TITLE: 03/19 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 143Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY:The low range coherence check yielded, CHARD_Y and PRCL at low frequency. The range has been in the mid 140s, we've been locked for 5.5 hours.

02:06 low frequency glitch, EX and DCPD saturation

LOG:                                                                                                                          

FranciscoL, RickS

On Tuesday, March 18, we moved the PCALX lower beam by r = 2.5mm, \theta = +237 deg from its nominal center. We expect to see a change of 20 HOPs in \chi_XY -- returning to the value it was a week ago.

Placed target in the same alignemnt as in the previous actuation (TARGET_ON). Both individual beam voltage values, as found, were very similar to the values recorded at the end of the move done last week. We actuated by turning counterclockwise on the pitch adjuster of the outer beam folding mirror, with minor adjustments in yaw. The voltage of the lower beam after the move was higher than last week, it could be from AoI of the optics, but documenting here for future reference.

The following table shows the voltage values as read by the Keithley voltmeter we use during the procedure

We have one more actuationg left in which we move the beam back to nominal center. For the upcoming move, we expect \chi_XY to stay the same.

FranciscoL, RickS, SivanandaR

In summary:

On Tuesday, March 11, we moved PCALX lower (outer) beam by r = + 2.5 mm, \theta = - 33 deg (from horizontal) on the ETM. We expect to see a large (~20 HOPs) change in \chi_XY.

From our investigations -- an independent method to estimate IFO beam offset using the Pcal -- we believe that the IFO beam offset, when facing the ETM, is (+ 14.3 mm, -- 09.3 mm) in cartesian coordinates. These coordinates yield an angle of arctan(-- 9.3/14.3) ~ -- 33 deg from the horizontal axis of the ETM center.

The first pdf file (polar_out.pdf) plots the IFO beam offset. The black points represent the measurements of a2l (located at '/opt/rtcds/userapps/trunk/isc/common/scripts/decoup/BeamPosition/a2l_lookup.m'). The green points are what is inferred by Pcal measurements. For the Pcal to estimate the IFO beam offset, we use the scalar product of \vec(c) -- the displacement vector of the Pcal center of force for a given actuation, and \vec(b) -- the IFO center of force, as it is derived in T2400032 equation 11. From the plot, there is a clear disagreement on the horizontal component of the IFO beam from both methods. Following equation 11, a measurement in which an actuation from the Pcal beams results in a parallel displecement of the pcal center of force to the real IFO beam center of force should maximize the change \chi_XY. Conversely, an actuation that is perpendicular would not be seen by \chy_XY (no change). The actuation for today was parallel to what the Pcal estimates is the IFO beam position. We plan to make a second actuation, in which we move perpendicular to our estimate of the IFO beam. Ideally, these measurements would increase our confidence of the IFO offset.

We aligned the target by setting an angle gauge at the calculated 33 deg as seen in the first image (TARGET_ON).

We aligned the Pcal beams to the corresponding apertures by (1) blocking one beam and (2) aligned beam of interest by maximizing the Rx sensor voltage readout from a Keithley digital multimeter (KVM). Since the upper beam has shown inconsistencies in the horizontal displacement (83051), we are actuating on the lower beam. The second image (BOTH_BEAMS) shows both beams after moving the lower beam.

The following table lists the voltage value at each relevant step of the process:

Some observations from today's visit to ENDX:

• Clockwise rotation on the yaw actuator moved the lower beam up on the Rx sensor.
• Clockwise rotation on the pitch actuator moved the lower beam to the right on the Rx sensor.
• Noticed an increase in upper (inner) beam after optimizing on center aperture -- so the beams may drift in the order of less than 1 mm on the Rx (roughly half on the ETM) during the span of a week.
• Power imbalance of ~7% of both beams on the center aperture when the target was on.

This is the first of three actuations. Additionally, the data processing still needs about a week of data to diagnose results. We will have nominal results in ~3 weeks.

J. Freed

Today I collected 2 phase noises, first phase noise is of the 80 MHz OCXO after it has gone through an RF distributer. The reference was the SRS SG382 at 80MHz

The second is of the Double Mixer again but with an extra focus on the 8192Hz sideband.The reference was agian the SRS SG382 at 80MHz-4096Hz

These tests was done with the direct plug in method without using a PLL. This requires both the device under test and the reference device to be at quadrature. Normally a PLL is required to keep them there, however since both devices are connected to the LIGO timing system in some way,  a PLL is unnecessary to keep them locked in quadrature. To put them in quadrature I just lined them up on an oscilloscope best I could then added 90 deg by adjusting the phase on the SRS.  I bypassed the internal amp of the BluePhase1000 for all tests.

DM_vs_RF.pdf Is a plot of the two phase noises, as seen, the low frequency noise (<2Hz) has these humps. I now attribute these to the RF distributer causeing a shape change in the pure sin wave signal. 

