Restarted Corner pumpdown this morning ~8:08 am

Starting Pressure at PT180: 390 Torr

Stopping Pressure at PT180: 32.7 Torr

Today's pumping time: 9 hours and 25 minutes

Mobile ISP1000 pumps are isolated and powered off for the weekend. Turbopump station and backing scroll pump are powered on and isolated from the main volume.

Wed afternoon Nergis and I went to SQZT7 to get a couple of beam profiles after the ZM4 preload was adjusted, before the ZM5 swap. 

We took two measurements with the same psams settings but different centering on ZM2, based on what Camilla and Madi did in 90946 .  The data labeled as  nominal position is for these sliders where Camila reports that the beam on ZM2 is 5.85" off the table, and the data labeled raised is for these sliders where the beam is actaully lowered to 5.75".  The center of ZM2 should be 5.5" off the table.  M^2 went from 1.35 to 1.28 horizontal and 1.25 vertical with the improved centering, and the relative astigmatism also improved from 0.13 to 0.02 Ryan found the definition of relative astigmatism on page 122 (pdf page 129) of the BC207 manual here.

ZM4 strain guage was saturated when the PZT was much above 100V, so this morning Daniel came to SQZ racks with Ryan and I and changed some resistors, Daniel will add the details.  ZM4 strain guage is now working well, with values between -4.1V to 2.7V, and Ryan turned the servo back on. 

Yesterday morning, I noticed that for some psams settings, the beam was clipping on the top periscope mirror and that then we measured quite high M^2 values.  I wondered if clipping on that persicope could explain more of our M^2 measurements.  Today Ryan Short and I carefully aligned the psams to get the beam centered on the two irises on SQZT7.  We raised the top periscope mirrors, and Ryan adjusted both periscope mirrors to get the beam well centered on the irises again.  When we did this, we noticed that only one of the bolts that holds the top periscope mount to the periscope structure was tight.  

After this Ryan and I did another round of profile measurements with the new preload and working strain guage on ZM4.  We took 5 points over the range of ZM4 with ZM5 PZT at 100V, with the ZM5 strain guage not working, then took 3 points with ZM5 at a strain guage of -4.5V which is 20V on the PZT, because the ZM5 strain guage is working there we can compare these to measurements taken before ZM5 stopped working.  

Unfortunately, even after moving the periscope mirror the M^2 values are in the range of 1.4 to 1.23, so the clipping on the periscope mirror wasn't the explanation for the high M^2

Jennie W

While trying to debug some other SPI readout problems I noticed that the main SPI overview screen had one of the readback channel names wrong.

The 'DISP OUT' block in red at the right of the screen should readout the channel 'H1:SPI-H23_DIFFDISP_DIAG_INMON' and 'H1:SPI-H23_DIFFDISP_DIAG_OUT16' in its bottom row.

These were reading out the channel above 'REFNULL' in boith cases. I corrected this in SPI_CUST_OVERVIEW.adl file and committed to the svn. In the picture the readouts are circled on the right with the channels they readout shown on the left in the filter banks.

TITLE: 07/10 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

IFO is in IDLE for MAINTENANCE

Pumpdown continues - see attached screenshot

Ryan S, Sheila and Daniel also did some work at SQZT7

In other news,

• HEPI pumps blip - alog 90984
• GC Maintenance - WP 13395

LOG:

Ibrahim

Got a message at 14:58 UTC to "Check HEPI pump station pressures".

At 14:58,

• the pressure in HEPI Corner Station PS4_PRESS1 (brown) dipped by -5PSI and then spiked by +0.3PSI before recovering. Stable now.
• the pressure in all other HEPI Corner Stations dropped by -0.3PSI from nominal and then spiked to +0.1PSI before recovering. It's stable now. Plots are below.

I checked the End Stations too but nothing was seen (also attached).

