| ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
|
284
|
Tue Jan 31 11:21:44 2017 |
Gabriele | Mechanics | Daily Progress | Retaining ring mechanics | All parts for the motion of the retaining
rings have been received and are ok. We're
going to clean and bake them. |
|
|
286
|
Tue Jan 31 16:55:17 2017 |
Gabriele | General | Daily Progress | Improved autocenter, excitation not working, wandering line | The autocenter script wasn't working
in a very robust way (sometimes the socket
connection to the controller failed, some |
|
|
288
|
Wed Feb 1 15:35:30 2017 |
Gabriele | General | Daily Progress | excitation not working - FIXED | My bad, a cable was disconnected.
|
|
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291
|
Mon Feb 6 11:19:13 2017 |
Gabriele | Optics | Daily Progress | Laser swap | The Thorlabs laser has been misbehaving
for the whole weekend. Even after many days
being continuosly on, the wandering line |
|
|
295
|
Tue Feb 7 16:16:37 2017 |
Gabriele | Optics | Daily Progress | Lasers | The high power lasers I tested so far (the
Thorlabs 21mW and the JDSU 1125P) are noisy:
they both have wandering lines that from |
|
|
296
|
Wed Feb 8 17:01:01 2017 |
Gabriele | Optics | Daily Progress | Two laser installed, setup aligned | Today I swapped out the 8mW laser
and installed two 2.5 mW lasers. I rebuilt
the input part of the optical levers and |
|
|
300
|
Thu Feb 9 09:30:52 2017 |
Gabriele | Optics | Daily Progress | Two laser installed, setup aligned | The lasers are behaving well, there is
no high noise or wandering lines. The spectrum
below is taken in air: that explains the |
|
|
303
|
Fri Feb 10 17:16:28 2017 |
Gabriele | Mechanics | Daily Progress | Translation stage to move retaining rings | This afternoon I installed the picomotor
and the translation stage that will be used
to move the retaining rings up and down. |
|
|
304
|
Sat Feb 11 16:22:26 2017 |
Gabriele | Mechanics | Daily Progress | Translation stage to move retaining rings | The ring motion up and down was not very
smooth, again due to friction on the centering
pins. |
|
|
305
|
Tue Feb 14 10:55:13 2017 |
Gabriele | General | Daily Progress | Something fishy with bay 4 of the new setup | I did two set of measurements with the
new coated samples from Montreal. I reshuffled
the position in the two measurements. In |
|
|
311
|
Fri Feb 17 13:44:47 2017 |
Gabriele | Optics | Daily Progress | Swapped picomotor and re-alignment | Since I had recurrent problems with the
picomotors used for QPD3, I swapped them
with another Newport motorized mirror that |
|
|
331
|
Fri Mar 10 16:44:13 2017 |
Gabriele | Optics | Daily Progress | Updated in vacuum periscope of CR0 | This afternoon I removed the old periscope
from CR0 and installed a new one with finely
adjustable mount, like those in the new chamber. |
|
|
338
|
Fri Apr 7 16:19:03 2017 |
Gabriele | Optics | Daily Progress | New 1103P laser installed | This afternoon I installed the new Lumentum
(former JDSU) HeNe laser, model 1103P in
CR0. |
|
|
11
|
Fri May 6 14:20:43 2016 |
Gabriele | Electronics | Design | Design of optical lever electronics | For the optical levers we are going to
use the same QPD that are used in aLIGO optical
levers (see T1600085 and |
|
|
12
|
Sun May 8 13:35:04 2016 |
rana | Electronics | Design | Design of optical lever electronics | Koji, Rich, and I recently came up with
a new QPD design which is better for general
lab use than the aLIGO ones (which have a |
|
|
13
|
Tue May 10 13:32:17 2016 |
Gabriele | Electronics | Design | Design of optical lever electronics | After a very useful discussion with Rich
