1610 - 1700 hrs local -> To and from Y-mid + Y-end

Today took nearly 25 minutes to over-fill CP3.  It is as if the pump is really low.  Like this past Sunday's fill the ambient temperature is unseasonably warm.  Also, the BT cleaning crew have been leaving the Y1 BTE doors propped open overnight.  Could the extra warm BT be significantly changing CP3's consumption (see Mike Z.'s comments from Sunday's entry)?  Also, there has been a slight uptick in Y-arm pressure for the past day or so.  I confirmed that IP9 is programmed in FIXED voltage @ 7000V and isn't stepping between voltages.  

Next scheduled over-fill to be Thursday, Feb. 18th before 4:00pm

J. Kissel, R. Schofield
WP 5733

Robert and I moved around cabling for the recently re-installed GND STS that has been buried +X (at ~10 m away from the building) of the ETMY building. This STS (S/N 89921) was formerly in the vault during O1. Now cabling for this STS is such that the BNCs, from the hostbox outside, go into channels 13, 14, 15 of the PEM BNC AA chassis at the very bottom of the TCS-C1 rack. Out of the back of this chassis, we've installed a new (standard L-Comm) DB9 cable which now goes to the front of the HEPI AA chassis, in U30 of the SEI-C1, in the port marked "27-30." This corresponds to the channels ADC3_[26-28], which have been pre-wired up to go into STS_A at the top level of the EY model. In addition, I've unhooked the top-level GND_STS block from the library, and added three new sets of channels,
H1:ISI-GND_STS_EYBURIED_X
H1:ISI-GND_STS_EYBURIED_Y
H1:ISI-GND_STS_EYBURIED_Z.
Each above channel prefix set has 
- test points stored to frames as "_DQ" (stored at 256 [Hz]), e.g. "H1:ISI-GND_STS_EYBURIED_Y_DQ";
- an EPICs "_MON" channel, e.g. "H1:ISI-GND_STS_EYBURIED_Y_MON";
- the full BLRMS infrastructure with EPICs channels "_BLRMS" with associated BLRMS extensions for the given band, e.g. "H1:ISI-GND_STS_EYBURIED_Y_BLRMS_30M_100M."
The modified top-level model has been committed to the userapps repo.

Because the buried STS readout system has two factors-ot-two differences between the nominal STS readout system (one factor from the fact that only the positive legs of the host box signals are carried in via BNC, and then the other is from reading out this single-ended, half-signal with a differential ADC), I had to create new calibration filters (in FM2 of the H1:ISI-ETMY_ST1_GNDSTSINF_A filter banks, called "Cal_Buried") which multiply the nominal gain (10.1725 [(nm/s) / ct]) by 4 to get the calibration right. Thus, all of the derivatives of the above mentioned channels are calibrated into (nm/s), as is the case for all other GND_STSs.
The modified filter file has been loaded, committed to the repo, and the new FMs have been turned on.

As of Feb 17 2016 at 00:00 UTC, these channels are calibrated and awesome.

Calibrated DTT Template saved as
/ligo/home/jeffrey.kissel/2016-02-16/2016-02-16_H1ISIETMY_GND_STS.xml

P.S. Robert suspects that the best position for the STS is roughly at ~20 [m] from the building because it balances high-frequency drop off of coherence and coupling to building tilt. I.e. 10 [m] is a little too close, so the building tilt pollutes the ~40 [mHz] signal just as much as the STS on the slab, where as at 40 [m], the ~0.5 [Hz] motion is no longer coherent enough to do viable subtraction. So, he may dig one more hole and move it to 20 m, but it'll likely stay put until the next time Robert's in town.

Jeff, Darkhand, Kiwamu,

We have been meaning to do this, but kept missing a chance to do. Today we have fliiped the sign of the ESD bias voltage both on ETMX and ETMY.

This alog only describes what we did on the digital front end models. We will perform a set of confirmation measurement and verify the H1 DARM model later.

See alog 22135 for a concise summary of the bias flip.

[Bias flip on ETMY ]

• We flipped the bias request voltage from +9.5 => -9.5 in SUS-ETMY_L3_LOCK_INBIAS
• No other change required in SUS-ETMY because there is a if statement in ISC_LOCK which automatically checks the change in the bias sign and compensate for it by changing the sign of L3_DRIVEALIGN_L2L_GAIN.
• In CAL-CS, we have changed DARM_FE_ETMY_L3_DRIVEALIGN_L2L_GAIN from +30 to -30.
• Similarly, we have changed DARM_ANALOG_ETMY_L3_GAIN from -1 to + 1.

