Abstract

Details

1. Only AA0 was connected to KEPCO 30A power supply
2. All three AAs were connected to KEPCO 30A power supply
3. Only AA0 was connected to the dedicated power supply
4. All three AAs were connected to the dedicated power supply

1. Only AA0 was connected to the KEPCO power supply
2. AA0 and AA1 were connected to the KEPCO power supply
3. AA0 and AA2 were connected to the KEPCO power supply
4. AA2 were connected to the KEPCO power supply

DGS Regular maintenance day (5/20) 

Stepper motor
 [Check the motor.]
  Check if power supply can be controlled by BIO
  Check if the script can be started
  Checked that the limit switches installed are green.
 [Check result]
  No problem
  
Release Sensor
 [Checked the Release Sensor.]
 Checked that Release Sensor is 0, 1: Seated.
 [Check result]
 ETMX, ETMY, ITMX, ITMY : No problem

Picomotor
 [Confirmation]
  PingTest is performed.
 [Result]
  Only known

 NG: 
  PR2(IM),SR3(BF)
   => It was hung and recovered.
  
  MCI,STM1,
  AS_WFS,POP_POM,POS_POM,POM1
  MCF(MCO,MCI)
  　=> Checked only, no recovery work was done.

 OK:
  ETMX,ETMY,ITMX,ITMY
  BS(IM,BF),SRM(IM,BF),SR2(IM,BF),SR3(IM,STM)
  PRM(IM,BF),PR2(BF),PR3(IM,BF)
  MCE,IMMT1,IMMT2,OMMT1,OMMT2,OSTM
  REFL_WFS, (new check item)POP,POP2,POS,POS2
  PCAL(EX1,EX2,EY1,EY2):Not checked because it is ON only when used.

Temperature controller
 [Checked]
 Is the temperature acquisition working properly?

 [Check result] ・Is the temperature acquisition working properly?
  No problem

Precision air conditioning
 [Check Contents]
 Is the temperature acquisition working properly?

 [Result]
  No problem

FunctionGenerator
 (Confirmation) ・Is there a ping response?
 Is there a ping response?
 Are all EPICS channels alive?
  [sitemap]-[Commissioning]-[ALS FG]-[Xarm],[Yarm].
 [Check result]
 X and Y PLLs are working properly.

DATE : 2022/05/20 10:58 UTC
ARM : X
TEMP ITM : 250.4
TEMP ETM : 218.0
VALUE : 1482.6
ERROR : 7.0

Measured data is stored to /users/Commissioning/data/Finesse/Xarm/20220520-105819/

[Ikeda, Yasui-san]

1. The network of WS in BS and IMC was connected from the 100Mbps SW in the computer room.
Therefore, we installed a 1Gbps LAN from the SW behind the PSL room and reconnected it.

 Before modification
  Computer Room N1 Rack SW -> BS sw -> IMC(IOO area) sw
 After modification :
  SW behind PSL room -> IMC(IOO area) sw -> BS sw 

 BS SW was changed to AC adapter instead of PoE power supply.
 It is connected to Port 18 of the SW behind the PSL room. (Fig-1)

2. Removal of network SW above the central rack
 This SW was also beaded from the 100Mbps SW in the computer room.
 This bead connection is very inefficient.
  BS SW -> SR2+SR2 2nd SW -> SRM SW -> SR3 & OMC SW
 Removed SWs are SR2 SW, SRM SW, SR3 SW and OMC SW. 

 Next equipment will be relocated to PICO net, so LAN cable is still there but SW was removed.
  PICO 
   OMMT1/OSTM
   AS WFS
   POS_POM

 The SW above the BS has not been removed.
 A POP/GREEN POM PICO was connected to this with power on.
 This will remain until these are relocated to the Pico network.

 A new LAN was connected from the SW in the machine room to the LAN in the Instrument Control Rack.
 It was connected to Port 18 of the SW on the Y side of the machine room. (Fig-2,3)

 The removed SW is placed on the shelf next to the BS WS. 
 

[Ikeda, Yasui-san]

Summary
This is a continuation of the DAQ Timig Error investigation.

In the investigation of K-Log#20464, I tested the possibility that the overall efficiency might be higher if HyperThread is Disable.

However, I am not sure of the effect at present.
This may be a bit out of date, but T1500227 5.3.2 states that Hyperthreading - Enabled (DAQ code is multi-threaded).

Correspondence

We changed the HyperThread setting of k1dc0 to Enable in the BIOS.(Fig.1)

Next, We tried the method that caused the DAQ error in K-Log#20563 last time.

> 2. Connected all RTPCs (C1, C2, C3) directly to the SW of NETGEAR to which k1dc0 is connected.

Connected directly to the same SW as k1dc0 but the error frequency was low and improved.

Before these changes, the frequency of occurrence was several times/day.
We will leave it as is for the rest of the week.