RF_Distributer_Signal.jpg Shows how the RF distributer has a not exact sin wave (Yellow) compared to the SRS Pure tone (Blue)

DM8kSideband.pdf Shows a close up on the 8k sideband that will also couple into our SPI output 

TITLE: 03/18 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Preventive Maintenance
INCOMING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 10mph Gusts, 6mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.22 μm/s
SHIFT SUMMARY:
H1 has almost recovered from Maintenance day changes, We are currently in Nominal_Low_Noise but not Observing as the Cameras need to be reverted back to the old server.
NLN reached at 23:27 UTC.

Sheilas CPy measurements were completed.
 

LOG:

TITLE: 03/18 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Preventive Maintenance
OUTGOING OPERATOR: Tony
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 7mph Gusts, 4mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.22 μm/s
QUICK SUMMARY:

• We're sitting in LASER_NOISE_SUPPRESSION working on the cameras
  • The relock was automated after an initial alignment

FYI - I've added a new block to the SUS SVN at SUS/common/models/

Adding         SIXOSEM_T_ESTIM_STAGE_MASTER.mdl   - this is simulink R2019a
Adding         SIXOSEM_T_ESTIM_STAGE_MASTER_tmp.mdl  - this was my working file in R2023b
Committed revision 31074.

These are a long way from done. This will be the new piece for the OSEM Estimator part for the HLTS (PR3)

The ECR is https://services1.ligo-la.caltech.edu/FRS/show_bug.cgi?id=32526

Robert, Betsy, Sheila

We went to the ITMY optical lever piers to check the CPY alignment, similar to 77557.  We tried to reset the optical lever back to where it was before we started, the optical lever is now slightly shifted though.  The sum dropped from 9060 coutns to 8930 counts, PIT went from -12.7 urad to -19.7 urad and YAW went from 1.3 urad to -4.4 urad.

WP 12393
ECR E2200105
DCC D2200162
DCC D1002872
T2300221

Started installation of the SEI HAM1 ISI field cables. Cables are now pulled from the CER SEI-C1 rack to the LVEA near HAM2/SUS-R1. Final routing of cables will continue next week. Documents D2200162, D1002872, and T2300221 don’t have the same flange layout. Imagine they will get updated once plans are finalized. Cables will be routed to HAM1 flanges as listed below:

Corner 1: Flange D1
SEI_HAM_15
SEI_HAM_16
SEI_HAM_17
SEI_HAM_18

Corner 2: Flange D5
SEI_HAM_33
SEI_HAM_34
SEI_HAM_35
SEI_HAM_36

Corner 3: Flange D3
SEI_HAM_51
SEI_HAM_52
SEI_HAM_53
SEI_HAM_54

CPS 1&2: Flange D5
SEI_HAM_63
SEI_HAM_64

CPS 3: Flange D3
SEI_HAM_65
SEI_HAM_66

F. Clara, M. Pirello

I took two single bounce OMC scans today with the help of TJ and Tony. Here are some notes to future me and others to reference if we want to do single bounce scans:

• align one ITM. We chose ITMY today because of work happening with the oplev that required ITMY to be aligned
• for this scan, I increased the input power to 10 W
• first check if the fast shutter is OPEN (silly mistake, spent a few minutes wondering where the beam was)
• take the OMC guardian to DOWN. After the fast shutter mistake, TJ and I were fighting to scan and realized that the guardian was set to "OFF_RESONANCE" and overriding us as we scanned
• I turned on the AS centering loops by hand, DC3 and DC4 P/Y (this aligns OM1 and 2 onto the AS WFS)
• To ensure alignment to AS_C was good, TJ and I ran SR2_ALIGN in the ALIGN_IFO guardian (after this I had to reengage the DC centering loops because the ALIGN_IFO guardian turned them off going to DOWN)
• I saw an off-centered beam on the OMC QPDs, so I engaged the OMC ASC master gain which centered the QPDs
• There was a moment where I thought the PZT2 offset mattered, so I changed it. I see now that it probably didn't matter, and only effects where the scan starts
• I used an OMC scan template in [userapps] omc/h1/templates/OMC_scan_single_bounce.xml
• run some scans! Today, I ran a scan with nominal settings, and another scan with the RF9 modulation down by 3 dBm and the RF45 modulation down by 6 dBm, which are the settings in full lock
• my scans are saved in [userapps] omc/h1/templates/OMC_scan_single_bounce_RF_cal.xml

Edit to add: unfortunately the scan results from today look pretty bad. In short, the peaks look "lopsided" somehow, and so I'm not sure the results are usable. Looking back at Jennie W's previous scans, it looks like she had to slow them down to 200 second scans. I only did a 100 second scan with amplitude 105 so maybe I scanned too fast. I'm not sure what the correct resolution of this is, because the scans I did in 2022 were 100 second scans and the results were fine. Adding this note here for reference in the future to think about the appropriate scan length and amplitude.