[Bias flip on ETMX]

• We flipped the bias request voltage from -9.5 to +9.5.
• We flipped DRIVEALIGN ellements as follows.
  • SUS-ETMX_L3_DRIVEALIGN_L2L_GAIN, from +1 to -1
  • SUS-ETMX_L3_DRIVEALIGN_L2P_GAIN from +0.021 to -0.021
  • SUS-ETMX_L3_DRIVEALIGN_L2Y_GAIN from 0.007 to - 0.007
• We changed the force coefficient of the linearization from -124518.4 to + 124518.4 in SUS-ETMX_L3_ESDOUTF_LIN_FORCE_COEFF
• All the the above changes are now written in ISC_LOCK with a if statement, so that it automatically checks the bias sign and apply a proper set of parameters.
• We have not updated CAL-CS for ETMX because it is currently not in use.

I've added a block to the TCS model to estimate the real-time thermal lenses in each of the test masses and the surface curvature of each of the test masses.

OPTIC_LENS.mdl

The main new library block, shown in the attached figure, is OPTIC_LENS which takes as inputs:

• Ring heater power
• CO2 laser power (N/A for ETMs)
• IFO ARM power (calculated from H1:ASC-TR_X_B_SUM_OUTPUT and H1:ASC-YTR_X_B_SUM_OUTPUT)
• Also, the estimated surface absorption of the optic

Each of these inputs goes into a filter that contains (or will contain) the transfer function for power to diopters for that specific actuation. These are:

• H1:TCS-ITMX_SIM_SUB_DEFOCUS_RH   (single-pass substrate thermal lens from the ring heater)
• H1:TCS-ITMX_SIM_SUB_DEFOCUS_CO2  (single-pass substrate thermal lens from the CO2 laser)
• H1:TCS-ITMX_SIM_SUB_DEFOCUS_SELF (single-pass substrate thermal lens from self heating)
• H1:TCS-ITMX_SIM_SUB_DEFOCUS_STATIC (single-pass substrate static lens from construction)
• H1:TCS-ITMX_SIM_SURF_DEFOCUS_RH (single-pass surface lens from RH: inverse of the ROC change from the RH)
• H1:TCS-ITMX_SIM_SURF_DEFOCUS_SELF (single-pass surface lens from self heating: inverse of the ROC change from self heating)
• H1:TCS-ITMX_SIM_SURF_ROC_NOM (nominal ROC of the optic)

which are summed together to yield. These are outputs for the model:

• H1:TCS-ITMX_SIM_SUB_DEFOCUS_FULL_SINGLE_PASS: the total single pass thermal lens in diopters
• H1:TCS-ITMX_SIM_SURF_DEFOCUS_FULL (the inverse of the current ROC, including thermal effects)
• H1:TCS-ITMX_SIM_SURF_ROC_FULL (the current ROC, including thermal effects)

h1tcscs.mdl

There are four of these blocks in the main TCS model h1tcscs.mdl - one for each test mass. Although the ETMs contain inputs for CO2 lasers, these are grounded. See the attached figure.

The outputs from the four blocks are currently terminated. I plan on updating the model to create channels for COMMON and DIFFERENTIAL MICHELSON and ARM lenses and others, as required. This will be after I've verified that the model and filters are all working correctly.

• Title: 2/16 OWL Shift: 16:00-00:00UTC (08:00-16:00PDT), all times posted in UTC
  

• State of H1: Locking
  

• Shift Summary: Typical maintenance day

• Incoming Operator: Corey

• Activity Log:

• 15:15 Chris S to EX for beam tube sealing
• 16:03 John to LVEA to Join Bubba
• 16:15 John soft closing GV5&7 to crane genie lift over beam tube
• 16:27 Ryan B restarting alog
• 16:34 Christina/Karen to EY to clean
• 16:51 GVs opening
• 17:01 SNEWS test in
• 17:03 Fil to LVEA to check inventory
• 17:24 Coca-Cola truck on site
• 17:40 Norco truck on site
• 17:40 Hugh, Robert to LVEA
• 17:54 Christina, Karen to LVEA to clean
• 18:12 Fil to EX to install chasis
• 18:46 Hugh to ends for Hepi fluid level check
• 19:08 Fil to EY to install chasis
• 19:12 Kyle to MY
• 19:27 Hugh back
• 19:31 Kyle to EX
• 19:40 Fil back
• 20:23 Kyle back
• 21:56 Hguh moving seismometer into LVEA
• 23:03 Corey resetting PSL WD
• 23:31 Corey into optics lab
• 23:56 Kyle to MY to overfill CP3

At 23:03UTC (3:03pmPST) I reset the PSL Watchdog this afternoon & CLOSED FAMIS Request #3585.

13:55 PST h1tcscs restarted

14:28 PST h1isietmy restarted

14:28 PST DAQ restarted

DAQ restart captures above model changes plus addition of all vacuum controls channels.

The h1boot-backup computer crashed with a kernel panic sometime Friday afternoon (Feb. 12), rebooted using the reset button.

This was moved last week.

Attached are some ASDs and coherence plots.  The reference traces are from a time of 20 to 30 miles winds this morning and the current traces are from an early time in the weekend when things were much quieter.

