Jennie W, Elenna, Camilla, Mayank

Today we had a longer commissioning period so we could heat up the TSAMS on OM2 without causing glitches during oberving as the heat up happens, see alog #78618 for details of these.

Method

17:20:16 UTC Camilla and Mayank started heating up OM2 after losing lock. This prevented us from taking darm offset step measurements beforehand.

We took the first darm offset step at 19:24:10 UTC about 1 hr 41 mins into lock.

We were going to take a squeezed data set of FIS, FIAS and No SQZ but we lost lock while in FIS.

After we lost lock we started cooling down OM2 to its nominal state at 19:49:21 UTC.

Then we took the second DARM offset step measurement when we were almost at the nominal cool state, around 31 mins into lock.

DARM Offset Step Method

This measurement script turns all the PCAL lines off except 410 and 255 Hz and increases their amplitude so they show up very strongly in DARM.

Then the fringe offset is varied in the DC readout loop to change the controlled power level on the output DCPDs (which is nominally set to 40mA during NLN).

The two PCAL lines allow us to measure the optical gain of the interferometer as we change this output power and thus the carrier light coming from the arms to the output of the IFO.

Results

The data for the hot state is saved in /ligo/gitcommon/labutils/darm_offset_step/data/darm_offset_steps_2025_Jan_30_19_24_10_UTC.pkl

The analysed pdf showing the plot of DCPD sum power vs. optical gain, optical gain vs. darm offset, and power into HAM6 vs. DCPD sum power is saved in /ligo/gitcommon/labutils/darm_offset_step/figures/all_plots_plot_darm_optical_gain_vs_dcpd_sum_1422300272_Jan_30th__OM2_Hot_state_1_hr_41m_into_lock_.pdf

The contrast defect (taken from the first graph) averaged between the two calculations for each line is (0.211 + 0.177) / 2 = 0.194 +/- 0.064 mW.

The equation for anti-symmetric port power taken from the third graph

P_AS = 1.485*P_DCPD + 688.147 mW

The data for the cold state is saved in /ligo/gitcommon/labutils/darm_offset_step/data/darm_offset_steps_2025_Jan_30_21_30_34_UTC.pkl

The analysed pdf showing the plot of DCPD sum power vs. optical gain, optical gain vs. darm offset, and power into HAM6 vs. DCPD sum power is saved in /ligo/gitcommon/labutils/darm_offset_step/figures/all_plots_plot_darm_optical_gain_vs_dcpd_sum_1422307856_Jan_30th__cold_OM2_31m_into_lock.pdf

The contrast defect averaged between the two calculations for each line is(0.213 + 0.224) / 2 = 0.219 +/- 0.088 mW.

And the equation for anti-symmetric port power is

P_AS = 1.533*P_DCPD + 669.724 mW.

Analysis

This contrast defect of 0.2 mW is much lower than the previous measurement from October 2024 with OM2 cold which was around 0.7 mW. The contrast defect does not seem to change much by heating up OM2, this makes sense as the curvature of OM2 should not change the wavefront matching between the arms. I am unsure why our arms are better mode-matched to each other compared to October last year though.

The HAM 6 throughput for the TM00 mode in the hot state is 1/1.485 = 67.3 %, for the cold state it is lower at 65.2 %. Does this mean the interferometer mode-matching to the OMC is better in the hot state? Compared to the throughput calculated for the October measurement which was 82%, this implies the IFO/OMC mode-matching has decresed since October. The junk light at the anti-symmetric port is now around 679 mW which is an increase of (((688+670)/2)  - 656 ) / 656 = 3.5% compared to October. Further thinking/analysis needed.

TITLE: 01/31 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 154Mpc
OUTGOING OPERATOR: Tony
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 8mph Gusts, 4mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.32 μm/s
QUICK SUMMARY:

IFO is in NLN and OBSERVING as of 13:38 UTC (13:30 hr lock)

Getting some PI-24 ring ups that seem to have dropped us out of observing temporarily.

TITLE: 01/31 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
INCOMING OPERATOR: Tony
SHIFT SUMMARY: Observing at 155Mpc and have been Locked for 3.5 hours. Not sure what caused the lockloss earlier. Relocking generally went well - no issues with ALSX, but ALSY did look like garbage like it's been looking lately, but I noticed that although it looked like garbage, as soon as I went into an initial alignment it immediately locked, looked great and was very stable (ndscope1). Not sure if that's been the case every time but it was strange.
LOG:

00:30 Out of Observing due to SQZ unlocking
    - For some reason it looks like NO_SQUEEZING had been selected when it lost lock - seems like an accidental click? (ndscope2)
00:36 Observing

01:05 Lockloss
    - ALSY issues
    - Went to run an initial alignment and all of a sudden ALSY is looking great!???
    - No issues with ALSY after IA
02:33 NOMINAL_LOW_NOISE
02:36 Observing

Lockloss @ 01/31 01:05 UTC

TITLE: 01/30 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 159Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY:

Highlight of today was H1 being down for a 5.5hr Commissioning break, but it started with H1 down from a lockloss and there was a lockloss in the middle of this down time.