TITLE: 03/18 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Preventive Maintenance
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 7mph Gusts, 4mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.24 μm/s
QUICK SUMMARY:

Be careful using the Roll up down between the receiving area and LVEA. It seems to be  in need of maintenance.
SNEWS Test T565015 16:00:15 UTC
HAM7 ISI WD Tripp17:09 UTC
HAM7 CPS Glitch 17:10 UTC
2 Norco trucks went in the Y armdirection from the parking lot.

Mechanical room has fumes in it , doors  have been opened to allow ventilation while Roger Bros

HAM7 CPS glitches 18:03 UTC

Dust alarms have been telling us there is dust.
 

Expected work:
LVEA:
Ham1 Laser Barrier taken down?
Lighting Fixtures above HAM1
Fil HAM1 pulling cables.
Vac roughing pumps & compressor
OMC scans by Elenna

EX:
PCAL ES Beam Mv over by 9am
Laser hazard Camilila & TJ TMS & ALS Return beam
Rahuls OPLEV SUS Charge measurements

EY:
Rahuls OPLEV SUS Charge measurements
Vac EY comp still in progress

CDS:
Dan LDAS maint.
Eric BS camera server testing

Still on going:
ITMY CPy adjustments.

M. Todd, C. Compton, T.J. Shaffer

We went down to EX with the intention of getting the reflected ALS beam to be a little cleaner, as we've been plagued with this lobey beam seen in alog 82752. If we were to succeed in cleaning up the beam we would have taken beam profile measurements; however, we were unable to make the beam any clearner, and any profile measurements did not make sense.

We started off a little cleaner than the previous log (82752) but we still had some weaker lobes that looked like ears (lending a sort-of Mickey Mouse shape).

Measuring the ALS return beam at  ETMX, we misaligned ITMX and ITMY. Starting slider values were:

Moved to ETM Y: -2.4, TMSX: 634.8. (seems too big check this number on ndscope??), got worse, now has almost two lobes
Other way in Tat: ETM Y: -346.4, TMSX: -275.2. looks better, similar to original: Mickey Mouse.
Yaw back, not in Pitch: ETM P :204.4, TSMX P 139.0, now worse in Pit than yaw

LVEA has been swept

Plot attached, reset at 19:30UTC.

There has been activity near that TCS rack this AM, both cable pulling and wire racks moved nearby. We've seen this happen before, LLO is currently trying to investigate why. 

Tue Mar 18 10:12:51 2025 INFO: Fill completed in 12min 47secs

h1caley's OBSERVE.snap is now a sym link to its safe file, bringing it in line with h1calex and the LLO models. h1caley_safe.snap was modified to monitor all of its channels.

lrwxrwxrwx 1 controls   advligorts     62 Mar 18 11:01 h1caley/h1caleyepics/burt/OBSERVE.snap -> /opt/rtcds/userapps/release/cal/h1/burtfiles/h1caley_safe.snap
lrwxrwxrwx 1 controls   advligorts     62 Apr 21  2015 h1caley/h1caleyepics/burt/safe.snap -> /opt/rtcds/userapps/release/cal/h1/burtfiles/h1caley_safe.snap

lrwxrwxrwx 1 controls   advligorts     62 Apr 28  2017 h1calex/h1calexepics/burt/OBSERVE.snap -> /opt/rtcds/userapps/release/cal/h1/burtfiles/h1calex_safe.snap
lrwxrwxrwx 1 controls   advligorts     62 Apr 21  2015 h1calex/h1calexepics/burt/safe.snap -> /opt/rtcds/userapps/release/cal/h1/burtfiles/h1calex_safe.snap

We lost lock from the calibration, so we tried to lock ALS without the linearization (some background in this alog: 83278.)  An active measurement of the transfer function from DRIVEALIGN_L to MASTER out was 1 without the linearization, and -0.757 with the linearization on.  So I've changed the DRIVEALIGN gain to -1.3 in the ALS_DIFF guardian when the use_ESD_linearization is set to false.  

We tried this once, and it stayed locked for a DARM gain of 400, but unlocked as the UIM boosts were turning on. We tried this again but it also didn't lock DIFF, so it is now out of the guardian again.

I looked at a few more of the past ALS DIFF locks, both sucsesful and unsucsesful attempts we are saturating the ESD (either the DAC or the limiter in the linearization) in the first steps of locking DIFF.  We do these steps quite slowly, stepping the darm gain to 40 waiting for the DARM1 ramp time, stepping it to 400, then waiting twice the ramp time, then engaging the boosts for offloading to L1.  I reduced the ramp time from 5 seconds to 2 seconds to make this go faster.  This worked on the first locking attempt, but that could be a coincidence. 

We will leave this in for a while, so that we can compare how frequently we loose lock at LOCKING_ALS.  In the last 7 days we've had 48 LOCKING_ALS locklosses, and 19 locklosses from NLN, so roughly 2.5 ALS locklosses per lock stretch. 

We removed the BSC1 temperature sensor to run some testing in the lab.  Will reinstall next week.