ID 
Date 
Author 
Type 
Category 
Subject 
381

Wed Jul 26 21:22:50 2017 
Zach  Electronics  Modeling  Parametric Sweep Results 
20170726
 I resolved the major bugs in the parametric sweep scripts and ran low resolution sweeps of the gap between the ESD and sample (Gap Sweep) and the spacing between the ESD arms (ESD Arm Gap Sweep).
 The arm gap sweep largely behaved in a reasonable way with a maximum excitation at a 1.25 mm gap. However modes 14, 19, and 25 did not follow the general trends and had sharp drops and increases compared to the other modes.
 The sample gap sweep had less intuitive behavior, all of the modes followed the same general double peak trend that drops to zero when the gap is 1.5 mm. I cannot explain exactly why it is behaving that way, I will run a higher resolution sweep and examine the geometry in greater detail.

380

Wed Jul 26 16:22:22 2017 
Gabriele  General  Measurements  S1600528 S1600531 
20170726
 4:14pm in chamber
 S1600528 in CR1
 S1600531 in CR2
 4:16pm roughing pump on
 4:23pm turbo pump on
 Excitations

Quiet time before excitation: 1185160841
Excitation broadband: 1185160876
Quiet time after excitation: 1185160901

Quiet time before excitation: 1185168131
Excitation broadband: 1185168167
Quiet time after excitation: 1185168192

Quiet time before excitation: 1185175422
Excitation broadband: 1185175457
Quiet time after excitation: 1185175482

Quiet time before excitation: 1185182712
Excitation broadband: 1185182747
Quiet time after excitation: 1185182772

Quiet time before excitation: 1185190002
Excitation broadband: 1185190038
Quiet time after excitation: 1185190063

Quiet time before excitation: 1185197293
Excitation broadband: 1185197329
Quiet time after excitation: 1185197354
20170727
 4:30pm, valve closed, pumps stopped, vented

379

Wed Jul 26 09:27:40 2017 
Zach  Electronics  Modeling  Sweeping the space between ESD and sample 
20170726
 I ran a sweep of the gap between the ESD and the sample, first from .5 mm to 1 mm. That sweep suggested that there is a significant jump in force across almost all of the modes at 1 mm. To confirm this I double checked the geometry and it appears that COMSOL is building everything as expected when changing the spacing parameter. Then I ran a finer sweep in .02 mm increments for the spacing between .9 and 1.1 mm. Once again it appears there is a large jump as the gap approaches 1 mm, but the behavior does not seem to be symmetric about that point, the force appears to diminish linearly as the gap increases beyond 1 mm. I will run a sweep of the ESD arm spacing along with the vertical gap to confirm that the jump occurs when the gap between the ESD and the sample is equivalent to the spacings between the ESD arms.

Attachment 1: Gap_near_one.jpg


378

Tue Jul 25 13:38:30 2017 
Zach  Electronics  Modeling  Parametric Sweep of ESD gap 
20170725
 I completed a short sweep of the gap between the drive and the sample, between .5 and 1 mm in .1 mm increments. It appears that a 1 mm distance is the ideal distance by approximately a factor of two. I will next sweep larger distances and see how the force profile behaves at greater distances.

377

Tue Jul 25 11:22:37 2017 
Gabriele  General  Measurements  S1600548 S1600550 S1600538 
20170725
 11:12am in chamber (non standard order is not a typo!!)
 S1600548 in CR1
 S1600550 in CR2
 S1600538 in CR3
 11:13am roughing pump on
 11:22am turbo pump on
 Excitations:

Quiet time before excitation: 1185056320
Excitation broadband: 1185056355
Quiet time after excitation: 1185056380

Quiet time before excitation: 1185057610
Excitation broadband: 1185057645
Quiet time after excitation: 1185057670

Quiet time before excitation: 1185058900
Excitation broadband: 1185058935
Quiet time after excitation: 1185058960

Quiet time before excitation: 1185060190
Excitation broadband: 1185060226
Quiet time after excitation: 1185060251

Quiet time before excitation: 1185061481
Excitation broadband: 1185061516
Quiet time after excitation: 1185061541

Quiet time before excitation: 1185062771
Excitation broadband: 1185062806
Quiet time after excitation: 1185062831

Quiet time before excitation: 1185064061
Excitation broadband: 1185064096
Quiet time after excitation: 1185064121

Quiet time before excitation: 1185065351
Excitation broadband: 1185065386
Quiet time after excitation: 1185065411
20170726
 4:05pm valve closed, pumps stopped, venting

376

Mon Jul 24 16:06:11 2017 
Gabriele  General  Measurements  S1600530 S1600532 S1600537 S1600539 
20170724
 3:55pm installed in chamber
 S1600530 in CR1
 S1600532 in CR2
 S1600537 in CR3
 S1600539 in CR4
 3:58pm roughing pump on
 4:06pm turbo pump on
 Excitations:

Quiet time before excitation: 1184986754
Excitation broadband: 1184986789
Quiet time after excitation: 1184986814

Quiet time before excitation: 1184988044
Excitation broadband: 1184988079
Quiet time after excitation: 1184988104

Quiet time before excitation: 1184989334
Excitation broadband: 1184989369
Quiet time after excitation: 1184989394

Quiet time before excitation: 1184990625
Excitation broadband: 1184990660
Quiet time after excitation: 1184990685

Quiet time before excitation: 1184991915
Excitation broadband: 1184991950
Quiet time after excitation: 1184991975

Quiet time before excitation: 1184993205
Excitation broadband: 1184993240
Quiet time after excitation: 1184993265

Quiet time before excitation: 1184994495
Excitation broadband: 1184994530
Quiet time after excitation: 1184994555

