| ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
|
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.
|
|
|
130
|
Tue Sep 27 15:10:59 2016 |
Gabriele | General | Measurements | Ring-down of etched disk | Quiet (roughing pump off, lights off):
60 seconds from
PDT: 2016-09-27 15:05:30.805667 PDT |
|
|
129
|
Tue Sep 27 14:54:53 2016 |
Gabriele | Electronics | Configuration | Epics values now saved to frames | Apparently, there was a mismatch in the
configuration, and DAQD was adding a wonderful
16 Hz comb all over the spectrum. |
|
|
128
|
Tue Sep 27 08:53:46 2016 |
Gabriele | General | Vacuum | Etched disk installed | Installed the etched disk: using manually
the centering ring allowed me to get the
beam on the QPD. A couple of taps to the |
|
|
127
|
Mon Sep 26 15:59:09 2016 |
Gabriele | Optics | Daily Progress | QPD auto centering | We have a few motorized mounts (with New
Focus picomotors) and one controller (an
old New Focus 8753, six axis total) that |
|
|
126
|
Mon Sep 26 15:54:01 2016 |
Gabriele | Facility | Configuration | Moved vacuum controllers | I moved the turbo pump controller out of
the clean room. Also, I installed the gauge
controller on the Cymac rack. |
|
|
125
|
Fri Sep 23 08:33:39 2016 |
Gabriele | Electronics | Configuration | Epics values now saved to frames | Now EPICS values are saved to frames, but
they are all zero! I noticed that we always
had the same problems with the cymac2 too. |
|
|
124
|
Fri Sep 23 08:11:48 2016 |
Gabriele | Mechanics | Daily Progress | Test of the disk retaining ring motion | In brief, it doesn't work. The magnets
and coils are strong enough to push up the
ring with a sample inside, but the friction |
|
|
123
|
Thu Sep 22 15:00:49 2016 |
Gabriele | Electronics | Configuration | Epics values now saved to frames | I was looking at some past trend data and
discovered that EPICS values were not written
to the frames. I added the following two |
|
|
122
|
Thu Sep 22 13:39:40 2016 |
Gabriele | Optics | Configuration | Updated design for the new C.Ri.Me. setup | Today I measured the amount of space available
on the table for the new (4-fold) C.Ri.Me.
setup. It's 1050 x 1220 mm, with the |
|
|
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 |
|
|
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 |
|
|
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 |
|
|
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 |
|
|
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. |
|
|
116
|
Tue Sep 20 15:34:00 2016 |
Gabriele | Optics | Daily Progress | Improved optical lever layout | Goal
Improve the optical setup,
by increasing the response of the QPD to
disk motion. |
|
|
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. |
|
|
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: |
|
|
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 |
|
|
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: |
|
|
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 |
|
|
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 |
|
|
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. |
|
|
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 |
|
|
107
|
Mon Sep 12 16:00:06 2016 |
Gabriele | General | Daily Progress | First fully automated measurements of ring down | I finished the first version of the automation
software to measure the ring down of the
disk modes. I tested it with the new substrate |
|
|
106
|
Sun Sep 11 10:05:33 2016 |
Gabriele | General | Daily Progress | New substrate in the chamber | I installed one of the new substrates (with
flats) into the chamber, and started the
pumpdown at about 9:45am LT. |
|
|
105
|
Thu Sep 1 02:13:33 2016 |
Gabriele | Optics | Characterization | Expected frequencies for the 75 mm disks with flats | Here are the nominal parameters of the
disk with flats
|
|
|
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 |
|
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 |
|
|
102
|
Tue Aug 23 08:46:04 2016 |
Gabriele | General | Daily Progress | Daily tests | MO03 - edge polished:
Turbo off, QPD centered, before
excitation (60 seconds) |
|
|
101
|
Mon Aug 22 16:59:13 2016 |
Gabriele, Alastair | Optics | Daily Progress | Laser polishing of the disk edges | We set up a test facility for laser polishing
the disk edges, using the CO2 laser in the
TCS laboratory. We focused the beam with |
|
|
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, |
|
|
99
|
Mon Aug 22 08:29:24 2016 |
Gabriele | General | Daily Progress | New test | Restarted roughing and turbo pump at about
8:10am.
