2018-01-30

50 mm fused silica disks from University Wafer

• 2:50pm in chamber
  • S1800515 in CR1
  • S1800516 in CR2
  • S1800517 in CR3
  • S1800518 in CR4
• 2:55pm roughing pump on
• 3:03pm turbo pump on
• Excitations:
  • Quiet time before excitation: 1201400855
    Excitation broadband: 1201400890
    Quiet time after excitation: 1201400915
  • Quiet time before excitation: 1201404545
    Excitation broadband: 1201404580
    Quiet time after excitation: 1201404605
  • Quiet time before excitation: 1201408236
    Excitation broadband: 1201408271
    Quiet time after excitation: 1201408296
  • Quiet time before excitation: 1201411926
    Excitation broadband: 1201411961
    Quiet time after excitation: 1201411986
  • Quiet time before excitation: 1201415616
    Excitation broadband: 1201415651
    Quiet time after excitation: 1201415676
  • Quiet time before excitation: 1201419306
    Excitation broadband: 1201419341
    Quiet time after excitation: 1201419366
  • Quiet time before excitation: 1201422996
    Excitation broadband: 1201423031
    Quiet time after excitation: 1201423056
  • Quiet time before excitation: 1201426686
    Excitation broadband: 1201426721
    Quiet time after excitation: 1201426746

2018-11-29

• In chamber
  • S1800515 in CR1
  • S1800516 in CR2
  • S1800519 in CR3
  • S1800520 in CR4
• roughing pump on 4:14pm
• turbo pump on 4:24pm >> actually forgot to switch one turbo pump!!!
• turbo pump on 2018-11-30 at 9:27am

2018-03-24

• 5:10pm in chamber
  • S1800515 in CR1
  • S1800519 in CR2
• 5:13pm roughing pump on
• 5:20pm turbo pump on

2020-01-24

• 3:15pm in chamber
  • S1800515 in CR1
  • S1800519 in CR2
• 3:16pm roughing pump on
• 3:26pm turbo pump on

2020-01-30

• 8:45 am in chamber
  • S1800515 in CR1
  • S1800519 in CR2
• 8:46 am roughing pump on
• 8:55 am turbo pump on

2018-05-01

• 16:10 pm in chamber
  • S1800516 in CR0
• 16:20 pm roughing pump on
• 16:40 pm turbo pump on

  2018-05-04

• 02:21 pm in chamber:
  • AK_01 in CR1
  • AK_03 in CR3
• 02:25 pm roughing pump on
• 02:44 pm turbo pump on

• 03:30 pm in chamber:
  • S1800516 in CR0
• 03: 35 pm roughing pump on
• 03:42 turbo pump on

2018-03-06

2 inches fused silica disks with a-Si coating

• 4:00pm in chamber
  • S1800516 in CR1
  • S1600520 in CR2
• 4:02pm roughing pump on
• 4:10pm turbo pump on

2018-02-28

2 inches fused silica disks with a-Si coating

• 2:10pm in chamber (not reverse order)
  • S1800519 in CR1
  • S1800515 in CR2
• 2:12pm roughing pump on
• 2:22pm turbo pump on
• Excitations
  • Quiet time before excitation: 1203905757
    Excitation broadband: 1203905792
    Quiet time after excitation: 1203905817
  • Quiet time before excitation: 1203909447
    Excitation broadband: 1203909482
    Quiet time after excitation: 1203909507
  • Quiet time before excitation: 1203913137
    Excitation broadband: 1203913172
    Quiet time after excitation: 1203913197
  • Quiet time before excitation: 1203916827
    Excitation broadband: 1203916862
    Quiet time after excitation: 1203916887
  • Quiet time before excitation: 1203920517
    Excitation broadband: 1203920552
    Quiet time after excitation: 1203920577
  • Quiet time before excitation: 1203924207
    Excitation broadband: 1203924242
    Quiet time after excitation: 1203924267
  • Quiet time before excitation: 1203927897
    Excitation broadband: 1203927932
    Quiet time after excitation: 1203927957
  • Quiet time before excitation: 1203931587
    Excitation broadband: 1203931622
    Quiet time after excitation: 1203931647
     