Quiet time before excitation: 1184995785
Excitation broadband: 1184995820
Quiet time after excitation: 1184995845
20170725
 11:00am valve closed, pumps stopped, venting

375

Mon Jul 24 09:13:45 2017 
Zach  Electronics  Modeling  Parametric Sweep 
20170724
 I wrote a MATLAB script that is capable of sweeping parameters, the code is attached. The next step is to create nested loops so that I can sweep multiple parameters in a single run. I also should add a function in the script to eliminate the modes that cannot be measured by the experimental setup.
 My first sweep was for the gap between electrodes and swept from 1 to 2 mm. In the plot the gap grows from steps 1 to 6 and the only obvious effect in the plot is a decrease in force from the highest mode. Intuitively it makes sense that a wider gap would decrease the force because the electric field is diminished by spreading out the electrodes.
 I would like to add a parameter for the overlap of the electrodes, but this would require substantial redesigning of the COMSOL model due to the multilevel dependency on parameters.

Attachment 2: forcesweep.m

fpro = zeros(6, 27);
no = 1;
for count = 1:.2:2
gap = strcat(num2str(count), ' [mm]')
model = fst2(gap);
forces;
fpro(no, :)= product(:);
no = no + 1;
end

374

Sat Jul 22 13:05:46 2017 
Gabriele  General  Measurements  S1600533 S1600535 S1600536 S1600547 
20170722
 12:55pm in chamber
 S1600533 in CR1
 S1600535 in CR2
 S1600536 in CR3
 S1600547 in CR4
 Added neutral densities
 12:57pm roughing pump on
 1:05pm turbo pump on
 Excitations

Quiet time before excitation: 1184803575
Excitation broadband: 1184803611
Quiet time after excitation: 1184803636

Quiet time before excitation: 1184804866
Excitation broadband: 1184804901
Quiet time after excitation: 1184804926

Quiet time before excitation: 1184806156
Excitation broadband: 1184806191
Quiet time after excitation: 1184806216

Quiet time before excitation: 1184807446
Excitation broadband: 1184807481
Quiet time after excitation: 1184807506

Quiet time before excitation: 1184808736
Excitation broadband: 1184808771
Quiet time after excitation: 1184808796

Quiet time before excitation: 1184810027
Excitation broadband: 1184810062
Quiet time after excitation: 1184810087

Quiet time before excitation: 1184811317
Excitation broadband: 1184811352
Quiet time after excitation: 1184811377

Quiet time before excitation: 1184812607
Excitation broadband: 1184812642
Quiet time after excitation: 1184812667

More excitations

Quiet time before excitation: 1184878758
Excitation broadband: 1184878794
Quiet time after excitation: 1184878819

Quiet time before excitation: 1184880049
Excitation broadband: 1184880084
Quiet time after excitation: 1184880109

Quiet time before excitation: 1184881339
Excitation broadband: 1184881374
Quiet time after excitation: 1184881399

Quiet time before excitation: 1184882629
Excitation broadband: 1184882664
Quiet time after excitation: 1184882689

Quiet time before excitation: 1184883919
Excitation broadband: 1184883954
Quiet time after excitation: 1184883979

Quiet time before excitation: 1184885210
Excitation broadband: 1184885245
Quiet time after excitation: 1184885270

Quiet time before excitation: 1184886500
Excitation broadband: 1184886536
Quiet time after excitation: 1184886561

Quiet time before excitation: 1184887791
Excitation broadband: 1184887826
Quiet time after excitation: 1184887851
20170724
 3:28pm valve closed, venting

373

Fri Jul 21 14:55:02 2017 
Gabriele  General  Measurements  Shear and bulk losses in annealed tantala 
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

Attachment 7: postannealing_linear_bulk_shear.png


372

Fri Jul 21 08:42:09 2017 
Gabriele  General  Measurements  S1600525 
20170721
 8:30am, in chamber (CR4)
 8:32am, roughing pump on
 8:41am, turbo pump on
 Excitations

Quiet time before excitation: 1184697303
Excitation broadband: 1184697338
Quiet time after excitation: 1184697363

Quiet time before excitation: 1184698593
Excitation broadband: 1184698628
Quiet time after excitation: 1184698653

Quiet time before excitation: 1184699883
Excitation broadband: 1184699918
Quiet time after excitation: 1184699943

Quiet time before excitation: 1184701173
Excitation broadband: 1184701208
Quiet time after excitation: 1184701233

Quiet time before excitation: 1184702463
Excitation broadband: 1184702499
Quiet time after excitation: 1184702524

Quiet time before excitation: 1184703754
Excitation broadband: 1184703789
Quiet time after excitation: 1184703814

Quiet time before excitation: 1184705044
Excitation broadband: 1184705079
Quiet time after excitation: 1184705104

Quiet time before excitation: 1184706334
Excitation broadband: 1184706369
Quiet time after excitation: 1184706394
20170722
 12:13pm, valve closed, pumps off

371

Thu Jul 20 11:37:01 2017 
Zach  Electronics  Modeling  Matlab Script 
20170720
 I believe my MATLAB script successfully calculates the force distribution into each of the modes specified by the parameters. My previous error was caused by my neglecting the proportionality factor of . Now the force order of magnitude is on the order of 10^{3}. I am currently unclear how to think about the units of the mode shapes from the disk_frequencies script, but I will pick it apart more carefully and try to figure that out. Then it will be a matter of converting units so that it matches with the N/m^3 from the COMSOL script and then comparing with real lab results. It seems to me that the error in force distribution should be inversely proportional to the number of modes calculated, in which case it would be useful to determine an appropriate number of modes to calculate.

