Today's activities:
- HAM3 Annulus Ion Pump was restarted
- The 1000 amu RGA's gate valve was leak checked - all is good
- On BSC8, 2 pcs. of 16.5" blanks have been torqued (at the northern side), so there is only 1 left to be replaced (at the southern side)
- The EX RGA was wrapped, and is ready for bakeout, which will happen tomorrow
- EX pumpdown status: it is at 1.1E-7

Sheila, Rahul, Camille, Julian, Naoki

After ZM4 and ZM5 PSAMS offload in 75677 and 75709, we aligned ZM4/5/6 with seed and successfully offloaded the DAC outputs of ZM4/5/6.

Fig 1 and 2 show the ZM slider values before and after our alignment work.

Before moving ZMs, first we checked the alignment of two irises in HAM6 and HAM7. The irises in HAM7 were OK, but the irises in HAM6 were not centered, so we moved SRM to center two irises in HAM6. 

Fig 3 and 4 show the SRM slider values before and after our alignment work.

After the SRM alignment, the H1:ASC-AS_C_NSUM_OUT16 was around 0.2 with 36dB whitening gain and 80 of H1:SQZ-RLF_QPD_A_SUM. 

For yaw, we reduced ZM6 yaw from 489 to 390 and compensated the alignment of two irises in HAM6 by ZM4. Since the DAC output of ZM4 got large, we made the ZM4 yaw slider value 0 and mechanically offloaded the ZM4 yaw.

For pitch, we reduced ZM6 pitch from 1072 to 0 and compensated the alignment of two irises in HAM6 by ZM4 and ZM5. After that, two irises in HAM7 were not centered anymore so we moved the height of two irises in HAM7. Since the DAC output of ZM4 and ZM5 got large, we made the ZM5 pitch slider value 0 and mechanically offloaded the ZM4 and ZM5 pitch.

We will measure the beam profile in HAM7 tomorrow.

TITLE: 02/05 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: Main activities today were HAM7 beam alignment work with more to come tomorrow, the TCS water lines were filled and chillers are running again; LVEA is still laser hazard.
LOG:

WP 11671
SUS HAM 5-6 System Wiring Diagrams D1002740
Grounding and Shielding at LIGO T1200131

The following cables were checked for ground loops:

SUS_HAM6_010 (OMC Top/Left)
SUS_HAM6_011 (OMC Right/Side)
ISC_236 (OM1)
ISC_237 (OM2)
ISC_238 (OM3)

No shorts found. All pins open to ground. Pins 13 tied to shell. HAM 5-6 System Wiring Diagrams D1002740-v10 used as reference. See alog 75684, for details on testing of ISC ground loops done by keita.

Mon Feb 05 10:05:50 2024 INFO: Fill completed in 5min 46secs

Travis confirmed a good fill curbside.

FAMIS 20014

There looks to have been a change in chiller water flow about a week ago, seen by several flow and temperature channels.

TITLE: 02/05 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: USEISM
    Wind: 13mph Gusts, 10mph 5min avg
    Primary useism: 0.08 μm/s
    Secondary useism: 0.68 μm/s
QUICK SUMMARY:

• LVEA laser hazard work today in HAM7 (HAM6 to follow, possibly later this week)
• More leak checks with TCS water lines
• EX is pumping down
• Crane inspections have been pushed off until next week at earliest

Robert, Mitchell, Corey, Tony, Betsy, TJ, and Alena, Eddie and the SLiC team

In O4a, scattering noise at or near the current DARM noise floor was likely produced by 3 sources in the input MC tube (74772). The most important source was the MC baffle by HAM3, followed by the MC baffle by HAM2. I think that the main reason these two baffles produced scattering noise is that they were not angled enough and so they retro-reflected light scattered from certain optics as well as reflecting light between optics. To mitigate this, we increased the angle of these two baffles from 5 to 10 degrees (75637, 75654). We also increased the damping of both baffles in order to reduce the cutoff frequency of scattering shelves.

In addition, the beam tube itself might have been producing scattering noise associated with its axial resonance of 15.2 Hz (Fig. 1).  Because of this possibility, we installed nozzle baffles in all MC-tube nozzles that have blank-off flanges (15 total - 75654 ). Blank-off flanges are generally the most problematic nozzle equipment because they cover the whole nozzle and the circular milling groves retro-reflect some of the incident light from a wide range of angles. We also installed two nozzle baffles in the upper two ports of the +Y door of HAM3 (last page of Fig. 2).

Finally, we installed an unplanned baffle to hide a portion of the MC-tube wall that was likely retro-reflecting light scattered from MC3 (75688). This glint was identified in beam-spot photos, photos that are taken and illuminated  from near the beam spot locations on the optics.

Figure 2 shows beam spot photos taken from the point of view of each of the six optics before and after the mitigations. There were some auto-focus problems with some of the "before" pictures. Some of the photos are annotated with features and possible problems.

Figure 3 shows the damping of the two MC baffles

Sun Feb 04 10:06:59 2024 INFO: Fill completed in 6min 55secs

Two systems stopped running overnight:

HWS-EY: computer crashed at 03:07 Sat 03feb2024 PST. This is the cause of the EDC's 86 disconnected channels. h1hwsey is not pingable, but its IPMI port is working.

Picket Fence: the server on nuc5 stopped updating at 21:53 Fri 02Feb2024 PST, the IOC continues to run with flatlined channels.

Both can wait till Monday for restarts and investigations.

Sat Feb 03 10:05:48 2024 INFO: Fill completed in 5min 44secs

Before heading home yesterday, I checked the open chambers, and noted that the C3 covers were not billowing out as per the usual "weekend setting", HAM6 looked good.  I spoke to Keita K., Vicky X. and Betsy W. about the lack of purge air.  I was given the green light to increase the purge air in HAM7.

Today's activities:
- HAM3 Y+ door was reinstalled. No issues during the process, however, some scratches have been found - see pics.
- After the door was reinstalled, the Annulus volume is being pumped
- The Gate Valve for the 1000 amu RGA was installed on the Y-mainfold, with an additional angle valve
- 2 out of 3 16.5" 3IFO feedthrus were removed from BSC8 - at the north side. A very scratchy conflat was found, see pic. To mitigate the risk, Technetics-Helicoflex-type CF seal repair gaskets will be ordered. At the south-side of the chamber, the unnecessary cable trays were removed, in preparation for the 3rd feedthru removal
- EX pumpdown status: it is already at ~2E-7

Julian, Sheila, Vicky, Camilla. After today's alog 75677 ZM4 PSAMs offloading. WP11666

Started with ZM4 sliders at Pit  -362, Yaw -273. Our beam off the OPOS was good, centered on both HAM7 QPDs with nsum 150 to 160.

The beam was off mainly in yaw, centered on irises by moving sliders to Pit -521, Yaw -1213. This was with PSAMS at 200V. There is still loads of range on the sliders, DAC counts up to 27,000 out of 500,000.

We watched the beam and ramped PSAMS from 200V to 0V over 30s, the beam may have moved slightly higher. 

Leaving both ZM4 and ZM5 PSAMS at 0V for tomorrows work.

The dust monitor IOC was restarted this morning by Dave which can reset the alarm levels. Following document E1600132, I confirmed that the alarms levels are still set properly, The CS dm alarms, 5, 6 & 10 are set to the "Class-100" (major alarm at 100 counts for both 0.3u and 0.5u as opposed to their normal 10000 for 0.5u and 7000 for 0.3u) as defined in the document since these monitors are by vented open chambers. Once the chambers are closed back up I'll put the CS dm alarm thresholds back.