Closes FAMIS#26018, last checked 81331

Nothing looks out of the norm

Yesterday Gerardo noticed that the south most section of the EY wind fence had some broken cables on the lower half of the fence on the panel we did NOT replace last summer. I think we have a couple of ways we could go about repairing this. We will discuss options, but the weather is not great for this kind of work.

Fri Nov 22 10:10:42 2024 INFO: Fill completed in 10min 39secs

Gerardo confirmed a good fill curbside through the tumbleweeds. Minimum TC temps are getting close to their trip temps (trip=-100C, TCmins=-117C,-115C). I have increased the trip temps to -90C for tomorrow's fill. Looking at a yearly trend, we had to do this on 25 Nov last year, so we are on schedule.

On Tuesday NOV 19th Eric started the replacement of the ceilign light fixtures in the PCAL Lab.
Francisco and I grabbed 3 HAM Door covers to stretch out over the PCAL table to minimize dust particles on the PCAL optical bench.
I also put all the Spheres away in the cabinet and made sure that they all had their apature covers on.
I went in to shutter the laser using the internal PCAL TX module shutter, and the shutter stopped working.
I then just powered off the laser, removed the shutter, and repaired the shutter in the EE lab.
Put in an FRS ticket: https://services1.ligo-la.caltech.edu/FRS/show_bug.cgi?id=31730
The Shutter is repaired and just waiting for the FAC team to finish the Light fixture replacement to reinstall.

Update: Friday NOV 22nd, there are 2 more light fixtures in the PCAL LAB that need to be replaced. One directly above the PCAL Optics table.
PCAL Laser Remains turned off with the key out. 
 

Obviously, lots of reds and zeros due to ongoing NPRO work.
Laser Status:
    NPRO output power is 1.839W
    AMP1 output power is -0.6214W
    AMP2 output power is 0.07093W
    NPRO watchdog is GREEN
    AMP1 watchdog is RED
    AMP2 watchdog is RED
    PDWD watchdog is RED

PMC:
    It has been locked 0 days, 0 hr 0 minutes
    Reflected power = -0.4062W
    Transmitted power = -0.02552W
    PowerSum = -0.4317W

FSS:
    It has been locked for 0 days 0 hr and 0 min
    TPD[V] = -0.01703V

ISS:
    The diffracted power is around 4.0%
    Last saturation event was 0 days 22 hours and 52 minutes ago

Possible Issues:
    AMP1 power is low
    AMP2 power is low
    AMP1 watchdog is inactive
    AMP2 watchdog is inactive
    PDWD watchdog is inactive
    FSS TPD is low
    Service mode error, see SYSSTAT.adl

TITLE: 11/22 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Corrective Maintenance
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 15mph Gusts, 9mph 3min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.30 μm/s
QUICK SUMMARY:

H1 is DOWN due to continued work for another PSL NPRO swap which continues.

Microseism has drifted beneath the 95th percentileover the last 24hrs.  Winds are somewhat low and it was a rainy drive in.

J. Oberling, R. Short

Since we've convinced ourselves that the new glitching is coming from the recently-installed NPRO SN 1661, we are swapping it out for our final spare, SN 1639F.  This is the NPRO originally installed with the aLIGO PSL back in the 2011/2012 timeframe; it was removed from operation in late 2017 (natural degradation of pump diodes) and sent back to Coherent for refurbishment, and has not been used outside of brief periods in the OSB Optics Lab since.

We first installed the power supply for this NPRO and tweaked the potentiometers on the remote board to make sure our readbacks in the PSL Beckhoff software were correct.  We then swapped the NPRO laser head on the PSL table and got the new one in position.  The injection current was set for ~1.8W of output power; we need 1.945A for ~1.805 W output from the NPRO.  We test the remote ON/OFF, which worked, and the remote noise eater ON/OFF, which also worked.  We optimized the polarization cleanup optics (a QWP/HWP/PBSC triple combo for turning the NPRO's naturally slightly elliptically polarized beam into vertically polarized w.r.t. the PSL tabletop).  The power was turned down and the beam was roughly aligned using our alignment irises (with the mode matching lenses removed).  At this point we did a beam propagation measurement and Gaussian fit in prep for mode matching to Amp1.  The results:

• Horizontal
  • Waist: 176.0 µm
  • Position: -124.3 mm
• Vertical
  • Waist: 182.0 µm
  • Position: -169.3 mm
• Average
  • Waist: 178.8 µm
  • Position: -147.2 mm

Using this we got a preliminary mode matching solution in JamMT, using the same lenses we used for NPRO SN 1661, so we installed it.  I managed to get a picture before JamMT crashed on us, see first attachment.  Before tweaking mode matching we checked our polarization into Faraday isolator FI01.  We have ~1.602 W in transmission of FI01 with ~1.701 W input, a throughput of ~94.2%.  We then proceeded with optimizing the mode matching solution.  It took several iterations (7, to be exact), but we finally were able to get the beam waist and position correct for Amp1 (the target is a 165 µm waist 60mm in front of Amp1, or 1794.2mm from the NPRO):