Attachment 1: forces.m

par.a = 75e3/2; % radius [m]
par.h = 1.004e3; % thickness [m]
par.E = 73.2e9; % Young's modulus [Pa]
par.nu = 0.155; % Poisson's ratio
par.rho = 2202; % density [kg/m^3]
%Calculate fundamental modes of the disk
[freqs, modes, shapes, x, y] = disk_frequencies(par, 10000, 1, 'shapes', 0.5e3);
%Now we extract the force profile from the COMSOL model
... 27 more lines ...

370

Wed Jul 19 21:19:14 2017 
Gabriele  General  Measurements  Shear and bulk losses in tantala 
To quantify which of the fit below is the most significant, I did a Bayesian analysis (thanks Rory for the help!).
In brief, I compute the Bayes factors for each of the models considered below. As always in any Bayesian analysis, I had to assume some prior distribution for the fit parameters. I used uniform distributions, between 0 and 20e4 for the loss angles, and between 100e6 and 100e6 for the slope. I checked that the intervals I choose for the priors have only a small influence on the results.
The model that has the highest probability is the one that considers different bulk and shear frequency depent loss angles. The others have the following relative probabilities
One loss angle constant: 1/13e+13
One loss angle linear in frequency: 1/5.5
Bulk/shear angles constant: 1/48784
Bulk/shear angles linear in frequency: 1/1
So the constant loss angle models are excluded with large significance. The single frequency dependent loss angle is less probable that the bulk/shear frequency dependent model, but only by a factor of 5.5. According to the literature, this is considered a substantial evidence in favor of frequency dependent bulk/shear loss angles.
Quote: 
Results
One loss angle  constant
One loss angle  linear in frequency
Bulk and shear  constant
Bulk and shear  linear in frequency


369

Tue Jul 18 09:13:08 2017 
Gabriele  General  Measurements  Shear and bulk losses in tantala 
S1600525 has been coated in Fort Collins with 480nm of pure tantala. I used the emasured loss angles (after deposition, before annealing) to estimate the shear and bulk loss angles.
Model
First, my COMSOL simulation shows that even if I don’t include the drumlike modes, I still have a significant scatter of shear/bulk energy ratio. The top panel shows indeed the ratio shear/bulk for all the modes I can measure, and the variation is quite large. So, contrary to my expectation, there is some room for fitting here. The bottom panel just shows the usual dilution factors.
Then I tried to fit the total losses in my sample (the substrate is negligible) using 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 angels, linear in frequency
Instead of using Gregg harry's technique (taking pairs of losses together), I simply fit the whole datasets with the assumptions above. I derived the 95% confidence intervals for all parameters. I also weighed each data point with the experimental uncertainty. I’m not sure yet how to compare the performance of the various models and decide which is the best one, since clearly the more parameters I plug into the model, the better the fit gets.
If I use two different loss angles, but constant, I get numbers similar to what Gregg presented at the last Amaldi conference ( G1701225), but inverted in bulk and shear. I cross checked that I didn’t do any mistake. Instead, if I allow linear dependency on frequency of bulk and shear, I get a trend similar to the one in Gregg's slides.
My plan is to have this sample annealed today or tomorrow and measure it again before the end of the week.
Results
One loss angle  constant
One loss angle  linear in frequency
Bulk and shear  constant
Bulk and shear  linear in frequency

368

Fri Jul 14 16:43:24 2017 
Zach  Electronics  Modeling  Force profile matlab script 
20170714
 I have completed a rough, but functioning script that calculates the modal force profiles. The force values are still coming out incorrect (on the order of 10^14) but the script can take in my model as a .m file and return an array with a force value per mode. I am attaching both the .m file and the matlab script
 I have done very little work with the numerical integration itself, based on the 2D numerical integration code I received I just appended a z component and left it at that so when I return from Livingston I will fix that component

Attachment 1: forces.m

par.a = 75e3/2; % radius [m]
par.h = 1.004e3; % thickness [m]
par.E = 73.2e9; % Young's modulus [Pa]
par.nu = 0.155; % Poisson's ratio
par.rho = 2202; % density [kg/m^3]
%Calculate fundamental modes of the disk
[freqs, modes, shapes, x, y] = disk_frequencies(par, 10000, 1, 'shapes', 0.5e3);
%Now we extract the force profile from the COMSOL model
... 41 more lines ...

Attachment 2: faster.m

function out = model
%
% faster.m
%
% Model exported on Jul 14 2017, 14:47 by COMSOL 5.2.1.262.
import com.comsol.model.*
import com.comsol.model.util.*
model = ModelUtil.create('Model');
... 403 more lines ...

367

Wed Jul 12 15:08:59 2017 
Zach  Electronics  Modeling  Model of actuator and sample 
20170712
 I am attaching the first fully functioning model of the actuator and sample. I cleared both meshes and solutions to make the file a reasonable size, but they can quickly be built/solved again.

Attachment 1: Force_Model.mph

366

Thu Jul 6 12:48:54 2017 
Zach  Electronics  Modeling  Resolving the factor of two 
20170706
I resolved the factor of two from Griffiths' discussion of dipoles in nonuniform electric fields. The force on a dipole in a nonuniform field is where is the difference in the field between the plus end and the minus end. Component wise, where d is a unit vector. This holds for y and z, the whole thing can also be written as . Since p=qd, we can write .
Jackson derives it differently by deriving the electrostatic energy of a dielectric from the energy of a collection of charges in free space. He then derives the change in energy of a dielectric placed in a fixed source electric field to derive that the energy density w is given by . This explicity explains the factor of two and is an interesting alternative explanation. 
365

