• To_Do_List

This is the Phantasmical To Do list for the 40m lab:

--In-lock alignment (This is a big one)

• We think we're plagued by alignment drifts, and it's hard to tell where it's occuring. We shouldn't wait for wave-front sensors on this one, but maybe instead start thinking about a DC-wavefront sensor system (ie, dithering and demodulating in a front-end). Someone should start working on some RF wave-front sensors, though.

--Get the AutoRun GUI working.

--LSC code upgrades

• Clean up the code, add state vectors for the AutoRunGUI,

  MatrixCopy fix, fast (or slew rate limited) input-matrix ramping, more things

--measure all RF phases in various stages of lock, especially full lock.

--Transfer function characterization

• This follows the item above, and everyone will be interested in the results. We need to characterize the: RSE peak optical spring coupled cavity response all open loop gains/cross coupling of signals frequency noise coupling. Finesse has shown some unexpected transfer functions to places other than the DARM signal; we should investigate these. other CARM transfer functions to non-traditional signal ports

--Full output matrix diagonalization

• 5x5?

--Start thinking up some other schemes (lower RF frequencies, no-bang locking)

--Differential demodulation ? or double demodulation?

Now we are using less noisy one of 133 or 199MHz demodulation. Should we use both for double demodulation or just leave them? In any case, we should investigate why SP and AP is less noisy with 133MHz demodudlation and why PO is less noisy with 199MHz demodulation.

• Suspension dewhitening filters (probably doesn't matter at 4 kHz)
• Isn't this already done by David Malling?

--Ground loop

Power supplies, racks, optical tables, chambers, LSC PDs, cables etc. ** <b>Get rid of all these long cables to the control room !!</b>

Main commissioning tasks (all **) - suspension diagonalization & gain optimization for all suspensions:

• coil balancing, F2P filters, POS<->ANG decoupling. Appropriate filters, bandstop filters on all OSEM and oplev damping loops. Dan.

- Commission common mode servo analog path.

• Osamu.

- Mode matching from IMC -> IFO.

• Osamu.

- Develop LSC scheme for full lock, reduce CARM offset to 0,

• automate, characterize. Osamu, Rob, all.

- Noise budget, picking up where Ryan left off.

• Dan, Monica, with help from Rana & Vuk.

- time-domain simulation, extrapolation to AdLIGO.

• Monica, with help from Hiro & Matt.

_ Controls: - Replace c1losepics/c1iscepics temporary cpu with permanent one

• that doesn't have a DHCP server running! Rolf, Alex, Jay. **

- c1susvme2 sometimes loses time synch.

• Alex?

- Replace framebuilder RAID array with fiber link to QFS system.

• Rolf, Stuart, Larry.

- LSC front end cpu starts to creep up towards 61 usec.

• 16 Hz and harmonics appear everywhere. Rob, Rolf, Alex. **

- QPD Whitening boards: whitening filters aren't switching.

• Ben, Alex. **

- Protect the front end code against NaNs from ezcademod

• and we need to prevent ezcademod from spitting out NaNs (and find out what causes it to do so in the first place). Rolf, Rob.

- Vacuum EPICS screen: TP on/off logic; TP readout;

• EPICS state code for reading out TP3 and IPs, and for protecting/closing V1 if TP1 starts to fail. Jay, Dan.

- Front end code slows down considerably when AWG is running?

• Hasn't seemed to be a problem lately...

- LSC rack power is inadequate. Redo the system, add Sorensens?

• Jay?

- Coupling between LSC IQDemod boards and whitening boards:

• Add power regulators. Add heat sinks. Ben. **

- Convert all RFPD DC signals to their LSC PD Interface version,

• eliminate deticated DC cable (which causes ground loops). Ben. **

- The new fiber timing system from Sander seems to be working ok.

• When the sites convert to a new system, we should too!

- Still have big 60 Hz problems.

• Draw up ground loop plan, including proper grounding of rack power supplies; implement. Ben. **

- Fast DAQ signals from 1Y2.

• Are they all being read in and logged correctly, falling in meaningful range? Ben.

- Linux framebuilder?

• Rolf? Alex?

- Are all controls drawings (PDFs) up-to-date on Ben & Jay's web sites?