this morning, I think the circuit based on
aLIGO optical levers design should be good |
|
|
14
|
Thu May 19 11:33:44 2016 |
Gabriele | Electronics | Design | Optical lever electronics design | The circuit design sent out for fabrication
is available in the DCC: D1600196 |
|
|
15
|
Thu May 19 11:36:04 2016 |
Gabriele | Mechanics | Design | A first design of the disk assembly | Here are some screenshots of the disk assembly
and a look at how four of them will sit into
the vacuum chamber. The Solidworks models |
|
|
16
|
Fri May 20 15:18:58 2016 |
Gabriele | Optics | Design | Optical levers layout | Attached a first layout of the optical
lever systems. The beam spot radius on the
QPD is about 0.8 mm, and the lever arm length |
|
|
17
|
Sun May 22 23:40:45 2016 |
Gabriele | Optics | Design | Optical levers layout | An improved design is attached. I modified
the input telescope to avoid using shor focal
length lenses, to make it less critical, |
|
|
18
|
Thu May 26 02:51:27 2016 |
Gabriele | Electronics | Design | ESD design | A preliminary design of the ESD board is
available on the DCC: D1600214 |
|
|
132
|
Thu Sep 29 15:40:45 2016 |
Gabriele | Optics | Design | Beam profile of new 21mW HeNe laser and tweak of optical lever design | I measured the beam profile of the new
Thorlabs HeNe (21.8 mW measured). The beam
waist is 355 microns, very close to the laser |
|
|
266
|
Thu Jan 19 14:16:53 2017 |
Gabriele | Mechanics | Design | New concept for retaining ring motion | Since my experiment with coil and magnets
didn't work out very well, here's
a new concept for the motion of the four |
7x |
|
20
|
Mon Jun 6 13:35:36 2016 |
Gabriele | Electronics | General | Components | The PCBs for the QPD circuit and ADC interface
are here and look ok. All electronics components
are also here (except for the ADC connector |
|
|
21
|
Tue Jun 7 14:07:55 2016 |
Gabriele | Facility | General | Rack and workstation | I moved the unused rack from the Crackling
Noise lab to the C.Ri.Me lab. It will be
used for the new cymac. I also started putting |
|
|
57
|
Thu Jul 21 14:58:26 2016 |
Gabriele | Electronics | General | Glitches are of digital origin | So here's the final proof that the
glitches I see are digital:
There is a positive jump |
|
|
63
|
Wed Jul 27 08:59:12 2016 |
Gabriele | Electronics | General | Pressure now in torr | The old channel X3:CR1-PRESSURE_LOGTORR
does not exist anymore. The new channel is
now directly in torr and it is called X3:CR1-PRESSURE_TORR. |
|
|
65
|
Wed Jul 27 11:27:11 2016 |
Gabriele | Facility | General | Pumps stopped and venting | 11:25am LT: closed valve between roughing
and turbo pumps, switched off both pumps.
Turbo pump is slowing down |
|
|
74
|
Mon Aug 8 10:42:46 2016 |
Gabriele | General | General | Dependency of eigenmode frequencies on thickness and diameter | I ran a set of COMSOL simulations to determine
the dependency of the frequency of each eigenmode
on the disk thickness and diameter, within |
26x |
|
77
|
Thu Aug 11 08:45:19 2016 |
Gabriele | General | General | QPD signals with dielectric filter | I installed a dielectric laser line filter
(Thorlabs FLH05633-5, center wavelength 633
nm, FWHM 5 nm) in front of the QPD. In this |
|
|
85
|
Sun Aug 14 18:26:19 2016 |
Gabriele | General | General | Plans for the automatic mode search | Here's how I imagine the mode search
to proceed:
the user select the list |
|
|
100
|
Mon Aug 22 12:01:52 2016 |
Gabriele | General | General | Tests of the day | Disk excited at 12:01pm. Exited the room
at 12:03pm.