Thu Jul 6 12:08:35 2017 
Zach  Electronics  Modeling  Checking physical parameters 
20170706
 I compared the electric field and the polarization to make sure that those calculations made sense. Since due to the linear dielectric, I plotted the electric field and the polarization divided by the proportionality constant and they match exactly.
 This confirms both the constant value and the polarization distribution but gets me no closer to resolving the factor of two

364

Wed Jul 5 16:40:51 2017 
Zach  Electronics  Modeling  Force disparityimprovement 
20170705
 In order to improve my data I shrunk the region of the finer meshing slightly and made the mesh even smaller and then recalculated the force profiles. This time I tried sampling regions inside the disc rather than immediately at the surface. The attached graphs were sampled at the center of the disc. These two techniques vastly improved the data, now the profiles appear the same, but the magnitudes differ by a factor of 2 again. Previously this was due to an error in my calculation of the force, now I do not believe this to be the case. I will leave my work here for the purposes of my first report, it is an interesting result. I also restricted my data set to the finely meshed box which resolved the earlier data display issue.

363

Wed Jul 5 12:01:51 2017 
Zach  Electronics  Modeling  Force plotsCorrect plots, force issue 
20170705
 I sorted out my mathematical lapse in logic and computed the correct force profiles in the perpendicular direction in both disks. The issue is that now the force profiles don't match up. The fact that there is a measured force distribution for the E^2 case outside the disk is only an artifact of the numerics because it is being calculated only from the electric field data which is defined outside the sample. It can be easily removed for final plots once the force distributions are matched by either redefining the cut plane or putting a data filter specifically on the E^2 plot. The jumps in the E^2 plot suggest that the meshing is still too large, I will try to fix this first, hopefully it will help resolve the difference.

362

Wed Jul 5 10:01:29 2017 
Gabriele  General  Measurements  S1600547 S1600548 S1600549 S1600550 
20170705
 NOTE: at 9:40am switched off turbo pump in CR0 to avoid vibrations
 NOTE: boxes are labeled as S1600546/547/548/549 but must be relabeled as S1600547/548/549/550
 9:53am, in chamber
 S1600547 in CR1
 S1600548 in CR2
 S1600549 in CR3
 S1600550 in CR4
 9:54am roughing pump on
 10:02am turbo pump on
 Excitations:

Quiet time before excitation: 1183323620
Excitation broadband: 1183323655
Quiet time after excitation: 1183323680

Quiet time before excitation: 1183330910
Excitation broadband: 1183330945
Quiet time after excitation: 1183330970

Quiet time before excitation: 1183338200
Excitation broadband: 1183338235
Quiet time after excitation: 1183338260

Quiet time before excitation: 1183345490
Excitation broadband: 1183345525
Quiet time after excitation: 1183345550

Quiet time before excitation: 1183352780
Excitation broadband: 1183352815
Quiet time after excitation: 1183352840

Quiet time before excitation: 1183360070
Excitation broadband: 1183360105
Quiet time after excitation: 1183360130

Quiet time before excitation: 1183367360
Excitation broadband: 1183367395
Quiet time after excitation: 1183367420

Quiet time before excitation: 1183374650
Excitation broadband: 1183374685
Quiet time after excitation: 1183374710
20170706
 3:45pm, valve closed, vented, pumps stopped

361

Fri Jun 30 16:27:56 2017 
Zach  Electronics  Modeling  Double Checking Model 
20170630
 In order to confirm the accuracy of my model I checked some easily computable quantities between what real values and what COMSOL produced. My expected electric field magnitude between the electrodes is 10^{6} V/m and COMSOL reads out 1.015*10^{6 }which is less than a 2% error. When I went to compute the electric field gradient however, I discovered that I had been calculating my derivatives wrong, I was calculating full derivatives when I needed partial derivatives. Due to some subtleties of the numerics involving curl calculations are the order of the variables, in order to calculate a partial I belive that I have to map the results of the electric field to Lagrange elements.

360

Fri Jun 30 11:02:18 2017 
Zach  Electronics  Modeling  Matching Forces 
20170630
 I adjusted the plot parameters slightly so that it only showed the actual force profile on the sample in the direction perpendicular to the sample surface. Additionally I compared the two methods of computing the force, as and as . The profile of the force in both instances appear equal, but they differ in magnitude by exactly a factor of 2, I plotted the force computed with the explicit polarization doubled and the force magnitudes matched exactly. I'm still not entirely sure where this factor of two could be coming from.

359

Thu Jun 29 16:40:41 2017 
Zach  Electronics  Modeling  Accurate model and force profile 
20170629
 I created a much more accurate model of the current ESD setup from the technical drawings. My resulting ESD has dimensions of 21.3x24.3x.1mm with 1 mm spacings and 17.5 mm long electrode arms. The sample has a diameter of 75 mm and thickness of 1mm, the ESD is 1mm below the sample in the current model. I still have to compare the technical drawings to confirm that is the actual distance in the current lab setup.
 I was able to calculate the force profile on the disk from the ESD. COMSOL struggled to resolve the data with a small mesh size over the whole domain, so I created a region of extremely fine mesh around the ESD and the disk and then made the rest of the mesh size normal sized. Over the domain near the ESD my mesh size ranges from 2.5*10^{3} to .25 mm and over the rest of the domain it's automatically setup at the normal size.
 The force on a single dipole is given as , since fused silica is isotropic it's polarization is proportional to E so . The electric suscepitibility of fused silica is 1.09, I plotted the profile of the force perpendicular to the plane of the disk and exported data files of the full vector quantity of the force for use with Matlab.