TITLE: 07/10 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 7mph Gusts, 3mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.08 μm/s 
QUICK SUMMARY:

IFO is in IDLE for MAINTENANCE

No specific tasks today since it's RDO Friday for most

Corner pumpdown yesterday afternoon (alog 90979)

(Jordan, Travis, Richard, Filiberto, Randy, Gerardo)

Corner pumpdown started Thursday afternoon, around 4:40 pm local time.
We setup the twin mobile ISP-1000 scroll pump stations at the YBM turbo station, we chose this area due to the real estate available, the other 2 stations are a bit crowded.  After setting up all of the required equipment the pumpdown was started with procedure E2300169, to setup the turbo pump unit for the pumpdown, then Jordan and Filiberto covered procedure M1300464 to make sure all high voltage DC power supplies were off, then continued following E2300443 to start the pumpdown with the ISP-1000 scroll pumps through the YBM turbo pump.  Pumpdown was done for about 2 hours taking us down to 340 Torr.  The pumpdown was stopped at 7:02 pm local time for the night.

No issues to report during the startup of the pumpdown, however something to note is that during the blow down of the vacuum envelope the system was not pressurized, last minute work on the different chambers did not allowed to pressurize the envelope. 

As per WP 13401.  In preparation for upcoming daqd upgrades I'm working to move the run number server off of h1daqscript0 and onto the HA container cluster.  I have the new instance running with the current run number database.  I just need to configure the framewriters to point to it.  I will do that next week.   The run number server helps keep the run number that is put into the frames consistent between the two frame writers.

This is a step to retiring the h1daqscript0 machine once we remove the daqd's px dolphin.

TITLE: 07/09 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: Preparations continued today for corner volume pumpdown.
LOG:

A couple days ago I noticed that HAM3 HEPI H4 L4C had almost 0 signal compared to the other L4Cs on that chamber. I didn't have time until this afternoon to look at it. L4C proof masses can get stuck (or something) so I tried waking it up by tapping on the L4C casing or (gently) slapping the locked crossbeam. Neither seemed to work, so I powered off the interface chassis on the pier, and swapped the cables between the H4 and V4 L4C. This seemed to work. The H4 L4C still worked when I swapped the cables back. Probably need to watch this down the road, maybe think about adding a famis task to monitor, because this is the second "stuck" L4C I've found on the IMC HAMs.

Matt, Sophie, Camilla

CHETA uses a Linear translation stage with a 100mm range. +50mm is moving L2 upstream (towards M3), -50mm is moving downstream (towards M4).

Currently if a position out of this range is requested, the translation stage becomes frozen. The only way we've found to reset it is to unplug from the chassis and plug into the Newport Driver (ESP300), turn MTR ON and then press home for Axis 1. We are working with the Beckhoff team to hard code limits so this will not happen in the future. 

Per FRS 38164, the unused viewport located at A1F1 and A2F1 on HAM7 have been removed and blanked off.  These viewports are being moved to HAM3, so serial number, etc. will be recorded in a separate aLog.

Late entry for VAC - Gerardo, Travis, Jordan, Tyler and Randy put the doors on HAM3 yesterday afternoon.  They did -Y first, then +Y.  Getting the doors craned over and transferred to the Forklift could only happen at the corner near the TCSy table, so was a tight fit at that transfer point.

These were the last doors to go on for this vent window.

Well done team.

Ken, Preeti, TJ

We've made transfer functions to see and compare the level of cross coupling between P and Y at both sites for the top stage of BBSS. The L1 traces were rescaled to match the H1 magnitude for the PtoP comparison at 0.1Hz. The scaling factor was 3.72. This was done to compensate for the DAC differences between the sites. All of the L1 traces were multiplied by this scale factor. All plots are found in the attached PDF. 