• Horizontal:
  • Waist: 166.0 µm
  • Position: 1789.0 mm
• Vertical
  • Waist: 163.0 µm
  • Position: 1800.0 mm
• Average
  • Waist: 164.6 µm
  • Positoin: 1794.5 mm

To finish, we set up a temporary PBSC to check that the polarization going into Amp1 was vertical w.r.t. the PSL tabletop.  We put a power meter in transmission of the temporary PBSC and adjust WP02 to minimize the transmitted power; the lowest we could get is 0.41 mW (with a roughly 1.6 W beam) in the wrong polarization, which matches what we had during the most recent NPRO swap, so we were good to go here.  We forgot to measure the final lens positions before leaving the enclosure, we will do that first thing tomorrow morning.  The new NPRO is now set, aligned, and mode matched to Amp1 and we will continue with amplifier recovery tomorrow.

We left the NPRO running overnight with enclosure in Science mode; the first shutter (between the NPRO and Amp1) is closed.

TITLE: 11/21 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Corrective Maintenance
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: The IFO was down all day as the NPRO swap started today and is still ongoing as of 16:30.
LOG:                                                                                                                                                                                                                                                                                                                                                                               

• 19:40 UTC I brought SEI to maintenance
• 21:06 UTC Dave powered down the EndX models for the DAC swap
• 21:40 UTC The model was restarted and I recovered the SUS and SEI

Trending the new PSL HV monitor H1:PEM-CS_ADC_4_28_2K_OUT_DQ from alog81401

I've made a script that uses a la mode to double check the mode matching that Jason and Ryan are working on using Jammt , I'm posting it here so that people can use it in the future if they want to.  It is saved in sheila.dwyer/PSL/modematching  along with a copy of the a la mode code (alm).

I took the beam profile measurements that they saved in /ligo/gitcommon/labutils/beam_scans/Data/NPRO_a_21Nov2024.txt and used them for fitting.   In this text file the distances are a rail location, I used the information in 80895 and compared it to what I got by fitting the data in NPRO_26Oct2024.txt to find the offset between their rail distances and their coordinate system. 

From their data I get a horizontal waist at 162.1um at -0.097 meters, and a vertical waist of 182.1 um at -0.176 meters (see first attachment).  This is more astigmatism than the laser 1661 had.  If no mode matching had been done at all with this NPRO swap we would end up with an overlap of 87% to amp1 (sqrt(X overlap* y overlap)).

I used the average of the vertical and horizontal waist locations, and asked a la mode to optimize lens 2 + 3 for that average waist (as Jason and Ryan were only planning to move lens 2 + 3 to avoid changing the waist through the EOM).  Then using that lens solution to propagate the fitted x and y waists, the overlap given by sqrt(Xoverlap * Y overlap) for that solution is 95% for lens locations of:

    label    z (m)     type    parameters         
    -----    -----     ----    ----------         
    L1       0.1020    lens    focalLength: 0.2220
    L2       1.1511    lens    focalLength: -0.334
    L3       1.2787    lens    focalLength: 0.2220

This is in pretty good agrement with the photo that Jason sent me of their Jammt solution. I also plugged in their solution, and get an overlap of 94%:
 
    label    z (m)     type    parameters         
    -----    -----     ----    ----------         
    L1       0.1020    lens    focalLength: 0.2220
    L2       1.1440    lens    focalLength: -0.334
    L3       1.2780    lens    focalLength: 0.2220

Using the lockloss page, I picked out some times when the tag "IMC" or "FSS_OSSCILATION" was triggered. Then, I just made some simple time series comparison plots between several PSL channels and PSL PEM channels. In particular, the PSL channels I used were:

H1:PSL-FSS_FAST_MON_OUT_DQ, H1:PSL-FSS_TPD_DC_OUT_DQ, H1:IMC-MC2_TRANS_SUM_IN1_DQ, H1:PSL-PWR_NPRO_OUT_DQ, H1:PSL-PMC_MIXER_OUT_DQ, H1:PSL-PMC_HV_MON_OUT_DQ. I compared those to the following PSL PEM channels: 

H1:PEM-CS_ACC_PSL_PERISCOPE_X_DQ, H1:PEM-CS_ACC_PSL_PERISCOPE_Y_DQ, H1:PEM-CS_ACC_PSL_TABLE1_X_DQ, H1:PEM-CS_ACC_PSL_TABLE1_Y_DQ, H1:PEM-CS_ACC_PSL_TABLE1_Z_DQ, H1:PEM-CS_ACC_PSL_TABLE2_Z_DQ, H1:PEM-CS_MIC_PSL_CENTER_DQ. For this analysis, I've only looked at 3 time periods but will do more. Below are some things I've seen so far:

1. I definitely do see correlations between the IMC/FSS (IMC_MC2_TRANS & FSS_FAST_MON)  channels and the PEM PSL sensors. In particular, it seems like the most consistent correlations are with the PSL_PERISCOPE_X/Y and PSL_TABLE1_X/Y/Z channels. In some cases, there was a visible glitch in PSL_TABLE2_Z, but the amplitude is much less than in the other PEM channels.
2. Some PEM glitches correlate with the glitching in PMC_HV_MON, but this was only the case for 2 of the 3 times I looked at.
3. Some PEM glitches correlate with PMC_MIXER, but I wonder if that is just a coincidence (see slide 9 for an example)
4. I have seen no obvious correlation with the PEM PSL sensor glitches and the NPRO_PWR channel.