358

Thu Jun 29 13:15:01 2017 
Alastair, Gabriele  General  General  Laser polishing 
We laser polished S1600546, 547, 548, 549, 550 and 551 
357

Wed Jun 28 15:50:15 2017 
Gabriele  General  Measurements  S1600541 
20170628
We plan to leave S1600541 in vacuum for a long period, and measure the Q's periodically.
 3:48pm, S1600541 installed in CR0
 3:50pm, roughing pump on
 4:35pm turbo pump on

356

Tue Jun 27 14:17:47 2017 
Zach  Electronics  Modeling  Further plots and improving models 
20170627
 I built a new model of the ESD to determine whether or not the spikes in the electric field at the corners was affecting the results enough that it had to be accounted for in further models. To create the model, I created a 2D profile of the arm used in my original model and filleted the corners at a radius of .05 mm, since the electrode model is .1 mm thick, this made completely rounded edges. In creating this model I caught an earlier mistake in the original one, I only set one half of the surface of the electrodes to have a potential or to ground, the "bottom" was left with no charge. I fixed this mistake and then compared the two models at a potential of 1000 V. For speed of computation I ran both models with a finer mesh size and then calculated the electric field at approximately the middle of the ESD, 1mm above the fourth electrode arm. For the rounded electrodes the field had a value of 84024 V/m and for the rectangular electrodes the field had a value of 80728 V/m, which is less than a 4% difference in field magnitude. Furthermore, the field shapes appear nearly indistinguishable; I am confident from this test that I can proceed modelling the arms of the ESD as rectangles.

Attachment 1: E_field_corner.png


Attachment 2: E_field_round.png


355

Tue Jun 27 09:20:16 2017 
Alena  General  Annealing  Annealing run (546551) on 3" wafers  Crime 06/27/2017 
Started annealing run https://dcc.ligo.org/T1700293
Will be ready by June 28th afternoon 
354

Sat Jun 24 12:59:27 2017 
Gabriele  General  Measurements  S1600541 S1600542 post annealing 
20170624
 12:47pm in chamber
 S1600541 in CR1
 S1600542 in CR3
 12:50pm roughing pump on
 12:59pm turbo pump on
 Excitations

Quiet time before excitation: 1182524202
Excitation broadband: 1182524237
Quiet time after excitation: 1182524262

Quiet time before excitation: 1182535092
Excitation broadband: 1182535127
Quiet time after excitation: 1182535152

Quiet time before excitation: 1182545982
Excitation broadband: 1182546017
Quiet time after excitation: 1182546042

Quiet time before excitation: 1182556872
Excitation broadband: 1182556907
Quiet time after excitation: 1182556932

Quiet time before excitation: 1182567762
Excitation broadband: 1182567797
Quiet time after excitation: 1182567822

Quiet time before excitation: 1182578652
Excitation broadband: 1182578687
Quiet time after excitation: 1182578712

Quiet time before excitation: 1182589542
Excitation broadband: 1182589577
Quiet time after excitation: 1182589602

Quiet time before excitation: 1182600432
Excitation broadband: 1182600467
Quiet time after excitation: 1182600492
20170628
 3:36pm, valve closed, vented, pumps stopped

353

Fri Jun 23 12:02:12 2017 
Zach  Electronics  Modeling  Plots 
20170623
 I created plots of the E field and potential from my rough model of the ESD. This model has 1mm electrode arm widths and spacings, the length of each arm is 16 mm, and the resulting total size is 38mm x 20 mm x 0.1 mm. One comb has ten arms while the other has nine to match the actual ESD currently in use in the lab.
 I set the ten arm comb to a potential of 100 V and the other to ground. I then used physics controlled mesh with an extremely fine element size to computer the simulations. With mesh sizes larger than extra fine, there was clearly nonphysical error in the electric field and potential graphs that appeared as inexplicable field lines, spikes, and coarseness in the plots.
 To create readable plots of the potential I created a Cut Plane in the center of the ESD perpendicular to both the arms and the plane of the device. The plots are attached with a milimeter length scale. I created a filled contour plot of the potential that is very clean, I tried a couple of different options for the electric field because it is harder to represent well. I created a contour plot for the norm of the electric field as well as superimposing a streamline plot of the field lines over that. Everything behaves generally as expected though I do suspect the spikes in electric field at the edges of each electrode are due to the fact that they are sharp corners and not smooth edges.

Attachment 1: Potential.png


Attachment 2: E_w_Lines.png


Attachment 3: Mesh.png


352

Thu Jun 22 15:37:20 2017 
Zach  Electronics  Modeling  Beginning modeling 
20170622
 Created the geometry of the ESD by creating blocks and joining them with Unions. I then created a block to serve as the domain and added air to that region
 This plot is a combination of a Surface plot of the potential and a Streamline plot of the electric field
 I created another model of the ESD with more accurate measurements to the real thing and added the silica disc to the model

351

Thu Jun 22 13:16:37 2017 
Zach  Electronics  Modeling  Beginning with COMSOL 
20170621
 4:30 pm Installed COMSOL, began modeling current ESD by creating parameters and the first arm of the comb

350

Wed Jun 21 17:04:20 2017 
Alena  General  Annealing  Annealing run (541542) on 3" wafers  Crime 06/25/2017 
Started an annealing run https://dcc.ligo.org/LIGOT1700271
Will be ready by Friday morning

349

Tue Jun 20 16:01:27 2017 
Gabriele, Zach, Alastair  General  Measurements  S1600541 S1600542 (laser polished) 
20170620
 The two substrates were laser polished (CO2 power ~ 23 W)
 3:50pm installed in chamber
 S1600541 in CR1
 S1600542 in CR3
 3:52pm roughing pump on
 4:00pm turbo pump on
 Excitations

Quiet time before excitation: 1182045787
Excitation broadband: 1182045822
Quiet time after excitation: 1182045887

Quiet time before excitation: 1182056717
Excitation broadband: 1182056752
Quiet time after excitation: 1182056817

