sep 15 22:11:52 2020 |
gautam | Update | BHD | More notes on the RF44 scheme | Summary:
After more trials, I |
|
15574
|
Tue Sep 15 19:17:30 2020 |
rana | Update | IOO | MC F spectrum | that's a very curious disconnection
the "Pentek" whitening
board that carries the MC channels has jumpers |
|
15573
|
Tue Sep 15 17:19:09 2020 |
gautam | Update | IOO | MC F spectrum | There was an abrupt change in the MC_F
spectrum between August
4 and August |
|
15572
|
Tue Sep 15 17:04:43 2020 |
gautam | Update | Electronics | DC adaptors delivered | These were delivered to the 40m today and
are on Rana's desk
|
|
15571
|
Tue Sep 15 12:20:36 2020 |
gautam | Update | Electronics | SR785 repaired | The unit was repaired and returned to the
40m. Now, with a DMM, I measure a DC offset
value that is ~1% of the AC signal amplitude. |
|
15570
|
Tue Sep 15 10:57:30 2020 |
gautam | Update | PSL | PMC re-locked, RGA re-enabled | The PMC has been unlocked since September
11 sometime (summary pages are flaky again).
I re-locked it just now. I didn't mess |
|
15569
|
Mon Sep 14 07:50:01 2020 |
Yehonathan | Update | BHD | Monte Carlo Simulations | Turns out what was causing the instability
in the aLIGO plots were the lock
commands which I forgot to remove before |
10x |
15568
|
Thu Sep 10 15:56:08 2020 |
Koji | Update | General | HEPA & Particle Level Status | 15:30
- PSL HEPA was running
at 33% and |
|
15567
|
Thu Sep 10 15:43:22 2020 |
Jon | Update | BHD | Input noise spectra for A+ BHD modeling | As promised some time ago, I've
obtained input noise spectra from the sites calibrated
to physical units. They are located in a |
|
15566
|
Wed Sep 9 20:52:45 2020 |
rana | Summary | IOO | wandering line in IMC | since the summary pages are working again,
I was clicking through and noticed that there's
a wandering peak in the whitened IMC spectrogram |
|
15565
|
Wed Sep 9 00:05:18 2020 |
gautam | Update | BHD | More notes on the RF44 scheme | Summary:
With the Michelson locked
on a dark fringe, the f2-f1 signal at ~44 |
   |
15564
|
Tue Sep 8 11:49:04 2020 |
gautam | Update | CDS | Some path changes | I edited /diskless/root.jessie/home/controls/.bashrc
so that I don't have to keep doing this |
|
15563
|
Tue Sep 8 01:31:43 2020 |
Koji | Update | BHD | A first look at RF44 scheme | - Loose fiber coupler: Sorry about that.
I could not detect something was loose there,
although some of the locks were not tightened. |
|
15562
|
Mon Sep 7 23:49:14 2020 |
gautam | Update | BHD | A first look at RF44 scheme | Summary:
Over the last couple of days, I've
been working towards getting the infrastructure |
|