CP4 update

Kyle, Gerardo, Chandra

We moved PT-245 cold cathode gauge cable to the full-range hot cathode gauge on turbo inlet temporarily for the bake exercise (which caused some alarms today). Thus, the pressure readout (at PT-245 on MEDM) is not accurate - will calibrate in software on Monday; need to read out the voltage displayed on MY screen and convert to mbar per the attached plot. Current reading is 2.38 V which converts to 8e-8 mbar or 6e-8 Torr. Since screen shots read remotely don't capture voltage, we put the voltage display up in the control room, found here: https://lhocds.ligo-wa.caltech.edu/cr_screens/png/video0-1.png

We started to test CP4 regen. First flowed GN2 through the reservoir at 20-50 SCF/H (after LN2 was vaporized in tower outside). Regen controls system needed some work - discovered a few thermocouple wires were backwards, at both the Watlow heater and Beckhoff rack and one of the exhaust TCs does not work due to some broken wires in well - TE252B (note cable in Watlow controller is labeled 253, not 252). We need to figure out how to satisfy the two gate valve "closed" interlocks. We tried to jumper the limit switch signal at Beckhoff, and also the pin switch for LOTO. We'll work with Richard and Patrick on Monday to see what signals the software is looking at. Once we override this interlock we will test the regen heater and Watlow over-limit switch.

Attached are a couple RGA scans from today and from Tuesday. Note that today's scan was taken after cold GN2 was passed through CP4 so there may have been some water pumping. Both are faraday mode.

 

Halting attended pump down of Vertex Volume

Will resume Monday morning.  

Note that "in-chamber work" in HAM6 is still prohibited until further notice.

70W Amp Install Update

J. Oberling, E. Merilh, P. King

Today we installed the new 35W Front End power monitor pick-off.  We removed the unused AOM port from the back wall of the FE (1st attachment), wired the pick-off, and installed it in front of the output of the MOPA (2nd attachment).  The half-wave plate in front of the FE FI was adjusted to minimize the NPRO power delived to the MOPA and the NPRO current was decreased from 2.222A to 1.0A.  This was to minimize the output of the FE while adjusting and aligning the new pick-off.  Using a WinCAM, we positioned the pick-off such that it was not clipping the beam, and aligned it using the 3 set screws (can be seen on the 2nd attachment) to maximize the signal seen by Beckhoff; this was a very tedious and time-consuming process.  Once the PD output was aligned we slowly increased the NPRO current back to its nominal operating value of 2.222A.  All being good, we then adjusted the half-wave plate to deliver the maximum NPRO power to the MOPA.  Once again, there were no issues with the beam profile and the output power of the MOPA read 36.2 W.  We calibrated the new pick-off to this value.

On Monday, we will recover the alignment to the PMC if necessary (the new pick-off could potentially change this alignment), then proceed with installation of the new PBSC and half-wave plate.  These 2 components replace the mirror that is currently being used to direct the beam into the HPO, and allow us to change the beam path either toward the 70W amplifier or toward the HPO; the latter will allow operation of the just the 35W FE laser, if necessary.

Common mode sero medms

Fixed the display logic for Out 2 on the CM board medms.

Ops Shift Summary

TITLE: 02/23 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
LOG:

15:52 UTC Terry to LVEA to work on squeezer table
16:24 UTC Nutsinee to ISCT6
16:53 UTC Ed to end X, Filiberto to ISCT6 (Beckhoff safety)
17:01 UTC Filiberto done
17:06 UTC Gerardo to LVEA to unpause pumping of vertex
17:06 UTC Ed starting work at end X
17:11 UTC Peter to chiller/diode room for documentation
17:13 UTC Ed to end Y
17:28 UTC Ed starting work at end Y
17:32 UTC Ed done, heading back
17:39 UTC Peter done
17:41 UTC Marc to mid Y to drop off and receive parts
18:07 UTC Marc back
18:08 UTC Georgia to end Y, taking electric field measurements with grounded battery pack
18:20 UTC Jason to PSL enclosure
18:25 UTC Alvaro to optics lab
18:26 UTC Betsy and Travis to end Y to realign ETMY
18:33 UTC Ed to PSL enclosure
18:40 UTC TJ to optics lab
19:35 UTC Georgia back
19:47 UTC Filiberto to LVEA to install safety relay for SQZ laser interlock
20:08 UTC Betsy and Travis back
20:09 UTC TJ back
20:20 UTC Sheila to optics lab
20:30 UTC Ed and Jason back
20:31 UTC Sheila back
20:31 UTC Nutsinee back
20:53 UTC Travis and Betsy to end Y
21:01 UTC Richard to LVEA
21:10 UTC Alvaro back from optics lab
21:29 UTC Jason and Ed to PSL enclosure
21:44 UTC Peter to PSL enclosure
21:44 UTC Nutsinee to ISCT6
21:56 UTC Greg to LVEA to turn on TCS laser power supplies
22:04 UTC Filiberto to CER
22:09 UTC Greg back
22:10 UTC Alvaro to optics lab
22:15 UTC Mark to mid Y
22:42 UTC Gerardo to mid Y to connect Inficon gauge to ADC for PT-245
22:48 UTC Filiberto done
23:43 UTC Ed back
00:09 UTC Betsy and Travis back