Quiet time before excitation: 1182067648
Excitation broadband: 1182067683
Quiet time after excitation: 1182067748

Quiet time before excitation: 1182078578
Excitation broadband: 1182078613
Quiet time after excitation: 1182078678

Quiet time before excitation: 1182089509
Excitation broadband: 1182089544
Quiet time after excitation: 1182089609
20170621
 1:56pm, valve closed, pumps off

348

Fri Jun 16 15:56:55 2017 
Gabriele  General  Measurements  S1600541 S1600542 
20170616
20170619
20170620

347

Thu Jun 15 11:20:13 2017 
Gabriele  General  Measurements  S1600539 S1600540 
20170615
 11:13am in chamber
 S1600539 in CR1
 S1600540 in CR3
 11:14am roughing pump on
 11:23am turbo pump on
 Excitations

Quiet time before excitation: 1181596817
Excitation broadband: 1181596852
Quiet time after excitation: 1181596917

Quiet time before excitation: 1181607747
Excitation broadband: 1181607782
Quiet time after excitation: 1181607847

Quiet time before excitation: 1181618677
Excitation broadband: 1181618712
Quiet time after excitation: 1181618777
20170616

346

Wed Jun 14 16:53:54 2017 
Gabriele  General  Measurements  S1600546 
20170614
 4:44pm in chamber
 4:47pm roughing pump on
 4:55pm turbo pump on
 Excitations

Quiet time before excitation: 1181533731
Excitation broadband: 1181533766
Quiet time after excitation: 1181533831

Quiet time before excitation: 1181544661
Excitation broadband: 1181544696
Quiet time after excitation: 1181544761

Quiet time before excitation: 1181555591
Excitation broadband: 1181555626
Quiet time after excitation: 1181555691
20170615

345

Fri Jun 2 16:04:12 2017 
Gabriele  General  Measurements  S1600525 S1600526 
20170602
 3:55pm in chamber:
 S1600525 in CR1
 S1600526 in CR3
 3:56pm roughing pump on
 4:04pm turbo pump on
 Excitations:

Quiet time before excitation: 1180561453
Excitation broadband: 1180561488
Quiet time after excitation: 1180561553

Quiet time before excitation: 1180572383
Excitation broadband: 1180572418
Quiet time after excitation: 1180572483

Quiet time before excitation: 1180583313
Excitation broadband: 1180583348
Quiet time after excitation: 1180583413

Quiet time before excitation: 1180594243
Excitation broadband: 1180594278
Quiet time after excitation: 1180594343

Quiet time before excitation: 1180605173
Excitation broadband: 1180605208
Quiet time after excitation: 1180605273

Quiet time before excitation: 1180616103
Excitation broadband: 1180616138
Quiet time after excitation: 1180616203

Quiet time before excitation: 1180627033
Excitation broadband: 1180627068
Quiet time after excitation: 1180627133

Quiet time before excitation: 1180637963
Excitation broadband: 1180637998
Quiet time after excitation: 1180638063
20170606
 8:10am, pumps stopped, valve closed, chamber vented
20170608
 3:50pm, in chamber
 S1600525 in CR1
 S1600526 in CR3
 3:50pm roughing pump on
 4:00pm turbo pump on
 Excitations:

Quiet time before excitation: 1181012200
Excitation broadband: 1181012235
Quiet time after excitation: 1181012300

Quiet time before excitation: 1181023130
Excitation broadband: 1181023165
Quiet time after excitation: 1181023230

Quiet time before excitation: 1181034060
Excitation broadband: 1181034095
Quiet time after excitation: 1181034160

Quiet time before excitation: 1181044990
Excitation broadband: 1181045025
Quiet time after excitation: 1181045090

More excitations

Quiet time before excitation: 1181488352
Excitation broadband: 1181488388
Quiet time after excitation: 1181488453

Quiet time before excitation: 1181499283
Excitation broadband: 1181499318
Quiet time after excitation: 1181499384

Quiet time before excitation: 1181510214
Excitation broadband: 1181510249
Quiet time after excitation: 1181510314
20170614
 4:40pm, pumps stopped, valve closed, vented

344

Tue May 16 13:44:01 2017 
Gabriele  General  General  Effect of meshing on dilution factor simulation 
I ran a series of COMSOL simulations to compute the dilution factors of a coated disk with the dimensions we are currently using (75mm diameter, 1mm thick, 1um of coating).
The mesh is generated as follows:
 a free triangular mesh with defined maximum element size is generated on the coating top surface
 the triangular mesh is swept across the coating, generating a defined number of layers
 the same mesh is swept through the substrate, generating a defined number of layers
The plots below shows the effect on the dilution factor convergence of the three parameters above. It turns out that the size of the surface trinagular mesh is the most relevant parameter, followed by hte number of layers in the coating. Instead, the number of layers in the substrate is not particularly relevant.

343

Mon May 15 13:19:12 2017 
Gabriele  General  Measurements  Q measured again after four weeks in vacuum 
I measured again two of the substrates that have been sitting in the pumpeddown vacuum chamber for about four weeks. The pressure now is below 1e7 Torr. There is no significant difference between the two sets of measured Q values.