[ Yano, Satou, Akutsu ]

The BS Mid-size baffle frame and plates were unpacked and placed in the clean booth. These were placed on the tabletop on the +Y side of the BS-PR2. Be careful not to touch the solblack treatment on the surface as it is easily scratched.

After getting rid, to a good extent, of the bumps in measured IP transfer functions, I calculated inter-calibration factors between geophones and LVDTs in L, T and Y.

In klog entry 20778, the ratio ( IPL-lvdt / IPL-geo ) is shown in dB, which is not a suitable scale. For this analysis the appropriate scale is linear.  What I did is the following:

1. I measured the usual IP transfer function in L, T and Y, using the LVDTs and the geophones.
2. Using the cost function written in klog 20410 for SRM, I calculated the inter-calibration factor a, which should multiply the geophone transfer function. 

The results are the following and are also shown in the plots:

• Longitudinal: 1.02922
• Transverse: 1.03941
• Yaw: 0.97688

These values still have to be written in the filter banks.

I implemented calibration factors for IMMT1 OpLevs.
Also, I changed the gains of TM OpLev DC controls.

This entry reports the results of the recalibration of the geophones.

Recalibration was necessary because a bump appeared in the transfer functions around 1 Hz. See the original report in klog 20534.

It's better to describe what I did in a document and upload it to JGWDoc, for this klog entry I just give a cursory description:

1. I measured the TFs from yaw actuation to two different sets of outputs:
   • Set 1: raw output of the individual geophones, in units of cnt/cnt.
   • Set 2: displacement output of the individual geophones, using their calibration transfer functions that produce the bumps, in units of um/cnt.
2. I fitted each of these TFs in Set 2 with a mathematical model that does not allow the bump to appear, and fits well the resonance frequency and DC amplitude. For the fit, the values were weighed with a factor 1/f in order to favor lower frequencies where the resonance is.
3. Then I defined a function containing the geophone parameters to determine (Ge , f0 and eta):  integrator(s) * m2um * ( 1 / H_geo ) * hp(s) * ( 1 / preamp ) * cnt2V * tf_raw
   • Integrator: conversion from velocity to displacement,
   • m2um: conversion from metres to micrometres.
   • H_geo( Ge, f0 , eta ) = Ge * s**2 / (omega0**2 + 2 * omega0 * eta * s + s**2 )
   • s = 1j *2 * pi * f
   • omega0 = 2 * pi * f0
   • hp: high-pass filter with four poles located at 3 mHz.
   • preamp = 940, this factor compensates the preamplifier gain.
   • cnt2V = 2 * 20 / 2**16, ADC conversion factor in units of V/cnt.
   • tf_raw: raw transfer function from Set 1.
4. Then I fitted the function defined in step 3 to data generated with the function calculated in step 2.
5. With Foton, I put all these filters in the filter banks and measured again TFs.

In the table, the original values measured by Fujii-kun (entry 7059) and the new ones are shown.

265.114

1.079

0.2990

260.6117

1.125

0.2881

248.8686

1.204

0.2386

The observations are:

• All the resonance frequencies f0 decreased, namely, by 15, 68 and 197 mHz for H1, H2 and H3 respectively.
• The damping factors Eta decreased by factors of 0.49, 0.51, 0.54 for H1, H2 and H3 respectively.

The plots show the following quantities:

• With new filters: TF measured with corrected geophone parameters (step 5 above).
• Aimed with measured velocity: TF calculated with the measured raw TF (Set 1 in step 1) and the geophone calibration function with new parameters.
• Theoretical aim: Transfer function calculated in step 2.
• Original with bump: the name is explanatory.

From the plots, it's clear that the results are alright and, therefore, I'll continue with the following step, which is inter-calibration between geophones and LVDTs. However, it seems the results could still be improved.

I implemented the TCam automatic fit code for ETMY.  Fig1 is the example of fitting. The last one is ITMY.

By the way, the archive web page is super convenient. Thanks!

I took photos of ETMX by Tcam on 2022/05/19 9:03 ~ 9:11 JST and ITMX on 9:03, 9:11 JST.

Details

• GreenX was in the flashing state without IR lock.
• For Tcam configuration, (gain, exposure time) =(470, 10)
• I took two kinds of photos by turning on the illuminator and turning off the illuminator for ETMX
  • illuminator OFF (see Fig1)
    • 9:04, 9:10, 9:11
  • illuminator ON (see Fig2)
    • 9:05, 9:07, 9:08
• I compared these photos and fitting results. Although the appearance were slightly different by the illuminator, that doesn't affet the fitting results.
• From fitting TCam photo, the location of ETMX center was estimated as (x, y) = (1919.4, 1344.1) pixel.

I measured the transfer functions of the GAS filters in PRs and compared each other. There is not much difference between the three suspensions except the DC magnitude in SF. 

OpLevs of ETMY are centered after offloading work of ETMY (klog20787).
We didn't touch TM tilt OpLevs because it is almost at the center.