• LSC? ASC? SUS? Ends?

_ PSL: - How well is ISS running these days? A measure of RIN is needed;

• it would be nice if we had SOME continual monitor of performance. Osamu: Wait.

- When MZ control signal saturates and falls out of lock,

• the ISS saturates, and MC falls out of lock. Solution is to toggle MZ servo. There should be an alarm to warn us of impending MZ and ISS saturation. Dan?

- Get more light onto ISS PDs with new pickoff beamsplitter. - Commission post-MC ISS PDs?

• Wait, until it becomes clear that intensity noise is limiting us.

- The PSL triped off twice in last 6 months for no apparent reason.

• Resetting the PSL was poblematical, requiring manual adjustment to PA shutter. Is the procedure at fault? Also, do our MOPA power supply front panel controls work? Osamu and Rich.

- Should we get a new TT ISS board?

• The one we have is a prototype, and it is clear from recent work at LLO that the performance can be improved dramatically with some effort.

  http://www.ligo.caltech.edu/~abbott/files/T050135-00.pdf Wait, until it becomes clear that intensity noise is limiting us.

- Is the MINCO temperature controller servo set correctly?

• Do we still have temperature fluctuations on the PSL FRC with ~ 20 minute timescale? Need to get the MC RF sideband transmission monitor system working.

_ MC, MZ: - The MC RF sideband transmission monitor system is not working,

• due to a bad lockin amplifier. Should we buy a new one (many $K's), or design a dedicated board like the PMC servo? Osamu: now seen to be a relatively minor problem.

- How about that RF multiplier circuit?

• Does it still make sense to make it work, either for replacing the existing RF signal generators, or as part of a servo to stabilize the MC transmission of RF sidebands? Wait.

- Replace MC servo board with newer version? Its on the way. - MC WFS gain and UGF was turned way down (UGF=0.6 Hz).

• Need to minimize ANG->POS couplings on MC suspensions and then try to get it back up. Dan, Osamu. **

- L7 mixer chip for MZ servo.

• Osamu: wait.

- Add phase-correcting Pockels cell actuator for

• higher-bandwidth MZ loop? Will proabably be needed for AdLIGO, accd to Kentaro.

_ SUS, LSC, ASC: - OSEM sensor glitches: still have them?

• They were isolated to be originating in ICS100b or the VME crate itself. Due to crate 5V power supply?? Rolf has a fix, used at HEPI?

- OSEM problems diagnosed by checkosem script.

• Why are ETMX and ETMY OSEM monitors different from the rest? Why is there an abnormal sign flip on ETMX side?

- Can't put excitations into SIDE OSEM channels.

• Jay, Rolf?

- New LSC RFPDs (4+spare). Install AP166 first.

• Ben, Osamu. **

- Get fast triggered mech shutters for AP and SP.

• The EOS on MCR seems to be working well; keep it. Ben.

- Commission ASC system servos:

• - on IPPOS/IPANG or TRX to PZT steering mirrors. - Is it possible to stabilize some useful degrees of freedom using 33 MHz WFSs? Wait, until it becomes clear that angular noise is limiting us.

_ Computers: - We can't run EZCA and/or TDS scripts on the linux operator boxes,

• only on solaris. Several MEDM problems on linux (PVinfo, snapshot, etc don't work). DTT often loses time synch or crashes altogether on linux. DTT trace colors don't work on linux. Foton doesn't work at all.

- We can't print to hp2550 from any of the operator consoles except linux3.

• Alex. **

- Review the stuff in ALH to see if

• important things are missing or unimportant things are present.

_ DC readout (all **): - Finalize design of OMC.

• Rob, Mike.

- Finalize design of DC PDs.

• Ben, Mike.

- Review Mike's parts list.

• All.

- Get final budget, and order parts!

• AJW, Mike.

- update DC detection technical design document.

• AJW.

Other: - Bypass STACIS on Y arm (done, on ETMX, ITMX).

• Steve.

- beamline as-built documentation. Update ACad drawings.

• Mike, all.

- cranes - overheating, failures.

• Temporary solution: don't run in standby mode. Ben.

- gutters on building.

• Steve.

- replace leaky valve on roughing pump.

• Steve.