342

Thu Apr 20 09:10:25 2017 
Gabriele  General  Measurements  S1600542 S1600543 S1600544 S1600545 
20170420
 9:09am in chamber
 S1600542 in CR1
 S1600543 in CR2
 S1600544 in CR3
 S1600545 in CR4
 10:50am, roughing pump on
 11:00am turbo pump on
 Excitations:

Quiet time before excitation: 1176767876
Excitation broadband: 1176767911
Quiet time after excitation: 1176767976

Quiet time before excitation: 1176773406
Excitation broadband: 1176773441
Quiet time after excitation: 1176773506

Quiet time before excitation: 1176778936
Excitation broadband: 1176778971
Quiet time after excitation: 1176779036

Quiet time before excitation: 1176784466
Excitation broadband: 1176784501
Quiet time after excitation: 1176784566

Quiet time before excitation: 1176789996
Excitation broadband: 1176790031
Quiet time after excitation: 1176790096

Quiet time before excitation: 1176795526
Excitation broadband: 1176795561
Quiet time after excitation: 1176795626

Quiet time before excitation: 1176801056
Excitation broadband: 1176801091
Quiet time after excitation: 1176801156

Quiet time before excitation: 1176806586
Excitation broadband: 1176806621
Quiet time after excitation: 1176806686
20170513
 Excitations:

Quiet time before excitation: 1178680521
Excitation broadband: 1178680556
Quiet time after excitation: 1178680621

Quiet time before excitation: 1178691451
Excitation broadband: 1178691486
Quiet time after excitation: 1178691551

Quiet time before excitation: 1178702381
Excitation broadband: 1178702416
Quiet time after excitation: 1178702481

Quiet time before excitation: 1178713311
Excitation broadband: 1178713346
Quiet time after excitation: 1178713411

Quiet time before excitation: 1178724241
Excitation broadband: 1178724276
Quiet time after excitation: 1178724341

Quiet time before excitation: 1178735171
Excitation broadband: 1178735206
Quiet time after excitation: 1178735271

Quiet time before excitation: 1178746101
Excitation broadband: 1178746136
Quiet time after excitation: 1178746201

Quiet time before excitation: 1178757031
Excitation broadband: 1178757066
Quiet time after excitation: 1178757131

341

Fri Apr 14 13:49:17 2017 
Gabriele  General  Measurements  S1600538 S1600539 S1600540 S1600541 
20170414
 1:45pm in chamber
 S1600538 in CR1
 S1600539 in CR2
 S1600540 in CR3
 S1600541 in CR4
 1:48pm roughing pump on
 2:00pm turbo pump on
 Excitations

Quiet time before excitation: 1176267253
Excitation broadband: 1176267289
Quiet time after excitation: 1176267354

Quiet time before excitation: 1176281784
Excitation broadband: 1176281819
Quiet time after excitation: 1176281884

Quiet time before excitation: 1176296314
Excitation broadband: 1176296349
Quiet time after excitation: 1176296414

Quiet time before excitation: 1176310844
Excitation broadband: 1176310879
Quiet time after excitation: 1176310944

Quiet time before excitation: 1176325374
Excitation broadband: 1176325409
Quiet time after excitation: 1176325474

Quiet time before excitation: 1176339904
Excitation broadband: 1176339939
Quiet time after excitation: 1176340004

Quiet time before excitation: 1176354434
Excitation broadband: 1176354469
Quiet time after excitation: 1176354534

Quiet time before excitation: 1176368964
Excitation broadband: 1176368999
Quiet time after excitation: 1176369064
20170420
 8:58am valve closed, venting, pumps stopped

340

Tue Apr 11 14:07:48 2017 
Gabriele  General  Measurements  S1600533 S1600535 S1600536 S1600537 
20170411
 2:02pm, in chamber
 S1600533 in CR1
 S1600535 in CR2
 S1600536 is CR3
 S1600537 in CR4
 2:05pm roughing pump on
 2:15pm, turbo pump on
 Excitations:

Quiet time before excitation: 1175994832
Excitation broadband: 1175994867
Quiet time after excitation: 1175994932

Quiet time before excitation: 1176000362
Excitation broadband: 1176000397
Quiet time after excitation: 1176000462

Quiet time before excitation: 1176005892
Excitation broadband: 1176005928
Quiet time after excitation: 1176005992

Quiet time before excitation: 1176011422
Excitation broadband: 1176011457
Quiet time after excitation: 1176011522

Quiet time before excitation: 1176016953
Excitation broadband: 1176016988
Quiet time after excitation: 1176017053

Quiet time before excitation: 1176022483
Excitation broadband: 1176022518
Quiet time after excitation: 1176022583

Quiet time before excitation: 1176028013
Excitation broadband: 1176028048
Quiet time after excitation: 1176028113

Quiet time before excitation: 1176033543
Excitation broadband: 1176033578
Quiet time after excitation: 1176033643
20170414
 12:58pm, valve closed, pumps off

339

Mon Apr 10 16:22:12 2017 
Gabriele  General  Measurements  S1600529 S1600530 S1600531 S1600532 
20170410
 4:10pm, in chamber:
 S1600529 in CR1
 S1600530 in CR2
 S1600531 in CR3
 S1600532 in CR4
 4:14pm, roughing pump on
 4:24pm, turbo pump on
 Excitations:

Quiet time before excitation: 1175916121
Excitation broadband: 1175916156
Quiet time after excitation: 1175916221

Quiet time before excitation: 1175921651
Excitation broadband: 1175921686
Quiet time after excitation: 1175921751

Quiet time before excitation: 1175927181
Excitation broadband: 1175927216
Quiet time after excitation: 1175927281

Quiet time before excitation: 1175932711
Excitation broadband: 1175932746
Quiet time after excitation: 1175932811

Quiet time before excitation: 1175938241
Excitation broadband: 1175938276
Quiet time after excitation: 1175938341

Quiet time before excitation: 1175943771
Excitation broadband: 1175943806
Quiet time after excitation: 1175943871

Quiet time before excitation: 1175949301
Excitation broadband: 1175949336
Quiet time after excitation: 1175949401