Opened the chamber at about 2:30pm, |
|
|
103
|
Tue Aug 23 09:21:25 2016 |
Gabriele | General | General | Status of Mark Optics disks | We initially received 20 disks (75 mm diameter,
1 mm thickness) from Mark Optics. Here's
their status as of today |
|
|
104
|
Tue Aug 23 09:44:11 2016 |
Gabriele | General | General | Measurements on MO-02 | Two good ring-downs measurements were performed
on MO-02. The first one was already reported
in a previous elog |
7x |
|
108
|
Tue Sep 13 10:33:35 2016 |
Gabriele | General | General | Disk excited | Disk excited with white uniform noise,
amplitude 5 V, for some tens of seconds.
Excitation off at |
|
|
109
|
Wed Sep 14 13:08:05 2016 |
Gabriele | General | General | Ringdown with roughing pump off | At 1:05pm LT I stopped the roughing pump
and started a ring-down measurement. Pump
restarted at 2:18pm LT. |
|
|
110
|
Wed Sep 14 20:17:33 2016 |
Gabriele | General | General | Band-limited excitation | Excitation started at 20:15:30LT, 20 seconds
long. The excitation is band-limited (10
Hz) centered around each of the predicted |
|
|
111
|
Thu Sep 15 08:13:20 2016 |
Gabriele | General | General | Pump had no effect on ring down measurements | The plot below shows three measurements
of the Q of the same disk: during the first
two the roughing pump was on, while during |
|
|
112
|
Thu Sep 15 08:27:57 2016 |
Gabriele | General | General | New band-limited excitation | Same as in elog #110,
but now the amplitude is proportional to
frequency squared: |
|
|
113
|
Thu Sep 15 11:23:13 2016 |
Gabriele | Facility | General | Chamber open | Turbo pump off and spinning down at 9:37am
LT. Pumo completely stopped at 11:15am LT
Openend the chamber and removed |
|
|
114
|
Thu Sep 15 15:15:10 2016 |
Gabriele | General | General | Edge effect on losses | I made a COMSOL model that can compute
the distribution of elastic energy for each
mode, dividing it into: |
|
|
115
|
Fri Sep 16 14:06:43 2016 |
Gabriele | General | General | Pump had no effect on ring down measurements | Same plot as below, but this time with
estimated 95% confidence intervals for the
Q values, as obtained from the fit only. |
|
|
117
|
Tue Sep 20 16:12:09 2016 |
Gabriele | General | General | Pump down | As a test, I installed MO1 (the disk with
the burn mark, used for the first edge laser
polishing test) and started pumping down. |
|
|
118
|
Tue Sep 20 16:43:58 2016 |
Gabriele | General | General | Excitation and ring down | The pressure is at abour 3e-6 Torr. I centered
the QPD and started an excitation. The HV
amplifier manual states that the driver can |
|
|
119
|
Wed Sep 21 08:12:13 2016 |
Gabriele | General | General | Excitation and ring down | New excitation (2000V) at about 8:06am.
Had to recenter the QPD again after the excitation.
Engaged the 500Hz high pass filter |
|
|
120
|
Wed Sep 21 14:42:47 2016 |
Gabriele | General | General | Serialized (etched) disk installed | Just for fun, I installed the disk thas
has been etched in the center with "1234".
I figured out that the ESD PCB was probably |
|
|
121
|
Thu Sep 22 09:49:21 2016 |
Gabriele | General | General | Ring-down of etched disk | QPD centerd, quiet data, light off, one
minute from
PDT: 2016-09-22 09:46:29.393609 |
|
|
131
|
Wed Sep 28 10:26:58 2016 |
rana | General | General | references on ideal glasses | Some easy to read reviews on
thin films and ideal glass for people getting
started in this Q measuring game.
|
|
|
149
|
Thu Oct 27 14:02:38 2016 |
Alena | General | General | Annealing | Annealing run (447-448) on 3" wafers
- Crime 10/27/2016 https://dcc.ligo.org/T1600485-v1
|
|
|
157
|
Fri Nov 4 08:13:25 2016 |
Gabriele | Electronics | General | Power outage? | This morning I found the cymac and the
workstation rebooted, so I suspected a power
cut in the last days. However, the function |
|