From my very limited dataset so far, it seems like the most interesting area is where the PSL_PERISCOPE_X/Y and PSL_TABLE1_X/Y/Z channels are located.

The stem wall pour is completed, forms are stripped and it has been entirely back-filled. Weather has prevented the pour of the slab this week so Jake has shifted his attention to erecting the metal framework of the building. The forecast is not favorable for a slab pour tomorrow, so its likely to take place early next week.

T. Guidry

[Debasmita, Anamaria]

We wanted to check if there is any microseismic coupling at LHO, similar to that of LLO. So far, for LLO our understanding is that the microseismic ground motion (0.1-0.5 Hz) is being amplified by a potential scatterer which has a transfer function as shown in the first image. This transfer function was modeled based on some other information and seems to explain the LLO noise quiet well (LLO aLOG 73845). 

For LHO, we amplified the ground motion by the same transfer function and simulated the scatter shelf. If we assume that the scattered light amplitude is same as LLO (4e-10), given the amount of microseismic ground motion at LHO the scatter shelf falls below the current DARM spectra of LHO (second image). Even if we double the light amplitude, the scatter shelf does not show up above the present noise background (third image) but it comes quiet close to the noise floor.

But, if we double the microseismic ground motion and then further amplify it by the model transfer function, the scatter shelf shows up above the present DARM spectra (fourth image). This shows that, the same source which is producing the microseismic scattering at LLO can produce similar noise at LHO, but it will only be visible if the IFO is locked during a somewhat high microseismic motion. Even if the amount of light is half of what it is at LLO, the scatter shelf would still be visible if the ground motion is higher (fifth image). 

I used the ground motion as it was during 2023-12-06 11:00:00 UTC at LHO. This is one of the high microseismic days of LHO, the median of rms ground motion in 0.1-0.3 Hz was 689.66 nm/s and in 0.3-1.0 Hz was 95.02 nm/s. 

In the last image, I plot all the simulated traces together for a better visualization of how the light amplitude and amount of motion can modify the scatter shelf.  

WP12214

Marc, Ryan C, Dave:

h1susex has been fenced from Dolphin and powered down in preparation to re-establishing the LIGO DAC 28ao32 as the driver of the ETMX L1/L2 and ESD channels, essentially undoing what was done on Tuesday.

Fil is borrowing one of the PEM adc channels I was borrow for the Guralp 3T huddle testing. He unplugged one of the horizontal readbacks from the Guralp on ADC4, leaving the other 2 dofs plugged in. Channel he connected to is ADC 4 28, H1:PEM-CS_ADC_4_28_2K_OUT_DQ.

Thu Nov 21 10:11:56 2024 INFO: Fill completed in 11min 53secs

Sheila and I spent some time today trying to calibrate the PMC channels into units of frequency so we can compare the glitches seen by the PMC with other channels. Peter's alog comment last night (81375) leads us to understand the glitches are around 2 kHz in frequency, so above the PMC bandwidth. Therefore, we want to calibrate the PMC error signal.

Luckily for us, Jeff Kissel recently did some PMC scans to determine the PMC PZT Hz/V calibration for a different purpose, alog 73905 (thanks Jeff!). We used his DTTs to determine the time it took to scan one FSR, see screenshot. We determined that it took 0.52 seconds to scan one FSR, and the scan rate is approximately 6.75 V/s (we know the PZT is nonlinear, but we figure this estimate is good enough for our purposes). This gives us 3.51 V/FSR on the PZT, or 0.0236 V/MHz, using the FSR = 148.532 MHz from T0900616.

We are still thinking about how to calibrate the PMC mixer signal.

2024 Nov 12

Neil, Fil, and Jim installed an HS-1 geophone in the biergarten (image attached). HS-1 is threaded to plate and plate is double-sided taped to the floor. Signal given was non-existent. Must install pre-amplifier to boost signal.

2024 Nov 13

Neil and Jim installed an amplifier (SR560) to boost HS-1 signal (images attached). Circuitry checked to ensure signal makes it to the racks. However, when left alone there is no signal coming through (image attached, see blue line labelled ADC_5_29). We suspect the HS-1 is dead. HS-1 and amplifier are now out of LVEA, HS-1's baseplate is still installed. We can check one or two more things, or wait for more HS-1s to compare.