Another picket fence issue at 03:37 UTC, I think the third in the past few weeks. I restarted the process on nuc5.

Sun Apr 28 10:09:35 2024 INFO: Fill completed in 9min 31secs

Lockloss @ 16:50 UTC - link to online lockloss tool

Looks like ETMX had a glitch/saturation immediately before the lockloss (also seen by LSC-DARM), but otherwise I don't see an obvious cause.

TITLE: 04/28 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 143Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 8mph Gusts, 5mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.15 μm/s
QUICK SUMMARY: One lockloss early this morning at 12:01; H1 was able to relock on its own. Now locked and observing for almost 2 hours. Planning for coordinated calibration sweeps with L1 at 18:30.

• Wind and microseism are moderately low
• All other systems nominal

TITLE: 04/28 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 5mph Gusts, 2mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.11 μm/s
SHIFT SUMMARY:
Very quiet night.
The Wind is dieing down finally.
H1 Has been locked for 12 Hours and 12 minutes, and Observing.

BRS Drift Trends--Monthly Famis 26442

Trends go all the way back to Febuary which is when we let air into the vacuum chamber, so the ETMY Damp CTRL signal does make sense for that time frame in Febuary and early March.
BRSX has a few interesting spikes, April 2nd or 3rd Jim was adjusting the mass adjuster pico meter.
March 6th & 7th ish there was  some BRSX work & computer restart due to BRS not damping .

But Both BRS X & Y are within range!

A PCAL EndX Station Measurement was done on April, the PCAL team(    
 Dripta B. & Tony S.) went to EndX with Working Standard Hanford aka WSH(PS4) and took an End station measurements.
The EndX Station Measurement was carried out according to the procedure outlined in Document LIGO-T1500062-v15, Pcal End Station Power Sensor Responsivity Ratio Measurements: Procedures and Log.

Measurement Log
First thing they should have done was take a picture of the beam spot before anything is touched!

Martel:
Martel Voltage source applies voltage into the PCAL Chassis's Input 1 channel. We record the GPStimes that a -4.000V, -2.000V anhttps://alog.ligo-wa.caltech.edu/aLOG/uploads/77467_20240427213103_SPot.jpgd a 0.000V voltage was applied to the Channel. This can be seen in Martel_Voltage_Test.png . We also did a measurement of the Martel's voltages in the PCAL lab to calculate the ADC conversion factor, which is included on the above document.

Plots while the Working Standard(PS4) is in the Transmitter Module during Inner beam being blocked, then the outer beam being block, followed by the background measurment: WS_at_TX.png.

The Inner, outer, and background measurement while WS in the Receiver Module: WS_at_RX.png.

The Inner, outer, and background measurement while RX Sphere is in the RX enclosure, which is our nominal set up without the WS in the beam path at all.:  TX_RX.png.

The last picture is of the Beam spots after we had finished the measurement.

All of this data is then used to generate LHO_EndX_PD_ReportV2.pdf**** which is attached, and a work in progress in the form of a living document.

All of this data and Analysis has been commited to the SVN :
https://svn.ligo.caltech.edu/svn/aligocalibration/trunk/Projects/PhotonCalibrator/measurements/LHO_EndX/

PCAL Lab Responsivity Ratio Measurement:
A WSH/GSHL (PS4/PS5)FrontBack Responsivity Ratio Measurement was ran, analyzed, and pushed to the SVN.
The analysis of this measurement produces 4 PDF files which we use to vet the data for problems.
raw_voltages.pdf
avg_voltages.pdf
raw_ratios.pdf
avg_ratios.pdf

Obligitory BackFront PS4/PS5 Responsivity Ratio:
PCAL Lab Responsivity Ratio Measurement:
A WSH/GSHL (PS4/PS5)BF Responsivity Ratio measurement was ran, analyzed, and pushed to the SVN.
The analysis of this measurement produces 4 PDF files which we use to vet the data for problems.
AlphaTrends
raw_voltages2.pdf
avg_voltages2.pdf
raw_ratios2.pdf
avg_ratios2.pdf

This adventure has been brought to you by Dripta B. & Francisco L.

TITLE: 04/27 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 148Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 23mph Gusts, 14mph 5min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.11 μm/s
QUICK SUMMARY:
Wind speeds are elevated, but H1 has been Locked and Observing for over 4 hours.
Robert has an accelerometer line going through the Hallway, out the door and across the road. Please dont drive down Y arm until after the cable has been removed sometime tomorrow.

TITLE: 04/27 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
INCOMING OPERATOR: Tony
SHIFT SUMMARY: One lockloss and an earthquake this shift, but otherwise a quiet one. Since neither H1 nor L1 were locked for the scheduled 18:30 UTC coordinated calibration sweeps, we have postponed them until tomorrow at the same time.