VIP final notes from optics lab and photos

Terry and I finished the final output paths of on the VIP last week and monday.  The last thing that we checked with laser beams on the platform was adjusting the alignment through the Faraday to reduce the misalignment caused by moving the lens translation stage from one extreme of its range to the other.  Alvaro helped us to check this using an iris about a meter away from the platform, when we started the beam was about 5mm lower with the translation stage at it's closest position to the Faraday than at its furthest.  After we adjusted the pointing into the Faraday the beam still moves vertically up by about 1 mm as the lens is moved from the closest position to the Faraday to the furthest from the Faraday.  

In the squeezing output path, we installed the dichroic 182mm from the edge of the OPO box, which means it is just over 226mm from the AR side of M1 to the dichroic.  We placed the dichroic (labeled DM1 on page 6 pf D1500302-v5) in about a half inch further from the OPO than was done at LLO to avoid mechanical interferences between our waveplate mounts.  The ROC=+50mm lens (E1600300) is 350 mm from M1, (122mm from the dichroic DM1). 

The next steering mirror labeled DM2 on page 6 pf D1500302-v5 is actually not a dichroic, but HR for 1064 (LLO had one more dichroic than we did), and it is 172mm from the dichroic DM1.  

The ROC=+150mm lens on the translation stage is 498 mm from the steering mirror DM2, which means it is 900 mm from M1 when it is in the center of its range.  

I've attached some photos of the VIP after Alvaro and TJ added cables and balanced it.  I tried to give names to the photos that I think are most useful, including ones that show the settings on the waveplate rotation stages.  

The CLF and green pump path waveplates were set to minimize the appearance of modes from horizontally polarized light in OPO scans.  The one at the input to the Faraday isolator was set to maximize transmission of the IR through the OPO to the output of the Faraday, and the waveplate directly after the Faraday rotator was set to maximize transmission using the beam used to test the Faraday.  

ETMy realignment (this time to the correct OpLev beam, we hope)

Betsy and I worked today on realigning the ETMy SUS to the correct OpLev beam as indicated by PCal and TMS reflections.  This involved the Quad-typical, many-many iteration adjustment of the both the main and reaction chain, OSEMs, EQ stops, and so on.  We eventually converged on a happy suspension and took a few very preliminary TFs that look reasonable.  We'll take a full set of TFs on Monday morning as the other teams are gearing up for their work in that chamber.  

Best guess explanation for SQZ beam diverter scattered light problem at LLO, and proposed solution for LHO

Peter, Lisa

(same entry as  LLO log entry 37917)

Following up the discussion we had at the ISC meeting today about the scattered light peaks in DARM at LLO when the SQZ beam diverter is closed, Peter pointed out that the black glass used on the back of all of the beam diverters is not coated, so there is probably no good reason to believe that the reflectivity is much lower than that of uncoated glass, R=8%.

So we went back and look at HAM6 drawings and pictures, and the most likely explanation is that we are simply sending some light from the beam diverter toward the region of HAM6 where OM2 and the HR in the OMC transmission path is, and light can easily find a path to the OMC. So, it seems that the simplest thing to do at LHO is to put a beam dump to catch the reflection off the beam diverter black glass.

SR3 Heater Driver Chassis

Completed in-rack cabling for the SR3 Heater Chassis D1700493 in the CER. Power, ADC, and DAC cables are now connected. The field cabling to the chamber (thermocouples and heater cable) were left disconnected. Chamber side is still missing connector for vacuum feed-through.

New SDF Overview screen

I have modified SDF_OVERVIEW.adl to modularize each node (using composite objects calling a new SDF_NODE.adl file)

Following the guardian overview scheme, the nodes are arranged by chamber/location or by subsystem. A link to the original screen has been added above the legend box.

 

Started stopped EY Beckhoff SDF systems

I restarted h1sysecaty1plc[1,3]sdf following this mornings PLC restarts at EY. Instructions on how to do this are now posted in the wiki"

RestartBeckhoffSDFSystems

fiber feedthroughs for HAM6

Terry, Alvaro, TJ and I tested the fiber feedthroughs after bagging up enough parts in the optics lab to create space on the table. 

We used 1064nm light coupled into our class B fiber to test the feedthroughs and the class A fibers which TJ and Alvaro placed on the VIP yesterday. 

We measured 92% transmission through the feedthrough SN8.  We connected this to the fiber SN6 which Alvaro and TJ had connected to the CLF collimator, we measured a total transmission of fiber SN6 + feedthrough SN8 of 82%.  (So the transmission of fiber SN6 is 89%)

Second we tested feedthrough SN9, with a transmission of 84%, and plugged this into fiber SN7 which is routed to the green collimator on the VIP, and measured a transmission of 87% (total transmission of feedthrough + fiber is 73%). 