The Y axis looks good with strong coherence and similar spectra responding to the wind-tilt as expected.  The X axis similarities are okay but not as strong as Y's.  We don't understand the Z axis as the HAM5 unit does not respond to the wind like the ITMY seismometer and the coherence is bad compared to the X and especially the Y.

Aidan is making changes to h1tcscs which requires reading EPICS channels from the Beckhoff system. Here is the current number of H1 models which use CA to read/write data to external systems.

* The mid station IOP models lack a full timing system (no IRIGB signal) and instead get their GPS time from the DAQ via Channel Access.

The list of EZ_CA_[READ/WRITE] channels was obtained by:

cd /opt/rtcds/lho/h1/release/src/epics/fmseq

ls|grep -v "_daq"|xargs grep "EZ_CA_READ"

ls|grep -v "_daq"|xargs grep "EZ_CA_WRITE"

Set the phase using the in-lock stretch from some days ago. We can in principle just change the DC3 and DC4 input matrix and start RF-centering.

I have turned off two heaters in the LVEA. HC4 and HC5 were both set to 4ma control at 18:50 utc.

Bubba and I were able to crane the Genie manlift over the Y beam manifold this morning in order to continue the crane rail work.

GV5 and GV7 were soft closed for the duration from UTC 16:15 to 16:53.

The crane behaved normally.

Are complete. I will post plots when I get a chance.

Laser Status:
SysStat is good
Front End power is 32.63W (should be around 30 W)
Frontend Watch is GREEN
HPO Watch is RED

PMC:
It has been locked 11.0 days, 23.0 hr 23.0 minutes (should be days/weeks)
Reflected power is 3.203Watts and PowerSum = 25.7Watts.

FSS:
It has been locked for 0.0 days 12.0 h and 23.0 min (should be days/weeks)
TPD[V] = 1.415V (min 0.9V)

ISS:
The diffracted power is around 8.004% (should be 5-9%)
Last saturation event was 0.0 days 12.0 hours and 23.0 minutes ago (should be days/weeks)
 

12 Counts on HAM5

In the first attachment you can see that something happened to the TMS osems on Jan 21st that makes the peak to peak noise increse by more than a factor of 10. This is still the case. 

I then took a look at the osem spectra, (the fast channels which are not DQ) and saw a 16 Hz comb in RT and SD (second screenshot).  Without saving I re ran the measurement including TMSY channels for comparison, and then saw that the comb appeared to have gone away.  Spectra of the 256 Hz DQ channels from the time when I originally saw the 16Hz comb are in the third attachment, there is no comb here. 

The last attached screenshot shows the osem spectra for both TMSs that I am measureing now, there is some oscillation around 1800 Hz.  This is very similar to the behavoir reported in 25062  and 20078

{Rana, Evan}

This evening we looked at the coupling of DCPD bias voltage into DARM.

Each DCPD is biased with +12 V from a linear regulator with a 1 Ω output resistor. We wanted to inject extra bias noise, so we exposed the bias lines with a breakout board at the DCPD chassy in the HAM6 rack (see D1300502). Then we summed in the output of an SR785 across an impedance of 10 kΩ in series with 20 µF (see diagram; green shows the normal DCPD electronics and red shows the addition). The 10 kΩ gives a 1:10⁴ ratio of bias fluctuation to drive voltage, and the capacitor ac-couples the drive so that it does not pull on the bias at dc.

With the SR875 we drove a 1 Vpk line first at 187.3 Hz and then at 62.4 Hz (i.e., the bias fluctuation was 70 µV rms). We looked at the response in DARM (at 2 W dc readout, with DARM still controlled by EX). We had 10 mA dc on each PD, in the 400 Ω transimpedance configuration.

For 187.3 Hz (from 02:03:00 to 05:22:00 Z), the magnitude in DARM was 1.13×10⁻¹⁸ m rms, which implies a coupling of 1.6×10⁻¹⁴ m/V. The noise of the regulator at this frequency was 0.9 µV/Hz^1/2, which implies a DARM noise of 1.4×10⁻²⁰ m/Hz^1/2.

For 62.4 Hz (from 05:33:00 to 05:56:30 Z), the magnitude in DARM was 1.4×10⁻¹⁸ m rms, which implies a coupling of 2.0×10⁻¹⁴ m/V. The noise of the regulator at this frequency was 1.9 µV/Hz^1/2, which implies a DARM noise of 3.7×10⁻²⁰ m/Hz^1/2. Note that there is some room for error here because the DARM control configuration here is not exactly the same as the low-noise configuration. However, the ugf and phase margin should not be too different in the two configurations.

This is very close to the current low-noise DARM noise floor. However, if DARM is limited by voltage noise of the regulators, we should either expect that the DCPD null stream is equal in magnitude to the DCPD sum (it isn't), or the regulator noises are coherent (they aren't).