This morning, with Mitch and Shoshana, I went into the nozzle between HAM3 and BSC2, via the HAM3 door to fix the broken H3 actuator. I had to remove a couple baffles to get in and get access to the hatch over the H3 actuator, once the hatch was off, I found the pin on the back of the actuator terminal block had come lose, probably when I was in there to do the CPS upgrade. I probably should have checked this wire after I finished that swap, but it there was no way to see that anything was wrong, I had to grab the wire and pull on it. Once that was reconnected and I put everything back together, we did a quick chamberside test and H3 was driving again. I've now completed close out tfs, attached image, and run a CPS linearity measurement to check the new cpses. The linearity test plots failed in a way that didn't save the data, but I do have the terminal output of the test which agrees with HAM7: 

  'Actuator H1 to  CPS H1'

Linear regression y= 1.862 x + 245 

    'Actuator  V1 to  CPS V1'

Linear regression y= 1.890 x + -771 

    'Actuator  H2 to  CPS H2'

Linear regression y= 1.845 x + -271 

    'Actuator  V2 to  CPS V2'

Linear regression y= 5.105 x + 2771 

    'Actuator  H3 to  CPS H3'

Linear regression y= 5.073 x + 1543 

    'Actuator  V3 to  CPS V3'

Linear regression y= 5.119 x + 2882 

At some point after doors go on, I will want to try to fix the cps linearity test script and run it again, among the many other measurements I will need for HAM3.

Filing a late report, last week I measured the resistance of the strain gauge on the PSAMS for ZM5 suspension in HAM7 chamber. This is to investigate the inconsistent behavior (voltage drop/open loop issues) of the strain gauge attached to the PSAMS on ZM5 - details posted in LHO alog 90783.

To measure the resistance of the strain gauge and confirm if anything is broken, I decided to check it chamber side (on the racks in the LVEA). To locate the chassis in the LVEA I referred to the A+ SUS HAM 7 (sush7) System Wiring Diagrams (D2000202_V12), page 04 (ZM5, M2 PSAMS). This document pointed me towards SQZ-R1, Slot U2, where the chassis D2000555 was located. At first, I switched off the chassis and then unplugged cable no 6 which was connected to the JIG Box (J8-Metal PCB Jumper Box DB25 Male female). Then I  connected a breakout board to cable no 6. For measuring the resistance of the strain gauge, I looked into D2000383 to find the correct pins (Camille Makarem (CIT) also talked to the vendor and sent me the pin number, as given in E2500225). This is as follows,

700 Ohms between Ex+ and Ex-

350 Ohms between signal+ and Ex-.

From the pinouts in https://dcc.ligo.org/LIGO-E2500225, this should be

700 Ohms between pins 1 and pins 3/2

350 Ohms between pins 6 and pins 2/3
 

Chamber side this comes to be pin 12 & 25 and pin 11 & 25. Using a multimeter, I got the following readings,

Pin 12 & 25 = 706 Ohms (looks good)

Pin 11 & 24 = 360.5 Ohms (looks good)

The chassis was powered on after the measurements were complete and cable 06 reconnected to the JIG box and secured using two screws (which were missing). The above measured numbers are as per the strain gauge manufacturer. However, It could be possible that the soldering is coming off and giving us open loop sometimes, if not all times. We will continue to investigate this issue and if we are not able to fix it then the plan is to replace it with a spare unit. A spare ZM5 PSAMs unit is currently being prepared by Camille Makarem and should be shipped to LHO within a day or two. We will then start working on swapping out the faulty unit with spare one, in-situ.  

(Jordan, Owen, Jake, Gerardo)

The cryotrap cooldown continues, we continue to pump on the cryotrap volume with a turbo pump, the turbo is backed with a SS500 aux cart.

Small changes were the removal of the calibrated leak from the RGA tree, along with the removal of other components in preparation to install an incoming small ion pump next week.

Current pressure in the cryotrap volume is 7.38X10^-10 Torr.

Due to a mistake in past CHETA models there is more astigmatism then expected on the tables and a change in beam size at the ITM. The astigmatism can be fixed by rotating L1 around the vertical axis and the beam size can be changed by movind L2 using the translation stage in each setup. Using a modified Fintrace model the required rotation angle and translation for each table  as they are currently populated at LHO (0922, 0918) and LLO (0919, 0851) have been calculated and are shown below. 
The tables below give the current astigmatism and then the angles and translations such that the x and y beamsize on the ITM is 52.7mm with no astigmatism. 

This code is avaliable in the CHETA modelling repository.

Without translating of L2 astigmatism can be removed but the beam size is still unoptimised.