ALSx continued to have Autocenter issue (fix w/ FORCE button).  ALSy also would look bad after locklosses, but something happens with Full & Manual Alignment that stabilizes it for locking (mostly).  If there is still an issue, holding at LOCKING ARMS GREEN and waiting for ALS WFS to settle before moving on seemed to help.

Microseism continues to fall over the last 16hrs.

LOG:

• 1555--1619 technical cleaning in optics lab (kim)
  • 1849-1905 h2room swiffering (kim)
• 1606 Lockloss!  (right before the 1630 Commissioning time!!  For commissioning, switched gears since H1 was down to first heat OM2.
  • Initial locking attempts had ALS issues.  ALSx had issue seen yesterday where the Autocenter (WFS) was not working for ALSx, but ALS_XARM thought WFS were all offloaded.  For ALSy, the arm power just did not look stable (symptom:  arm power hovered around 1.0 but then would got into an waivering state with the power and then lose lock after a few seconds).
  • Ran Initial Alignment
    • BUT ALSx still has the Autocenter issue....so while green arms were aligning I clicked a FORCE button and WFS were engaged.  Then rest of alignment was fine.
  • Started locking....I believe this time ALSx autocenter was ok all on its own!  Also made it to NLN (1740utc) with no issues!
• 1630 Commissioning time starts:  OM2 heating was first (started around 1720); DARM offset meas with "hot" OM2; SEI test for ETMx by Jim...
• 1836-1846 CER and then to LVEA, treading lightly, to check cables (daniel)
• 1857 Dust Mon 6 (300nm) in LVEA alarm---jumped up to 34k & then 55k within 10min.
  • 1906-1912 RyanC walking out to East Bay to investigate/sniff around while treading lightly.  He did not smell anything, but did confirm seeing the large counts on the dust monitor
• 1945 LOCKLOSS
  • ALSy looked bad, so ran a manual alignment for green arms (1955-2004)
  • But still had issues with LOCKING ALS locklosses, so held at LOCKING ARMS GREEN while watching ALS WFS channels until they calmed down and then continued on past LOCKING ALS
  • DRMI initially looked ok, but not great, so eventually ran CHECK MICH FRINGES and PRMI to lock up DRMI.
• 1952-2036 Matt running down Yarm
• 2030-2122 Ibrahim Y-arm walk
• 2051-2217 CEBEX walkthru at MY (janos)
• 2101 Opening OSB Receiving Roll-Up Door (christina)
• 2158 Back to OBSERVING (post-commissioning)

TITLE: 01/31 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 157Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.28 μm/s
QUICK SUMMARY:

Observing at 156Mpc and have been Locked for over 3 hours. Secondary microseism is coming down and wind is low.

I turned on the filters for the esd etmx glitches, while we were relocking. These filters multiply to 1 so shouldn't cause any issues, the turn on didn't affect the ALS lock at the time. I have accepted the changes in the safe sdf. Still need to figure out the limit to try to ride out the glitches, so there is no effective change to the IFO at the moment. SDF changes will need to be accepted in OBSERVE, when we get there.

Thu Jan 30 10:07:13 2025 INFO: Fill completed in 7min 10secs

Gerardo confirmed a good fill curbside. TCmins [-61C, -59C] OAT (-1C, 30F) DeltaTempTime 10:07:13

Similar to a few times yesterday, the X-arm's ALS_XARM guardian thought it was good with WFS OFFLOADED, but X-Arm's Auto Center is RED w/ no inputs to the WFS filter banks (similar to what I saw in June (alog 78326). 

I'm attaching screenshot which shows a little bit of everything with ALSx: 

• X-arm locked with a low power below 1.0 (it's usually up at 1.3)  BUT it has no WFS signals---they're all zero on ndscope....eventhough it is at ETM TMS WFS OFFLOADED.
• ALS Overview with RED Auto Center
• Also have the Trigger Window

Back in June, I clicked the FORCE button on the Trigger Window and this would bring Autocentering back.  (Right now I'm running an Initial Alignment and the Autocenter was still OFF....so I did another FORCE).

H1 just lost lock before Commissioning Time (1422288412).

TITLE: 01/30 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 157Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.39 μm/s
QUICK SUMMARY:

H1's been locked 8.5+hrs.  The microseism which rose close to the 95th percentile in the last 24hrs looks like it's slowly decreasing over the last 6hrs (peaks still hitting the 95th.

On today's docket is a long Commissioning Down Time starting with Calibration in an hour at 1630utc/830amPT and a scheduled end at 2200utc/2pmPT.

TITLE: 01/30 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Earthquake
INCOMING OPERATOR: TJ
SHIFT SUMMARY: Currently relocking and at PREP_DC_READOUT_TRANSITION. Lockloss was due to a nearby earthquake, but luckily we didn't have to wait in DOWN for very long before we could start trying to relock.
LOG:

00:00 Relocking and at DHARD_WFS
00:27 NOMINAL_LOW_NOISE
00:30 Observing

04:55 Lockloss due to earthquake
    05:05 Started trying to relock, ran an initial alignment
 

Lockloss @ 01/30 04:55 UTC due to a nearby earthquake from Alaska. Holding in DOWN until the earth stops moving.

