Elli, Nergis, Daniel, Evan

Today we did a preliminary measurement of the Schnupp asymmetry to be 9.0cm +/- 1cm.  We injescted a beam from the auxiliary laser on IOT2R which can be offset in frequency from the main laser.  We measured the power of this beam at the AS port using a 1611 photodiode on ISCT6.  With the michelson locked to a bright fringe, we measured the variation of auxiliary laser power with frequency at the AS port.  Due to the Schnupp asymmetry, the power should change as the auxiliary laser offset from the carrier increases as cos(scnupp_assymetry*2*pi*f_offset/c).

By fitting a curve to our measured data, we can get an estimate of the Schnupp asymmetry.  I did a fit using least squares fitting to a quadratic to get 9.0cm +/-1cm Schnupp asymmetry.  The measured data and curve fitting codes are attached.  Evan hopes that we can reduce our error estimet by doing the curve fitting more elegantly.

Sheila, Keita, Nergis, Evan, Alexa

With our beloved x-arm back, we began the alignment process:

1. Aligned TMSX with ITMX baffled PDs (and ETMX misaligned). For reference:

2. Aligned ITMX with the ETMX baffle PDs (and ETMX misaligned). Again, for reference:

Yes, the ETMX baffle PDs have a negative voltage!!

3. We realigned ETMX by hand. We had to increase the max pitch PV limit from 440 to 500. We hope those were set arbitrarily; the DAC was not saturating with these higher slider values. We were able to lock the x-arm on green to a buildup of 1.4-sih, which is good.

Unfortunately the green wfs servo did not wok and would misalign the arm. We did have to turn on the ITMX ISC_INF_LOCK and MO_LOCK, and TMSX M1_LOCK filters. Unfortunately this was not the culprit. It appeared that the wfs error signal had an offset, but we did li. We want to continue with locking. 

Alexa, Sheila, Nergis, Evan

We took a quick measurement of the X arm loss using the same technique as LHO#15919. For ASAIR_A_LF, we have P_on = 1267(5) ct, P_off = 1293(3) ct, giving an equivalent loss of 78(18) ppm for the ETM.

Today I spent sometimes setting up the calibration filters for LSC DARM in h1oaf. It should be functional now.

What I did:

• checked the suspension responses
  • There had already been some suspension filters in the DAM calibration path in oaf. It seems that the ones installed in OAF are more damped, compared with the latest damped suspension model. I did not try to change the existing filters this time as I did not think it was crucial.
  • The suspension model I used for the comparison was generated by a matlab function, generate_QUAD_Model_Production with a damping by dampingfilters_QUAD_2013-06-14.mat in SVN.
  • See the first attached png and fig files for the comparison. The dashed lines represent the suspension models and the solid lines for the ones actually installed in oaf.
• adjusted the DC gain of each suspension stage.
  • ESD gain was adjusted by using the new definition of alpha (e.g. T1500036-v1). I used the following equation to derive the force coefficient
  • dF/ dV = 2 x alpha x G^2 Vbias
  • where alpha = 2e-10, G=40, Vbias =9.5
  • The DC gain of the rest of the stages were also adjusted such that they match the suspension models.
• adjusted the DARM error signal path.
  • Currently the cavity pole is set to 389 Hz. We should correct it once we measure the actual cavity pole with the interferometer fully locked.
  • The DC gain of the DARM error path is set to 1e-6 as it was already calibrated into um for ALS diff.

Also, the second attached png is a screen shot of the latest DARM calibration setup. This is set up for a single ETM configuration where either ETMX or ETMY is not in use. If one wants to feed DARM back to both ETMs, an extra factor of two should be added somewhere. Note that the L1 (UIM) stage currently has a gain of 0.5 as shown in the screen shot n order to simulate the digital gain in SUS-ETMX_L1_LOCK_L_GAIN.