OpLevs of ITMY are centered after offloading work of ITMY (klog20787).
We didn't touch TM OpLevs because they are almost at the center.

[Tamaki, Ushiba]

Abstract:
We installed whitening filters for MN photosensors of EY suspension.
Even though MNH1 sensor noise setill seems limited by ADC noise, the whitening filter works very well.

Detail:
We installed a universal whitening filter (S1808687) at EY0 rack (U33) for the measure of ADC noise problem (klog20682).
BIO settings can be seen in fig1 (switch #2 and #4 are ON. Since this board is used for MN/IM photosensor signal, only ch1 and ch2 are used).

After installing and setting whitening filters, we set dewhitening filters in the MN_OSEMINF filter banks at FM3 (dw_temp).
The dewhitening filter is just a gain of about 0.18 but all dewhitening filter gain was decided by measuring the signal ratio before and after installing the whitening filters.

After that, we measured the noise spectra of photosensors (fig2).
Red and blue shows the photosensor noise and ADC noise at corresponding channels, respectively.
As you can see, all noise except for MNH1 is higher than ADC noise, while they are limited by ADC noise before installing whitening filters (klog20684).
Since current MNH1 noise spectra is lower than the ADC noise measured on 10 of May, ADC noise level seems not stable.
Anyway, S/N can be improved by installation of whitening filters; so it is worth installing them for all Type-A suspensions.

Hirata, Yano, Satou N., Akutsu

Summary

Completed installing the mid-size baffles in the PRM chamber. Note importantly that the nominal point at which the main IR beam passes through is about 6-mm displaced from the center of the aperture of the AR mid baffle so that the surrounding two ghost beams can be peacefully arrested.

Installation procedure

We mostly followed the installation procedure document (JGW-T2214066), so please have a loot at it. The preparation was reported in 20783.

• Fig. 1 shows the mid-side baffles before installed. The one in front is for the HR side, while the other is for the AR side. The AR side baffle has a smaller aparture than the HR side one (there was a discussion at the design review at that time...); the AR side baffle needs to catch two main ghost beams, surrounding the main beam, so it has such a smaller aperture.
• Called SAFE state to the PRM and PR2, turned the KOACH filters at the relevant places, and set the PR HR target and PR2 HR target.
• Set a laser level (in green) in front of PR2 HR to throw a vertical reference line by illuminating the PR2 HR and PRM HR. Also set a laser level (in green) in front of the PRM HR to throw a horizontal reference line onto the PRM HR.
• Set the mid-size baffles at HR and AR side of PRM by referring these vertical and horizontal refrence lines. As anticipated, some shims were inserted under the baffles to match the height. Every time the suspended optical bench for the baffles was once lowered to sit on the bottom structure, and set teh baffle, did some fine adjustement with respect to the reference, and release the table to check the situation, and again let it sit down on the bottom, and fixed the clamps, and then, release the table again.
• The HR one was not so difficult to set.
• The AR one needed some iterations with using two positioners. Anyway finally we put it with respect to the reference line. Maybe partly due to the suspended table is pitching (see 17635).
• Fig. 2 just shows a scene of still mid-way of the installation, but you can feel how these mid-size baffles have been residing in the PRM chamber.

Confirmation

• We called ALIGNED state to PRM to see where the two ghost beams will come on the AR mid-size baffles. Fig. 3 shows an IR viewer's view for the AR side baffle surface. You can see two ghost beam spots. The nominal positions of these ghost beams can be found in the installation procedure document (JGW-T2214066).
• Need to revisit the IR beam optical axis. With respect to the vertical reference line from the laser level (located at close to PR2) illuminating PR2 and PRM, the IR beam axis seemed horizontally displaced (3-4 mm at PR2 target in the plus Y direction (Fig. 4), while 2-3 mm at the in-between the PRM-IMM chambers in the minus Y direction (Fig. 5)) with respect to this reference when IO guardian is at PROVIDING_STABLE_LIGHT. I also tried to compare them by additonially calling XARM guardian to ALIGN_IMMTs, but checking the IR beam will mean cutting the IR beam so it was difficult to say something definite today. Need to re-consider the tactics. Anyway, maybe this relative horizontal displacement would be due to IMMT1's arbitrary alignment. So, later we need to revisit this issue for more precise adjustment of the optical axis just before closing the central chambers.

Disk8 of Pod# on E18 that had error was replaced to a new 4TB disk.

The new disk was added as a global spare disk which is a spare for both Array #1 and Array #2.

I installed the high power coil driver (S1706229), which has been used in IYV and repaired, to the OMC rack for the OMMT1.

I measured the transfer functions of the BF damper in PRs and compared each other. There is not much difference between the three suspensions. There is coupling from the Y-mode in the V transfer function in PR3.

The Scratch line of PRM recoilmass was aligned with same position which we used this time. GAS nominal is here. (Please see attached picture.)