• 16:50 - Incoming EQ from Christmas Island
• 17:18 - Lockloss (alog77463)
• 17:33 - EQ mode activated while relocking
• 18:47 - Reached NLN
• 18:49 - Started observing

H1 has now been locked for 4 hours.

LOG:

Lockloss @ 17:18 UTC - link to online lockloss tool

There was a M6.1 quake from Indonesia incoming at the time, although I don't immediately see evidence that ground motion caused this lockloss.

Sat Apr 27 10:10:32 2024 INFO: Fill completed in 10min 28secs

Fri Apr 26 10:10:46 2024 INFO: Fill completed in 10min 42secs

Jordan confirmed a good Friday fill curbside.

TITLE: 04/27 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 149Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 3mph Gusts, 2mph 5min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.12 μm/s
QUICK SUMMARY: Looks like H1 lost lock around 6 hours ago from a M6.5 EQ from Japan and Oli was able to help it back up. H1 has been locked and observing for 3 hours.

• Microseism is trending down and wind is low
• All other systems nominal

There was a drop in clean range around 5:20 this monrning, which doesn't seem to be a reapeat of the output arm shift we had earlier this week. 

Attached is a trend of the DARM blrms (based on DARM error, no calibration corrections or cleaning) and comparison of the cleaned and corrected range against the CAL-DELTAL range, only the cleaned channel sees the drop.  This made me concerned that we had a drop in optical gain, but the trend of the time dependent calibration correction factors doesn't show anything happening at this time. 

I don't know what would cause a sudden change in the clean range, since I don't think that the jitter subtraction would cause a sudden change like this.

H1 Manager called because it couldn't get ALSY to lock in initial alignment. The flashes were barely below being able to catch. I paused INIT_ALIGN and touched ALSY in yaw and we were able to lock green and are on our way back up.

TITLE: 04/27 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY:
H1 is locked and Observing for 4 Hour now.
Relatively quiet night.
 

LOG:
No log

FAMIS 26297

H0:VAC-MX_FAN1_370_2_ACC_INCHSEC has a very Strange looking reoccuring ingrease in its noise.
It looks like this fan wasn't being used until about 100 days ago. 100 days ago it seemed to be fairly noisy as well, but this is strange looking and very different.
it seems like the fan is noisy for 12-16 ish hour and quiet for 8-16 hours. Maybe this particular fan isnt on for 8 hours,
It's likely it turns on at 1Pm and turns Off at 9-10 pm.

I think this is a new noticable development since the last time I checked on the Vibrometers.

TITLE: 04/27 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.17 μm/s
QUICK SUMMARY:

00:52 UTC Intentional Drop from Observing to adjust squeeze angle.

Requested SQZ_MANGER to go to SCAN_SQZANG saw the phase slider move around a bit and it created https://lhocds.ligo-wa.caltech.edu/exports/SQZ/GRD/SQZANG_SCAN/SQZANG_SCAN_240426175458.png

00:56 UTC Back to Observing

2:04 UTC  Lockloss  https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi?event=1398218686

Unknown cause but ETMY L2 Master out starts to change behaivor about a second before the lockloss.

---Relocking--
Increase flashes ran for YARM
Happened automatically without any input from me.
Nominal_Low_Noise reached at 3:01 UTC
Observing reached at 3:04 UTC

Ibrahim A, Oli P, Mark B, Betsy W

Context:

M3 on the beam splitter has secondary prisms that are placed along the barrel below the primary prisms. These secondary prisms are placed at a location below the primary prism, and if placed in the correct spot, act as a clamp, damping the oscillations moving down the wire loop into the optic. We've been working on finding the optimal secondary prism position for the BBSS.

Experiment:

The experiment for determining this position was developed for the BSFM in 2011(T1100086), and we used a similar setup for our three (successful) runs for the BBSS. This is basically how the experiment is set up to work:

1. A biased solenoid is placed a few millimeters away from one of the M2-M3 loop wires. The solenoid is driven at the wire’s predetermined resonance frequency using a waveform generator.
2. The wire goes from M2 down through M3’s fixed primary prism and (the reason for this experiment) moveable secondary prism.
3. Phonograph needle is rested on wire below the secondary prism and the other end is connected to a spectrum analyzer. Five FFT averages are taken to give us an attenuated peak at the resonant frequency. This is a reading. We took 4/5 measurements for each location, where each measurement consisted of five 8-second averages.
4. We move the prism down by a millimeter or two and take more readings.
5. From the results, we determine the lowest amplitude peak/highest attenuation and note the prism position.
6. This becomes the new BBSS secondary (glued on) prism position.

Results + Commentary:

Note: Mark has an upcoming alog about the run of data and issues that we took when he was here, but in LESS IMPORTANT Auxiliary Investigations we will be focusing on the data from the second and third runs, but here in the results will still be showing the data we got with him.