|
|
|
98
|
Sun Aug 21 17:41:34 2016 |
Gabriele | General | Daily Progress | New test | I checked the status at about 5:20pm, the
turbo pump was in error and spinning down,
since the roughing pump has been off for |
|
|
97
|
Sun Aug 21 17:16:03 2016 |
Gabriele | General | Daily Progress | Ring down measurement with new disk | After fixing the setup, the measurement
with the new disk looks great. After more
than one hour the first two modes are still |
22x |
|
96
|
Sun Aug 21 15:36:16 2016 |
Gabriele | General | Daily Progress | New test | Roughing pump stopped at about 3:30:30pm.
HV amplifier on at 3:33:30pm, excitation
at 3:35:30pm. Recentered QPD at 3:36pm |
|
|
95
|
Sun Aug 21 13:45:56 2016 |
Gabriele | Optics | Daily Progress | Wierd behavior of ring downs and Improved setup | The last two ring downs I measured today
showed a weird behavior of the lowest modes:
|
|
|
94
|
Sun Aug 21 08:51:22 2016 |
Gabriele | General | Daily Progress | New disk installed | Vented the chamber. Installed a new disk
(MO 03). The one I measured yesterday is
now named MO 02 and it is the one with the |
|
|
93
|
Sat Aug 20 22:18:26 2016 |
Gabriele | General | Daily Progress | First measured Qs | Using the first ring down of the day (GPS 1155754513
+ 3600 seconds), I computed the amplitude
of each of the modes already identified, |
22x |
|
92
|
Sat Aug 20 17:01:10 2016 |
Gabriele | General | Daily Progress | First ring down measurements | Everything is working pretty well. This
morning the pressure was about 1.2e-6 Torr.
I connected the high voltage amplifier and |
|
|
91
|
Fri Aug 19 19:05:01 2016 |
Gabriele | Optics | Daily Progress | Disk installed into the chamber | I assembled the disk suspension sytem and
installed into the chamber. Although I don't
have the magnets and coils, I installed the |
10x |
|
90
|
Fri Aug 19 13:46:55 2016 |
Alena, Calum, Jon, Liz, Steve, Gabriele | Facility | Daily Progress | Clean room and vacuum complete | This morning we installed the clean room
curtains and washed them. It turns out that
the air filters are supposed to be powered |
|
|
89
|
Thu Aug 18 18:15:18 2016 |
Gabriele, Alena | Clean | Daily Progress | Clean room construction progress | Ceiling, back and side panels are installed.
The air filters have been cabled and connected
to the power supply. |
|
|
88
|
Wed Aug 17 16:41:05 2016 |
Gabriele, Alena | Clean | Daily Progress | Clean room construction progress | The clean room frame is built and secured
to the floor and wall. Panels are being installed
on the ceiling and back. Also, the optical |
|
|
87
|
Tue Aug 16 11:57:03 2016 |
Gabriele | Electronics | Configuration | Fixed cymac3 network and time issue | The cymac3 internal clock was off by about
10 seconds. When I tried to start the NTP
service, I found out that the cymac3 couldn't |
|
|
86
|
Tue Aug 16 11:53:30 2016 |
Alena, Gabriele | Clean | Daily Progress | Clean room progress | Some progress on the cleam room: bar fixed
to the wall, some more structure built, filters
in place. We had to (literally) work around |
|
|
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 |
|
|
84
|
Sun Aug 14 18:13:52 2016 |
Gabriele | Electronics | Daily Progress | Progress on the user interface | Some progress on writing the user interface:
|
|
|
83
|
Sun Aug 14 11:40:29 2016 |
Gabriele | Electronics | Daily Progress | Some python code | Today I wrote some auxiliary functions
that will be useful for the measurement system:
noise.py: set of functions |
|
|
82
|
Sat Aug 13 14:05:02 2016 |
Gabriele | General | Daily Progress | First work on the measurement user interface | Today I started programming part of the
user interface that will be used to perform
the measurements. Not much implemented so |
|