Following the RCG2.9 upgrade yesterday, I have created SDF files for the following systems: IOP, PEM, SUSAUX, TCS, CAL, PSL, ODC. In each case I have made all channels monitored, and removed the obsolete FEC-nn_GRD_[ALH,SP,RB] channels from the safe.snap sdf file. Modified files have been commited to SVN with the exception of CAL (I get an svn error with this working directory).

Latest SDF_OVERVIEW MEDM screen shot attached. All monitored systems are now green for channel matching.

S. Biscans, J. Kissel, N. Mazumder, H. Paris, H. Radkins, B. Shapiro, J. Warner

After an extremely productive two weeks -- thanks to the new years present of Narwita, Seb, Hugo, and Brett all arriving within the same few days -- I figure it would be good assess where the LHO SEI team's priorities lie from here on. In particular, what *other* things that we could be doing to improve *all* the platforms instead of continuing to bang our head  against the HAM3-0.6-[Hz]-feature wall. Here're the remaining activities, sort of prioritized, and split into "Improve the chamber noise performance" and "improve the maintainability / extensibility" groups.

Improve The Chamber Noise Performance:  
     All Chambers                                                 Benefit to IFO
     - ST 01 L4C Feed Forward (all 6 DOFs),             improve 1 to 10 [Hz] performance
     - Sensor correction gain matching (all 3 DOFs),    improve 0.08 to 3 [Hz] performance    

     BSCs Only
     - Z to RZ subtraction,                            reduce BSC optic's yaw below 0.08 [Hz]  
     - Implement Slow MICH,                        reduce MICH velocity, improving lock acquisition 
     - Finish ITM HEPI Z to RX/RY Tilt Decoupling,     reduce BSC optic's yaw below 0.08 [Hz]    

     HAMs Only
     - HAMs 2,3,4,5 Isolation Loop Gain Increase       improve 0.5 [Hz] to 20 [Hz] performance
     - Continue HAM3 0.6 [Hz] feature investigation        improve 0.6 [Hz] performance 

Improve the Maintainability / Extensibility:
     - BSC-ISI Noise Budget Model
     - HAM-ISI Noise Budget Model
     - HEPI Noise Budget Model
     - Assess guardian vs. watchdog robustness of bringing all chambers to OFFLINE from FULLY_ISOLATED
     - Put MATCH OUTPUT channels on Sensor Correction overview screen
     - Storing more than just RZ on HEPI alignment
     - Hook IOP SWWD signals up to ISI USER watchdog
     - Install HEPI saturable integrators
     - Remove HEPI / ST0 L4C Sensor Correction path from ISI models
     - Differential Pump Pressure signals are noisy possibly from poor electrical grounding
     - Switch ETMX to using differential pressure signal
     - Assess whether switching to differential pressure affects platform noise performance

Removed one of the PEM AA chassis to troubleshoot some bad channels. Troubleshooting/repairs is taking longer than expected but should have the unit back in service sometime tomorrow morning.

D1001421 Serial Number S1001053.

Kyle and Gerardo opened the XEND to the beam tube today. 

The turbo was valved out, the ion pump valved in, and the gate valve to the tube/80K pump opened.

Plot attached. The pressure has fallen from 1e-6 to 8e-8 and is still moving the right way.

(Kyle R, Gerardo M)
Removed and replaced the annulus ion pump.

NOTE:
Currently there is a pump cart pumping this annulus system, will remain there until system pressure is down enough to turn on the ion pump.

J. Kissel, K. Izumi

Kiwamu is making sure the online calibration filtering (currently in the "OAF" model, will eventually be in the "CAL" model) is reasonably up-to-date. In doing so, we discovered that the two ETMs have different damping loop filters installed and ON. Most filter modules are as expected, according to the original, low noise, Level 2.1 quad design (see LGO aLOG 6760). However, in FM3 of the L and Y banks of both ETMX and ETMY, there are filters called "resg1" and "+12dB" respectively. They are ON only in ETMX.

