This morning I put in upgrades for both guardian core (r1076) and cdsutils (r322).  All guardian nodes have been restarted (except for ITMX SUS and SEI which are under test by Jim W.  Will restart as soon as he's done).

cdsutils r322 new improvements/features:

• add "gpstime" module for handling GPS times
• fixes/improvements to "audio" command (i.e. "rockifo")
• new "water" command for waterfall plotting
• new "step" command, and guardian-friendly Step class
• minor performance improvements to Ezca and LIGOFilter
• improve test suite
• improved documentation

guardian r1076 improvements/features (see also LLO aLOG 13930):

• support user-assigned state indices
• add node NOMINAL state, which represent the intended state during full operation
• add node OK status bit, which is True if the node is running, in it's NOMINAL state, not in error, etc.
• improved test suite
• improved documentation

Here's the updated guardian control screen that comes with this upgrade:

Note the new "NOMINAL" state field.  The NOMINAL state is NONE by default if not set in the code module (which is the case here for SUS_BS).  The orange background reflects the fact that the new OK bit is False, which in this case is because there is no NOMINAL state set.

Also note the number fields to the right of the state names, which show the numeric index for the current states.  Now that we manually set these numbers, they have a bit more meaning, which is why it's useful to display them.

We now need to go through all systems and add appropriate state indices and nominal state definitions.  This was done already at LLO, so I'll be adopting the same standards.

In the event of a power loss during a science run, the APC Smart-UPS (Model: 1500, Max Configurable Power: 980 Watts/1440 VA, Mfg. Part: SUA1500R2X122) will continue powering the Pre-Stabilized Laser (PSL) to prevent laser damage. The UPS (Uninterruptible Power Supply) draws for its transformer a large amount of current, so we measured the device's magnetic field at various distances to determine the 'minimum distance' --  how close the UPS can be to other equipment, especially the interferometer.

We defined the maximum allowable magnetic field at 60 Hz from any electronic device to be 0.4 nT, which is one tenth of the root mean square 60 Hz magnetic field during iLIGO science runs.

For magnetic field measurements, we used two 500 Watt lights (to simulate the PSL load), a Bartington magnetometer (mounted on a tripod), and the UPS (placed horizontally and face-up on a plastic bin).

During preliminary tests, we found that the system's on/plugged-in and off/plugged-in configurations produced similar magnetic field magnitudes. Therefore, the UPS must be placed at its minimum distance whenever the device is plugged-in (and either on or off).

Next, at 1m, we measured the magnetic field at three different angles relative to the physical center of the device. Of these measurements, The lowest value was 55% of the highest value. The magnetic field at 60 Hz was strongest when the magnetometer was aligned with the device's front (face with buttons) left edge, and the remaining measurements were taken at this angle. 

The final step in determining the minimum distance was measuring the attenuation of the device's magnetic field with distance. To minimize noise caused by surrounding electronic devices, I collected data in the VEA of End X instead of in the LVEA. I took data from 3 to 39 feet, with a constant interval of 3 feet. At each distance, I used Diagnostic Test Tools (DTT) to record the power spectra of the magnetic field when the UPS was unplugged and off and when the UPS was plugged-in and on. I took two data sets--both were numerically similar.

The data was slightly noisy, so I used Grace to perform a linear regression on, at 60 Hz, the natural log of the magnetic field  vs. the natural log of the distance. I found the fitted curve to be described by:
 
y=(170.579)x^-1.739

In conclusion, when y is 0.4nT (see above), x is about 33 ft -- the minimum distance.

The attached plot shows the UPS magnetic field attenuation.

Here is a link to the UPS at the LIGO Hanford Observatory: http://www.apc.com/resource/include/techspec_index.cfm?base_sku=SUA1500R2X122

Christina Daniel, Robert Schofield

I did some math to figure out how much ITMX, ITMY and BS may have been moving (in a frequency band of 0.1-1 ish Hz) in their angles according to fluctuation of the DC light observed at the dark port when the Michelson was locked.

(Summary)

Wednesday night (August 27th)

• The dark port DC (ASAIR_B_LF) flucutated by 16% of the bright fringe when the Michelson was locked on a dark fringe.
• ITMX(Y) may have been moving by 11 urad or 22 urad in peak-to-peak.
• BS may have been moving by 5.7 urad or 11 urad in peak-to-peak.

Friday night (August 29th)

• The dark port DC (ASAIR_B_LF) flucutated by 1% of the bright fringe when the Michelson was locked on a dark fringe.
• ITMX(Y) may have been moving by 2.8 urad or 5.6 urad in peak-to-peak.
• BS may have been moving by 1.4 urad or 2.8 urad in peak-to-peak.