2018-01-31

50 mm fused silica disks from University Wafer

• 12:35pm in chamber
  • S1800519 in CR1
  • S1800520 in CR2
  • S1800521 in CR3
  • S1800522 in CR4
• 12:38pm roughing pump on
• 12:47pm turbo pump on
• Excitations
  • Quiet time before excitation: 1201477474
    Excitation broadband: 1201477509
    Quiet time after excitation: 1201477534
  • Quiet time before excitation: 1201481164
    Excitation broadband: 1201481199
    Quiet time after excitation: 1201481224
  • Quiet time before excitation: 1201484854
    Excitation broadband: 1201484889
    Quiet time after excitation: 1201484914
  • Quiet time before excitation: 1201488544
    Excitation broadband: 1201488579
    Quiet time after excitation: 1201488604
  • Quiet time before excitation: 1201492234
    Excitation broadband: 1201492270
    Quiet time after excitation: 1201492294
  • Quiet time before excitation: 1201495924
    Excitation broadband: 1201495959
    Quiet time after excitation: 1201495984
  • Quiet time before excitation: 1201499614
    Excitation broadband: 1201499649
    Quiet time after excitation: 1201499674
  • Quiet time before excitation: 1201503304
    Excitation broadband: 1201503339
    Quiet time after excitation: 1201503364
     

2018-05-02

• 10:05 am in chamber
  • S1800520 in CR0
• 10:06 am roughing pump on
• 10:20 am  turbo pump on

2018-05-02

• 17:37 added ND because QPD was oversaturated. Repeating the measurement without venting
  • S1800520 in CR0

• 01:41 pm in chamber
  • S1800520 in CR0
• 01:41 pm roughing pump on
• 01:59 pm turbo pump on

• 19:30 in chamber
  • S1800614 in CR1
  • S1800618 in CR2
  • S1600600 in CR4
• 19:40 roughing pump on
• 19:45 turbo pump on

Started a measurement for CR1 and CR2 only. CR4 is instaled, centered and ready to be measured later

Measurement for S1600600 started at 11:50am

• 11:01 in chamber
  • S1800614 in CR1
  • S1800618 in CR2
  • S1800619 in CR3
  • S1600600 in CR4
• 11:10 roughing pump on
• 11:20 turbo pump on

• 17:40 pm in chamber
  • S1800617 in CR0
• 17:45 roughing pump on
• 17:57 turbo pump on

• 16:20 in chamber
  • S1800618 in CR0
• 16:20 roughing pump on
• 16:30 turbo pump on

• 14:45 in chamber
  • S1800619 in CR0
• 14:45 roughing pump on
• 14:55 turbo pump on

• 14:41 in chamber
  • S1800620 in CR0
• 14:45 roughing pump on
• 14:54 turbo pump on

• 15:20 in chamber
  • S1800620 in CR0
• 15:30 roughing pump on
• 15:45 turbo pump on

2018-04-05

• 8:35am in chamber
  • S1800634 in CR2
• 8:39am roughing pump on
• 7:49pm turbo pump on

2018-04-07

• 9:10am in chamber
  • S1800634 in CR2
• 9:15am roughing pump on
• 9:25am turbo pump on

2018-04-09

• 3:30 pm in chamber
  • S1800634 in CR1
• 3:30 pm roughing pump on
• 3:45 pm turbo pump on

2018-04-12

• 8:30 am in chamber
  • S1800634 in CR1
• 8:35 am roughing pump on
• 8:45 pm turbo pump on

2018-04-14

• 6:40pm in chamber CR0
• 6:45pm roughing pump on
• 6:59pm turbo pump on

2018-12-07

• in chamber
  • S1800634 in CR1
• 9:26am roughing pump on
• 9:36am turbo pump on

2018-12-13

• S1812071 in chamber CR0
• roughing pump on at 12:42pm
• turbo pump on at 1:07pm