I've added these results to E1700235 and created version 7.  

Adding Viton Beneath Balance Masses of H1 OPO (an OPOS) Reduces Broadboard Bending Mode Qs by a Factor of 2-3

Á. Fernández, J. Kissel, T. Shaffer

Álvaro, T.J. and I B&K hammered the optical parametric oscillator suspension's (OPOS) fully-payloaded bread board today, both with and without viton beneath its balancing masses. The reduction of bending mode Qs was about a factor of 2 to 3. Not very impressive -- my feeling is that we're either (a) putting viton where there is little bending, and/or (b) the balance masses do not provide enough moving mass at these mode frequencies to really suck out the mode energy through the viton.

I've not been tied close enough to this suspension to know if there is further action / improvement to make or take. Are there specific requirements we're trying to meet? Comment below if you have.
(Note, these results show that traditional, yet often broken, requirement of "Anything attached to the HAM-ISI must have its first bending mode resonances above 150 Hz" has been meet. Also, the addition of viton does not and will not have any affect on what ~1 Hz ISI - OPOS plant interaction issues Arnaud saw in LLO aLOG 37394.)

I attach the transfer function results.

We struck the platform vertically down at the outer edges, in the +Transverse corner and in the +Longitudinal corner (see E1700390 and/or G1300086 for basis definitions), and measured the response with the usual three-axis accelerometer. I only show the vertical response to each vertical excitation. 

Stay tuned for pictures. 

I attach the raw data (.pls files), the exported data (.txt files), and the script used to analyze the data.

70W progress Thurs 22

Maik, Jason, Matt

 

Semi frustrating day today. However we have:

• rewired the additional flow sensors and confirmed that they now readout.
• connected up the frankencable and the associated power meter and PD and confirmed that everything reads out in Beckhoff
• Hooked up the FE pickoff and confirmed it reads out in Beckhoff.
  • We could not connect the pickoff into the FE, as at LHO, both EOM ports are currently "connected", which was not the case at AEI or LLO (we used the non-used EOM port for the installs at the other sites). We (Maik/I) need LHO PSL people to decide if both are being used or if one is just a bonus that we can actually use, or perhaps we can try to use the AOM port.

 

We also could not test the mechanism for the new external shutter, as the mechanism is currently just bare wires and so we need to get the pinout to wire up a connector (this wasnt the case at LLO as it already had the connectors wires)

And we are having the issues with the diode chiller that we still havent been able to rectify.

   The new diode chiller could be run from local control with no apparent problems. However, it would not start from Beckhoff. It appeared to Beckhoff that the chiller was still on. Several things were tried but could not get the chiller to start from Beckhoff. 

    This morning, the diode chiller controller from the old chiller(Gromit)was installed in the new chiller (Wallace). On power up, the diode chiller started without command input, which it should not do. We stopped and started both chiller from Beckhoff several times and both appear to be working correctly.

  I will contact the manufacture of the faulty controller for repair or replacement.    

h1ecaty1 EPICS IOC not responding

looks like all slow controls epics channels from h1ecaty1 stopped working at 15:55 PST. Unless anybody needs these channels we will wait until tomorrow to restart.

Restarted.

EY ECAT PLC1 and PLC3 SDF appear crashed. I don't know how these get restarted.

Swap PSL Chillers

   Swapped the running chiller (Gromit) with the backup chiller (Wallace). No problems encountered with the swap or during the initial run-up. Ran Wallace for about 20 minutes to due leak checks and top up the reservoirs. The chiller is off right now, and is set for remote start control. 

   Will prep Gromit for warn stand-by backup.  

   Close WP #7338    

BSC1 ITMY OSEM signal fix, logistical details

This morning, Kyle and Bubba finished removing the door to BSC1.  I entered the chamber and began poking the ITMY R0 Right BOSEM cable from the OSEM connection out through the structure to the Table Cable Bracket.  No change.  I then also tried all of the following which produced no improvement to the spectra:

- Reseating the cable in the Table Cable Bracket

- Unbundling the cables that were secured to the upper structure leg

- Reseating the cable on the BOSEM itself

- Swapped the RT cable with the Side - problem went away - which meant that the problem was the BOSEM itself.

Removed BOSEM from structure and attempted to find short on the unit - no luck.  Swapped unit which meant removing it from it's adjustment bracket and rebuilding before reattaching.

Once back on the structure found it was OK.  Set OLV and 50% flag setting.

Cleaned flooring, removed tools, looked for cable routing issues in case I undid some other nice work.

Left chamber.  Kissel ran a few TFs which showed healthy.  Fil checked for HIPOT on the ESD connection and started another rounf of ground loop checks.  Tacked up door.

 

Pictures of BOSEM to aide discussion.