(Some math behind it)

Suppose the Michelson is locked on a dark fringe. If an ITM is misaligned by Ψ, this introduces a displacement and tilt in the reflected beam with respect to the one from the other ITM at the BS. The displacement is x = 2 L Ψ and the title is ϑ = 2 Ψ where L is the distance from the BS to the ITM. So we get a small amount of 01 or 10 mode at the dark port on top of the 00 modes. Since the effect on the resultant 00 mode in its power is proportial to 4th power of the displacement and tilt, we assume the 00 mode to vanish because of the locking loop. The only residual we obtain at the dark port is the 01 or 10 mode whose field can be written as

E₁₀ = 1/sqrt(2) ( x/w₀ + i * ϑ / ϑ₀),

where w₀ is the waist size and ϑ₀ is the divergence angle respectively. A factor of 1/sqrt(2) upfront comes from the BS reflection. If we plug the definition of x and ϑ into the equation, we get

E₁₀ = sqrt(2) ( L/w₀ + i / ϑ₀)  Ψ.

Squaring the above, one can get the dark port power as

P = 2 ( (L/w₀)²+ (1/ ϑ₀)²)  Ψ²

Note that P is already normalized by the input beam power or equivallently the bright fringe. The Rayleigh range of the beam around the BS is roughly 210 m (if my math is correct). This gives a waist size of 8.4 mm and divergence angle of 40 urad.  The ITM-BS distance L is about 5.34 m where I averaged out the Schnupp asymmetry. So the dark port power can be now explicitly written as

P = 1.24 x 10⁹  Ψ²

This is the equation I used for deriving the numbers listed at the very top.

For example, if one wants to explain a 16% DC light fluctuation observed at the dark port by an angle deviation in ITMX(Y), the misalignment should be Ψ = sqrt(0.16 / 1.24 x 10⁹ ) = 11.4 urad. In the case of the BS, the effect gets twice bigger due to the fact it affects both X and Y beams at the same time in a constructive manner.

Patrick, Jim, Dave

we reconfigured the conlog to get the unmonitored number from 3000+ down to zero. We moved the susquadtst targets into the target archive. We had to hand edit the pv_list.txt to replace H1:ODC-CAL_PCALX_* channels with H1:CAL-PCALX_*. There is a bug in my include list generator python script which did not handle the top-names correctly, needs a rewrite using the autoBurt.req files instead.

on opsws1.  Please don't disturb the matlab session.  Except for watchdog trips, all is automatic.

The X-end controller for the baffle diodes was still one of the early units with parts missing (BO at the time). Swapped S1302233 with S1400075; and updated the Beckhoff to reflect these changes. It is now possible to adjust the gains remotely.

It seems like the damping loops are OK for the SRs.  Attached are screenshots comparing each of them to the corresponding PRC optic. I didn't adjust anything on SR2 or SR3, on SRM I  turned off FM1 on L, to match the configuration of the PRM damping loops. I also increased the pitch gain from -2 to -3, since there was more pitch motion on the SRM, the resulting spectra are in the screenshots below. 

SR3 T+V have extra noise at around 13.6 Hz and 16.25 Hz respectively.  This is there with damping on and off, and there are no resonances predicted by the model at these frequencies.  Jeff suggests that these could be HEPI resonances. 

To do this, We had to turn on some ISI loops on HAM5.  To do that, Jamie had to edit the guardian so that now we can request ISOLATED_ROBUST.  Hugh also had to reset the CPS targets.

Based on the top stage osems, it seems like the motion of the SR cavity should be comparable to the motion of the PRC, so large motion of the optics shouldn't be an impediment to locking the SRC anymore now that HAM5 has some form of isolation. 

LVEA is Laser Hazard

08:29 Hugh - Going to End-X to check HEIP pump controller and put H2 actuator into run mode
09:14 Filiberto – In LVEA working on cable cleanup around the spools
09:36 Richard – In LVEA
09:45 Praxair Nitrogen delivery
09:47 Jeff K. - Going to End-Y to check the ION pump status
09:56 Peter & Rick – Going into the H1 PLS enclosure
10:07 Richard – Going to End-X
10:10 Jodi – Going to End-X and then to End-Y to check property tags
10:17 Hugh – Going to End-X
10:35 Betsy & Travis – Going into the LVEA to look for parts
10:35 Kiwamu & Lisa – Checking out electronics at ITC6
11:10 Unifirst on site to change out entryway mats
11:26 Bottled water delivery to site
11:50 Check DR chiller water level. Level is good
12:29 Filiberto – Checking for ground loops on SRM
13:00 Cris – At End-X
13:03 Karen – At End-Y
14:40 Wire delivery for Richard 

With the new Parker Vlave on H2, ran Range of Motion and Linearity tests on the system.  Before I could do that I saw that a zeroing of the IPS was in order.  Some sensors were too far out to really test the range of the Actuator.  Rezeroing the IPS will change the Cartesian Basis Positions and therefore the loop targets.  I trended the Positions back to IFOX and then applied the free floating to Isolated deltas to the new near-zero positions for RY & RZ.  Remember too that EndX had the large Ry tilt for the TMS pointing.  Keita turned off the pitch loop and then adjusted the TMS accordingly.  Anyway, straight forward shift it was that and is now this:

Guardian only holds the RZ and RY targets(at EndX;) the other DoFs are locked to the free hang position at the time of Isolation start so will drift around with the usual HEPI hysteresis.  The other targets I just grabbed and are really only for reference.  If the free hanging position is terribly far from these numbers (no, I don't know what too far is..) something may be amiss.