2018-12-20

• in chamber
  • S1812071 in CR0
• 4:52pm roughing pump on
• 5:18pm turbo pump on

2018-11-30

• in chamber
  • S1812071 in CR1
  • S1812072 in CR2
• roughing pump on 3:58pm
• turbo pump on 4:07pm

2019-01-30

• 9:58am in chamber
  • S1812072 in CR0
• 10:00am roughing pump on
• 10:25am turbo pump on

2019-02-12

• 08:45 am in chamber
  • S1900046 in CR1
  • S1900047 in CR2
  • S1900048 in CR3
  • S1900049 in CR4
• 08:57am roughing pump on
• 09:10am turbo pump on

2019-04-04

• 10:24 am in chamber
  • S1900046 in CR1
  • S1900047 in CR2
  • S1900048 in CR3
  • S1900049 in CR4
• 10:26am roughing pump on
• 10:35am turbo pump on

2019-02-12

• 09:05 am in chamber
  • S1900046 in CR1
  • S1900047 in CR2
  • S1900048 in CR3
  • S1900049 in CR4
• 09:07am roughing pump on
• 09:15am turbo pump on

2019-03-20

• 1:20 pm in chamber
  • S1900071 in CR1
  • S1900072 in CR2
• 1:36 pm roughing pump on
• 1:47 pm turbo pump on

2019-03-11

• 4:23pm in chamber
  • S1900072 in CR1
  • S1900071 in CR2
• 4:25pm roughing pump on
• 4:35pm turbo pump on

2019-03-25

• 8:20am in chamber CR0
• 8:22am roughing pump on
• 8:50am turbo pump on

2019-03-29

• 4:20pm in chamber CR0
• 4:23pm roughing pump on
• 4:45pm turbo pump on

2019-04-09

• 9:18 am in chamber
  • S1900198 in CR1
  • S1900199 in CR2
  • S1900200 in CR3
  • S1900201 in CR4
• 9:19am roughing pump on
• 9:27am turbo pump on

2020-01-13

• 12:40pm in chamber
  • S2000085 in CR1
  • S2000086 in CR2
  • S2000087 in CR3
  • S2000088 in CR4
• 12:41pm roughing pump on
• 12:51pm turbo pump on

2020-01-14

• 10:10 am in chamber
  • S2000089 in CR1
  • S2000090 in CR2
  • S2000091 in CR3
  • S2000092 in CR4
• 10:16 am roughing pump on
• 10:26 am turbo pump on

2020-01-17

• 9:16 am in chamber
  • S2000093 in CR1
  • S2000094 in CR2
• 9:17 am roughing pump on
• 9:26 am turbo pump on

2017-08-18

• I ran a sweep of the central position in the two ESD setup with both set at the same voltage. There were two designs that maximized excitation by different metrics, the design with a 3 mm shift from the original design maximized excitation overall, but the 20 kHz mode was worse by a bout a factor of 5. The design with a -2 mm shift maximized the high frequency modes, particularly the modes most affected by the shift.
• MATLAB crashed shortly after the sweep so I will have to recreate the RMS plots of the dynamic modes later.

LIGO-T1600466

• S1600432 shows some residual on face, close to the edge, probably from first contact
• S1600433 looks ok
• S1600434 shows a small residual on the face, the edge, probably from first contact, and a back spot, probably a residual of the contamination
• S1600435 shows a large halo on the face, like what you get when solvents dry on the surface leaving some traces
• S1600436 has some red residual on the edge, likely first contact
• S1600437 the surface looks ok but the edge has a clear reddish color

Sample with edges flame polished in Glasgow

Installation

• into the chamber and balanced at 11am. Pump down started at 11:00am.
• it looks like the turbo pump shaked the sample too much and moved it significantly. At 11:44am I had to tweak a bit the input steering periscope to avoid the outgoing beam to be clipped on the pickoff mirror
• roughing pump off at 2:27pm
• excitation at 2:36pm (2000 V, 30 s)