Quiet time before excitation: 1175954831
Excitation broadband: 1175954866
Quiet time after excitation: 1175954931
20170411
 11:09 valve closed, pumps stopped

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.
Realigned everything.
I installed a sample in the chamber to reflect a beam back inot the QPD. Checking the QPD signals over a hour and more did not show any sign of excess noise or instability. 
337

Fri Apr 7 14:12:52 2017 
Eric, Gabriele  General  General  S1600525 S1600526 S1600527 S1600528 
20170407
 2:12pm in chamber, pumps on
 S1600525 in CR1
 S1600526 in CR2
 S1600527 in CR3
 S1500528 in CR4
 Excitations

Quiet time before excitation: 1175653360
Excitation broadband: 1175653395
Quiet time after excitation: 1175653460

Quiet time before excitation: 1175660690
Excitation broadband: 1175660725
Quiet time after excitation: 1175660790

Quiet time before excitation: 1175668021
Excitation broadband: 1175668056
Quiet time after excitation: 1175668121

Quiet time before excitation: 1175675351
Excitation broadband: 1175675386
Quiet time after excitation: 1175675451

Quiet time before excitation: 1175682681
Excitation broadband: 1175682717
Quiet time after excitation: 1175682782

Quiet time before excitation: 1175690012
Excitation broadband: 1175690047
Quiet time after excitation: 1175690112

Quiet time before excitation: 1175697342
Excitation broadband: 1175697377
Quiet time after excitation: 1175697442

Quiet time before excitation: 1175704672
Excitation broadband: 1175704707
Quiet time after excitation: 1175704772
20170410
 11:19am, valve closed, pumps off

336

Thu Mar 30 15:23:44 2017 
Gabriele  Optics  General  Swapped HeNe laser in CR0 
The JDSU HeNe laser 1103P that I was using is dead. I swapped it with a JDSU 1125P borrowed from the 40m. 
335

Thu Mar 30 13:33:13 2017 
Gabriele  General  Measurements  S1600477 
20170330
 1:23pm, in chamber CR2
 1:25pm, roughing pump started, clamps on
 1:34pm turbo pump on
 Excitations:

Quiet time before excitation: 1174958541
Excitation broadband: 1174958576
Quiet time after excitation: 1174958641

Quiet time before excitation: 1174960471
Excitation broadband: 1174960506
Quiet time after excitation: 1174960571

Quiet time before excitation: 1174962401
Excitation broadband: 1174962436
Quiet time after excitation: 1174962501

Quiet time before excitation: 1174964331
Excitation broadband: 1174964366
Quiet time after excitation: 1174964431

Quiet time before excitation: 1174966261
Excitation broadband: 1174966296
Quiet time after excitation: 1174966361

Quiet time before excitation: 1174968191
Excitation broadband: 1174968226
Quiet time after excitation: 1174968291

Quiet time before excitation: 1174970122
Excitation broadband: 1174970157
Quiet time after excitation: 1174970222

Quiet time before excitation: 1174972053
Excitation broadband: 1174972088
Quiet time after excitation: 1174972153

334

Wed Mar 29 11:57:09 2017 
Gabriele  General  Measurements  MIT sample 
20170329
 11:47am, in chamber CR0, balanced
 11:48am roughing pump on
 12:00pm, turbo pump on
 Excitations:

Quiet time before excitation: 1174976553
Excitation broadband: 1174976585
Quiet time after excitation: 1174976607

Quiet time before excitation: 1174977837
Excitation broadband: 1174977869
Quiet time after excitation: 1174977891

Quiet time before excitation: 1174979121
Excitation broadband: 1174979153
Quiet time after excitation: 1174979175

Quiet time before excitation: 1174980405
Excitation broadband: 1174980437
Quiet time after excitation: 1174980459

Quiet time before excitation: 1174981689
Excitation broadband: 1174981721
Quiet time after excitation: 1174981743

Quiet time before excitation: 1174982973
Excitation broadband: 1174983006
Quiet time after excitation: 1174983028

Quiet time before excitation: 1174984258
Excitation broadband: 1174984291
Quiet time after excitation: 1174984313

Quiet time before excitation: 1174985543
Excitation broadband: 1174985575
Quiet time after excitation: 1174985597

333

Wed Mar 22 12:47:40 2017 
Gabriele  General  Measurements  S1600469 S1600471 S1600481 S1600483 
20170322
 12:38am, in chamber
 S1600469 in CR1
 S1600471 in CR2
 S1600481 in CR3
 S1600483 in CR4
 12:40 roughing pump on
 12:47 turbo pump on
 Excitations

Quiet time before excitation: 1174263313
Excitation broadband: 1174263348
Quiet time after excitation: 1174263413

Quiet time before excitation: 1174265243
Excitation broadband: 1174265278
Quiet time after excitation: 1174265343

Quiet time before excitation: 1174267173
Excitation broadband: 1174267208
Quiet time after excitation: 1174267273

Quiet time before excitation: 1174269103
Excitation broadband: 1174269138
Quiet time after excitation: 1174269203

Quiet time before excitation: 1174271033
Excitation broadband: 1174271068
Quiet time after excitation: 1174271133

Quiet time before excitation: 1174272963
Excitation broadband: 1174272998
Quiet time after excitation: 1174273063

Quiet time before excitation: 1174274893
Excitation broadband: 1174274928
Quiet time after excitation: 1174274993

Quiet time before excitation: 1174276823
Excitation broadband: 1174276859
Quiet time after excitation: 1174276924
20170329
 11:40am removed from chamber

332

Sat Mar 11 17:33:45 2017 
Gabriele  General  Measurements  S1600490 
20170310
 4:38pm, in chamber
 4:40pm, roughing pump on
 4:59pm, turbo pump on
20170322