After a little digging down memory lane, we recalled that in attempts to get ALS DIFF up and running last time (see e.g. LHO aLOG 15025), before we lost the arms, we had copied over LLO's damping filters' differences at the time -- described in detail in LHO aLOG 14959. However, as indicated in LHO aLOG 15037, having the filters constantly ON never got captured in any sort of configuration control, because ALS and LSC control was bouncing between using ETMX and ETMY depending on the functional-state and state-of-confusion for each test mass.

We have now turned both FM3's of L and Y filter banks ON, and changed the DAMP_STATE_?_GOOD state to match the current state with those ON. We have not yet captured a new safe.snap in this configuration, but we'll do so ASAP.

A note -- the ITMs do NOT have these "bonus" LLO filters installed, so FM3 is therefore OFF.

Replaced bad projector lamp on left side projector in control room.  

NOTE: The lamp socket internal to the projector has badly overheated and the plastic mount that holds the socket pins has lost it's integrity. If you smell smoke in the control room, this projector should be powered off.  This seems to be a common problem with these projectors.

For the Schnupp asymmetry measurement, one of the patch panel connectors on ISC R1 (by the PSL) is now wired to another patch panel connector on ISC R3 (by HAM6). The wiring is as follows:

• Existing patch cable: ISC R1 #11-4 → ISC C4 #2-4
• New 1 m cable: ISC C4 #2-4 → ISC C4 #5-6
• Existing patch cable: ISC C4 #5-6 → ISC R3 #15-6.

Initially, all these ports were labeled as "spare" and most of them were terminated.

The connector on ISC R1 will be driven by an rf signal from an IOT2R PD. The connector on ISC R3 will go into a spectrum analyzer.

DAQ was restarted to sync up with temporary h1iscey model change which was applied in the last hour.

We only restored PIT of HEPI2 (H1:HPI-HAM2_IPS_RY_SETPOINT_NOW) yesterday, but there was a change in ROLL (RX) on the order of 10 urad that was not restored, which might affect the input pointing.

Also, there was a jump in ROLL in HEPI3, again on the order of 10 urad, which would affect POP and ALS beam position on ISCT1 as well as POP sled in HAM3.

These DOFs were brought back to pre-maintenance levels.

I don't know/remember why, but it seems that a new set of angle setpoints is made for HEPI such that the system starts new with free-hanging position after each restart. Seems like this free hanging position changes over time.

Since any change in HEPI angle (RX, RY and RZ) on HAM2 and HAM3 would affect many things related to the alignment, most notably pointing references like IM4 transmission QPD and POP sled, it's a good idea to keep the set points unchanged over multiple restarts.

Jim, Dave: WP5003

This morning we upgraded H1 FE and DAQ to RCG2.9. First the DAQ was upgraded and restarted. Then FE startup scripts were changed, model startup scripts changed.

Then a "make installWorld" was ran to install the models which were compiled yesterday. The H1.ipc file generated yesterday was re-installed.

We tested a reboot-restart first on a non dolphin FE (h1susauxh2) and then on a Dolphin FE (h1seib1).

We then restarted all frontends in the MSR by power cycling the computers, and end station frontends by rebooting the computers. We ended up having to powercycle h1iscex because it got stuck in reboot. In the MSR when we were restart testing, h1susb123 got stuck on reboot and needed a power cycle which Dolphin crashed the other MSR machines.

We got to a stable system with DAQ and FE reboots proceding correctly. We had 6 front end IOP models with large IRIG-B excursions into the 1000-2000 counts. The h1oaf0 IOP took 4 hours to return to normal IRIG-B range. One IOP went below zero (999998) which caused IPC errors on models receiving its channels. This fixed itself in about 10 minutes.

We noticed a single ADC error on the h1ioplsc0, which was cleared with a DIAG_RESET.

We noticed the DAQ frame size is smaller now. For science frames 670MB to 610MB (10% reduction) and commissioning frames 1.2GB to 1.0GB (20% reduction). We suspect new common models are the reason for this.

I linked Jamie's SDF_OVERVIEW MEDM screen to the SITEMAP under the GRD section. We are configuring the IOP, PEM and PSL systems.

This closes WP5003