Results

% Freq        First Q of pair   Second Q of pair
1117.4        2.3392e+07        2.3392e+07
2555.9        1.8650e+07        1.8650e+07
4441.1        1.3003e+07        1.3003e+07
6759.2        1.6003e+07        1.5656e+07
6781.8        1.4795e+07        1.4795e+07
9499.2        5.6765e+06        5.6765e+06
10219.5       1.3148e+07        2.7060e+06
10222.3       1.3909e+07        4.2609e+04
11444.0       2.0756e+06        6.5364e+05
12649.4       1.0264e+07        8.7228e+06
12650.7       8.6808e+06        8.6808e+06
14176.3       1.0290e+07        1.0290e+07
14177.5       1.0185e+07        1.0185e+07
16113.7       1.0856e+07        9.7535e+06
16202.5       8.6733e+06        5.0176e+06
18619.0       1.3113e+07        1.3113e+07
18622.1       1.4864e+07        1.4864e+07
20149.0       1.4047e+06        1.4047e+06
21348.8       6.9944e+06        6.9944e+06
21353.3       8.0679e+06        3.1734e+05
23529.5       1.3076e+07        1.3076e+07
24482.3       9.6841e+06        9.6841e+06
24669.1       4.8629e+06        4.8629e+06
24670.5       6.3609e+06        6.3609e+06
25499.2       5.2216e+06        5.2216e+06
25828.0       3.3780e+06        3.3780e+06
27101.0       1.4934e+07        1.4934e+07
27103.5       1.4956e+07        1.4956e+07
28883.5       1.2076e+07        1.2076e+07
29068.6       1.1494e+07        1.1494e+07
29072.0       9.7555e+06        9.7555e+06
29190.0       5.9610e+06        5.9610e+06
29193.2       7.9280e+06        7.9280e+06
29502.2       7.8254e+06        7.8254e+06
30867.0       6.3681e+06        6.3681e+06
31267.0       1.6836e+06        1.4541e+05
32194.4       5.3275e+06        5.3275e+06
32200.0       5.9215e+06        2.6587e+06

The following plot compares the Q measured on this sample yesterday here at Caltech with the GeNS system, with the measurement perfomed by Raymond Robie in Glasgow.

- blue dots: measurements on the flame polished sample here at Caltech
- orange crosses and yellow triangles: Raymond’s measurements on the flame polished sample at in Glasgow (after annealing)
- purple crosses: typical Q values measured on disk samples (not annealed nor flame polished) here at Caltech

Flame polishing of the edges did not change significantly the Q we measure with the GeNS system. However, the GeNS system rovide systematically higher Q values for basically all measurable modes.

Cleaning and baking (200 C air foe SS and 120 for Al) parts for the new vacuum chamber

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 too close to the disk, so I moved it a bit up.

Pump down started at about 2:38pm LT.

I realigned all optical levers to measure the 50mm disks. In brief, I moved the input 2" mirrors, the in-vacuum 2" mirrors and the PZT mirrors so that the beam hits the 50mm sample and gets back into the QPD. Re-aligned everything to the horizontal reference using water.

I repeated the analysis for bulk and shear losses described in an early elog entry, with the same coating, but after annealing at 500C for 9 hours. 

The COMSOL model is the same as before, so the dilution factors are the same, except that this time I could measure a few more modes at high frequency:

As in the previous analysis, I fitted four different models:
1) one single loss angle for both bulk and shear, constant in frequency
2) one single loss angle for both bulk and shear, linear in frequency
3) separate bulk and shear loss angles, constant
4) separate bulk and shear loss angles, linear in frequency 

The data strongly favor the last model: two loss angles for shear and bulk, linearly dependent on frequency (Bayes factor -22.7 for the second best model, which is the frequency dependent single loss angle).

The results are below. 

Single constant loss angle

Single loss angle, linearly dependent on frequency

Bulk and shear loss angles, constant

Bulk and shear loss angles, linearly dependent on frequency