Back to the IPS zeroing, the mechanical stops on the HEPI Actuators (not adjustable) were mostly compatable with the IPS zeroing.  ROM was 1.0mm for all Actuators except H2+, H4+ & V1+; H2+ & V1+ managed 0.9mm, and H4+ made 0.8mm.  Linearity test results are attached; Jan results in first plot, today's in second.  The new valve does seem to have less umph (from a new batch hot from LLO calibration) dropping a little less than 20% compared to the .  Still, the position loops close and are stable.  I have some other evaluations to do and will update.

The new H1 ITMs ROC (ITM03 and ITM11) are similar to the ones in L1, but they are swapped (the wavefront error is larger from X than from Y). 

Based on  T1300954 (table 3) and Hiro's wisdom, the effective ROCs of the H1 optics, as measured in reflection, going through the bulk, are:

R_ITMX (ITM03) = 1939.3 + (-10.92*2*1.457); 
R_ITMY (ITM11)= 1939.2 + (1.56*2*1.457);

By looking at the L1 data in single bounce without TCS (below), one should expect something like ~20% mode mismatch for X and something somehow better for Y.

L1 Mode mis-match:
NO TCS:
ITMX    14.5%
ITMY    22%

Even with an input beam perfectly matched to the PRM, I would expect something like:

modematching asX with OMC = 0.8408
modematching asY with OMC = 0.91229

Reset WD counters on HAM5, ITMX, BS, and ITMY. 

J. Kissel, J. Worden, K. Ryan

Just picking up the ball from Borja's charging measurements -- I wanted to be sure I understood the current status of the vacuum before I got started. I attach minute trends the past 100 days of the end-station ion pumps. We expect and understand the behavior seen in ETMX, but only the B channels on EY appear to be reporting sensible information.

Current Status:
H1 EY
   Ion Pump valved IN (gate valve on IP-11 is open to the chamber)
   Turbo pump is valved OUT (closed to chamber)
This status has been the same since Tues Aug 26 13606.

Remember, each ion pump has two circuits, A and B, of which we monitor (in EPICs) both Current (I, in [A]) and the Electric Field (E, in [kV]). It looks like, at EY, these monitor signals for circuit A are broken -- both I and E channels are reporting what appears to be an *inverted* current signal. The B channels make sense, in that the current matches the expected behavior (current [proportional o pressure] is low when valved out [closed to the chamber, pumping on a small volume], high when valved in [open to the chamber, pumping on a large volume]). What's also curious is that the B channel's field is at a roughly constant 7 [kV], where as for EY A , EX A and B, they're consistently 3 [kV]. John is reasonably confident that this is a problem with the monitors, and not indicative of any problems with the ion pumps.

H1 EX
   Ion pump valved OUT (gate valve on IP-12 is closed to the chamber)
   Turbo pump is valved IN (open to the chamber)
EX had had failure trouble with several of its B circuit's power supplies, which is why one sees changes between 2014-Jul-20 and 2014-Aug-23. The log indicating the fix is LHO aLOG 13566.

After bleeding/flushing since Friday should be good to go.  I'll run some static test now to confirm everything is okay.  The valve was replace due to a leak, not from a performance perspective.

- Jason is working on HAM4 and HAM54 OpLev rough alignment.  
- Mike, Gerardo, and Jeff K. continuing the TM Charging Experiments in the corner and end stations. 
- Jodi is recording H1 PEM tilt meter and seismometers serial numbers.
- Betsy & Travis working on the 3IFO Quads in the West Bay.
- Filiberto general cleanup in the LVEA and pulling wires for cameras & OpLevs.
- The commissioning crew is working on OMC alignment.
- Jamie doing a core upgrade to the Guardian code. This will require a DAQ restart.
- Hugh is working on HEPI End-X restart after a Parker valve replacement. There are new Alarm Handlers for HEPI which will be added to the alarm system startup.
- Peter is working on the PMC alignment of the H1 laser. ISS work has been deferred until next week.
- Jonathan will be doing a reboot of the GC systems and the aLOG.   

No ISS noise report will be generated this week as the ISS is still acting up - I didn't have the opportunity to look at it last week.  The alignment into the PMC should also be looked when the time opportunity arises.