The plot attached shows the attenuation measured versus the position (positive distance relative to the mass’ centerline) of the secondary prism. Each color is a separate run, and the more negative the attenuation, the quieter the reading was, so we are looking for a location with the lowest values where the secondary prism would do the most damping.

We found that there is a region between ~29.00mm and ~31.5mm below the horizontal center of the mass where the amplitude is minimized. There are approximately three anomalous data points in between, with one confirmed being due to cross-coupling of above wire. As of now, we’re still working on understanding this data and have spoken to Mark B and Jeff K about how we can go about accurately interpreting the raw data (including essential questions about the calibration and setup. See below.)

LESS IMPORTANT Auxiliary Investigations - Details, Details, Details

    Read for Clues/Hints (things we noticed, changed etc.):

• Mass Locking: When Mark Barton was at LHO, we “almost locked” the Test Mass in order to help damp any motion that we caused when we adjusted the experiment for a new reading. This locking was not meant to take the load off the wires but we realized that given differing amounts of “just touching”, our attenuation amplitudes changed by over 20dB systematically. Importantly, the attenuation difference did not change the resonant frequency, which is what really matters. Given this, we proceeded with an “almost locked” Dummy Test Mass.
• Cross Coupling: The expected behavior for this experiment is that there is a minimum/dip in the resonant frequency amplitude where we can optimally glue the secondary prism. At certain positions along this trend however, we noticed a marked and visible vibration in the wire. Upon further investigation, we found that the wire segment directly above it (Top Mass - PUM) was also visibly vibrating. Upon meeting with Mark and checking records, we found that this was more than likely an nth harmonic of that upper wire causing cross-coupling. Thus, these “anomalous” positions should be avoided.
• Needle Changes: One of the three data sets we have was taken with a different needle because the one used for the first run had broken, and we had another needle become permanently cocked out of place and give us erroneous readings before we swapped the needle again and were able to get a good second and third run. We took “no contact” or noise floor measurements for each new needle. The noise floor measurements for each run were taken and we are working on calibrating the two needle sensitivities to better represent our data.
• Needle Touching: We tried to see if there was an effect in noise with the needle touching head on vs. on the side of the wire. We found that while the location of the needle on the wire didn’t really matter, the amount of tension between the needle and the wire does add some damping to the wire. As such, we attempted to ensure that the needle was resting on the wire rather than applying any force to it. We also tried to replicate the location/contact area of the needle for consistency.
• Cable Changes: We noticed that moving BNC cables too close together or having them sway in the cleanroom air contributes to noise. To tackle this, we used small weights to secure them to the ground and separated them as much as possible.
• Solenoid Distance Changes: For unknown reasons, and despite our wave function generator having the same output throughout, the wire would vibrate visibly at certain times than others for the same frequency. After playing with certain distances, we landed on the original 2.5mm for the sake of consistency. An effect we did notice is that if the solenoid was actuating too strongly, it would move the wire laterally back and forth with some oscillatory behavior. This would move the entire mass. At our 2.5mm, we tried to ensure that the wire was still visibly vibrating but not so much as to cause translation movement in the masses or the wire.
• Resonant Frequency Experimentation (Largest Persistent Confusion):
  • Mark gave us this suggestion to see the effect of frequency changes on the wire for different prism positions. We realized that when we sweep the frequency over +-2Hz, there was definitely more oscillation in some points than others. This was the case for each position we tried. I.e. The resonant frequency of the wire changed slightly as the prism moved down (and even just with a prism in vs. without), and as such, the actuation frequency from the solenoid was not (and could not have been) exactly at the resonance of the wire. 
  • What is confusing to us here is that if the entire point of the experiment is to shake the wire by some constant amount to measure the attenuation below the prism, how can we be sure that this attenuation is maximized if the amount that the wire is shaken changes and in fact, depends on the prism position? (by virtue of the res. Freq. moving slightly by each move).
    • E.g. At position 16, the wire was vigorously shaking (due to coupling) so obviously our reading was just … louder.
    • E.g. At position 18, the wire was so far away from the attenuation frequency that it was not moving at all so obviously our reading was just … quieter. We spanned the frequency at the same actuation strength and found that the resonant frequency had moved all the way from 303 to 307 Hz - so obviously the wire isn’t resonating/shaking things as much.
  • We tried taking readings where we just match the visible vibration at each prism point but quickly realized that this would just yield us the same results each time because it tells us nothing about the attenuation of the actual resonant frequency we want to damp just how good this prism system was at damping any vibration. 
  • With 2 needles, this effect would be negated because we could just take signal A and signal B and compare the attenuation before and after the prism. We have the tools for this if it is worth doing.