Here're the bare-bones instructions to run the DARM loop critique -- an automated set of plots that were inspired by the presentations given over the years that compare the transfer functions of the DARM loop between the two sites, e.g. G1501372, G1700316, G2000149.

(0) Conda activate the latest pydarm environment.
    ~$ conda activate /ligo/groups/cal/conda/pydarm
This is a symbolic link to the latest tagged version of pydarm.
    () ~$ which pydarm
        /ligo/groups/cal/conda/pydarm/bin/pydarm
    () ~$ pydarm --version
        20240821.0
    () ~$ ipython
    In [1]: import pydarm
    In [2]: pydarm.__version__
    Out [2]: '20240821.0' 
Note the version of pydarm is the same on the command line and within the ipython session *because* we activated the correct pydarm conda environment. The command line pydarm internally activates this environment automatically, but any old ipython session may not have the right version of pydarm if you just import "from scratch" without making sure you're in the right environment first. So -- any time you're running script or python session pyDARM these days -- make sure that you've activated the conda environment.

Is this the right version? check https://git.ligo.org/Calibration/pydarm/-/tags see if that version is the latest, i.e. the top of the list.

It is. And this will *always* be true, by process of deploying the latest tag (see deploy script).
To compare previous versions of tags, go to https://git.ligo.org/Calibration/pydarm/-/compare?from=master&to=master and change the drop-down menu to compare one tag to the other.
If you want to activate an environment with an older version of pydarm, then head to the folder /ligo/groups/cal/conda/ and activate the environment you like.


(1) Grab the DARM loop model parameter sets that you want to plot and/or compare. If at LHO, wanting H1 parameter files, then (back out on the command line, not in yet in a python session)
Find the list of reports and tags:
   () ~$ pydarm ls -r
From that list, find the model parameters installed in the front-end:
   () ~$ pydarm ls -r | exported

Once you find what you like, go into that report directory, e.g.
   () ~$ cd /ligo/groups/cal/H1/reports/20240927T211612Z
Look for pydarm_H1.ini, and copy it somewhere you like, or at least store where it lives.

If you're at LHO, want L1 parameter files, then the easiest thing is to download it from the web. Head to the https://ldas-jobs.ligo-la.caltech.edu/~cal/ and scroll down to the list of all reports, and find the entry that's been exported most recently e.g. 20240408T200652Z, and download the pydarm_L1.ini and save it to a known location.

(2) Start critiquing:
~$ ipython
In [1]: from pydarm.darm import DARMModel

In [2]: d = DARMModel('/ligo/groups/cal/H1/reports/20240927T211612Z/pydarm_H1.ini')

# Plot a single parameter file's model:
In [3]: d.plot(filename='/ligo/home/jeffrey.kissel/2025-01-21/20240927T211612Z_pydarm_H1_critique.pdf',label=['H1'])

# Compare against another, say, previous version of the model
d_prenewdarm = DARMModel('/ligo/groups/cal/H1/reports/20231027T203619Z/pydarm_H1.ini')

from pydarm.plot import critique

critique(d,d_prenewdarm,filename='/ligo/home/jeffrey.kissel/2025-01-21/20240927T211612Z_vs_20231027T203619Z_pydarm_H1_critique.pdf',label=['H1 20240927T211612Z', 'H1 20231027T203619Z'])

# Compare two IFOs:
In [9]: d_H1 = DARMModel('/ligo/groups/cal/H1/reports/20240927T211612Z/pydarm_H1.ini')

In [10]: d_L1 = DARMModel('/ligo/home/jeffrey.kissel/2025-01-21/20240408T200652Z_pydarm_L1.ini')

critique(d_H1,d_L1,filename='/ligo/home/jeffrey.kissel/2025-01-21/20240927T211612Z_H1_vs_20240408T200652Z_L1_critique.pdf',label=['H1 20240927T211612Z','L1 20240408T200652Z'])

# Compare one IFO's parameters, while updating one of the parameters on the fly
In [9]: d_H1 = DARMModel('/ligo/groups/cal/H1/reports/20240927T211612Z/pydarm_H1.ini')
In [10]: d_H1_moreAA = DARMModel('/ligo/groups/cal/H1/reports/20240927T211612Z/pydarm_H1.ini') #Intentionally the same
# Update the parameter you want,
In [6]: d_H1_moreAA.sensing.omc_filter_noncompensating_modules
Out[6]: [[9, 10], [9, 10]]

In [7]: d_H1_moreAA.sensing.omc_filter_noncompensating_modules = [[9,10,10],[9,10,10]]

In [8]: critique(d_H1,d_H1_moreAA,filename='/ligo/home/jeffrey.kissel/2025-01-21/20240927T211612Z_H1_vs_20240927T211612Z_H1_2x16kDigitalAA_critique.pdf',label=['Nominal','1x More 16k AA'])