The relative power noise measurement is consistent with the last measurement taken and is similar to the reference measurement on file.  Both are well within the requirements for the laser.

For frequency noise measurement the control signal looks nominal.  The error signal is noticeably different from the reference measurement for some reason.  It might be alignment related but will require checking.  It is known that the alignment into the reference cavity, and perhaps onto the RF photodetector, is slowly deteriorating.  This in turn is suspected due to a problem with the frequency shifting acousto-optic modulator.  That will also be looked at when time is granted by the integration crew.

The beam pointing measurement does not make sense compared to the one previously performed.  The numbers report as zero and the plots are significantly off.  The calibration age and control signals look comparable to the previous scan.  The error slopes in the current measurement are significantly off, which would explain the problem seen with the plots.
A second measurement (dbb_pnt-002) was done.  This measurement looks more like the others on file.  Not sure what was wrong with the first measurement other than perhaps the calibration age (~20 minutes) was too old?  The second measurement has calibration ages of less than 10 minutes.

The mode scan measurement is practically identical to the previous one.  Higher order mode content and power the same at 58 and 4.6% respectively.

The aLOG will be restarted at 10am pacific today for regular maintenance.

Please save your entries prior to that point in time.

[Dan, Nic, Koji]

Summary

The OMC alignment servo was commissioned today.

• The sensing matrix (between OM1/2/3 P/Y to OMC QPD A/B P/Y) was measured.
• From OM3 to OMC QPD A/B measurement, the ratio of the spot sizes on the QPDs were inffered.
• From the geometry of the OMC and the spot size ratio, the alignment input matrix was set
  such that the beam angle and position with regard to the beam waist becomes the servo basis.
• From the sensing matrix measurement and the input matrix, the output matrix was set such that the actuation is diagnalized in terms of the servo basis.
   
• The servo loops were engaged and the spot on the QPDs were successfully controlled.

To Do

• Open loop TF measurements
• Noise measurement (inloop & free running)
• Servo shape tuning
• Confirmation of the servo diagonalization
• Dither alignment implementation

1. Sensing matrix

The ISC alignment input of OM1/2/3 was excited at 3.9Hz and 2.9Hz for Pitch and Yaw, respectively.
The spot motion was read out by QPDA and QPDB.

Measured sensing matrix was

| H1:OMC-ASC_QPD_A_PIT_OUT |   | -2.21e-3 +3.05e-3 -1.35e-3 || H1:SUS-OM1_M1_LOCK_P_IN1 |
|                          | = |                            || H1:SUS-OM2_M1_LOCK_P_IN1 |
| H1:OMC-ASC_QPD_B_PIT_OUT |   | -1.05e-3 -1.64e-3 -6.24e-4 || H1:SUS-OM3_M1_LOCK_P_IN1 |
 
| H1:OMC-ASC_QPD_A_YAW_OUT |   | +1.11e-3 -3.13e-3 +1.84e-3 || H1:SUS-OM1_M1_LOCK_Y_IN1 |
|                          | = |                            || H1:SUS-OM2_M1_LOCK_Y_IN1 |
| H1:OMC-ASC_QPD_B_YAW_OUT |   | -6.38e-4 -1.86e-3 -9.55e-4 || H1:SUS-OM3_M1_LOCK_Y_IN1 |

2. Spot size ratio

Since OM3 is a flat mirror it is straight forward to use it as a scanner to infer the beam size on the QPDs.
Unfortunately, I don't have the absolute calibration of the OMs, only the ratio of the beam size was obtained.

The geometrical arrangement of the QPDs and OM3 are found in the attachement.

(H1:OMC-ASC_QPD_A_PIT_OUT) = Sqrt(2/Pi)/omega_A * [(2 L_QPDA) * A_OM3_PIT(f) * (H1:SUS-OM3_M1_LOCK_P_IN1)]
(H1:OMC-ASC_QPD_B_PIT_OUT) = Sqrt(2/Pi)/omega_B * [(2 L_QPDB) * A_OM3_PIT(f) * (H1:SUS-OM3_M1_LOCK_Y_IN1)]

3. Input matrix

(TO BE FILLED)

4. Output matrix

(TO BE FILLED)

5. Servo control

The servo filter did not have the slow integrator which surpresses the DC component. An integrator below 0.1Hz was added to FM6.

[Fil Arnaud]

Few days ago I realized SRM top mass dials were moving more than usually, so I took a spectra this morning which shows noise at around 1700Hz for LF RT SD and T3 osems signals. Those four osems are using the same quadrupus cable from the flange to the sat box. The spectra compares those four osems with SR3 RT SR3 SD SRM T1 and T2, which shows a peak at 1700Hz but much less higher.
We tried powering down the AI chassis and the coil drivers several times, which didn't fix the issue. I don't recall we powered down the AA chassis, so that might be the next thing to try. 
To be fixed.