• Project_Planning_Pre_2017

40m work plan (edited Jun 2017)

Planning

This google document collects some project ideas for the short/medium/long term.

Some ongoing projects (in rough order of priority), updated on Jun 5 2017:

• DRMI locking + noise budgeting
• Characterization + improvement of SOS drive chain electronics
• BHD @40m - design + modeling
• Finesse modeling of various IFO configurations for comparison to measurements
• WFS sensing matrix measurement
• MCL optimal feedback loop design
• Measurement of losses in recycling cavity - inject beam from AS port?

Long term future

• The 40m could be the prototype interferometer for the third generation interferometer
• In particular, if we decide to use Silicon test mass at longer wavelength, we want to accumulate experiences with the new type of devices (mirrors, crystals, noises, laser stabilization, etc)

• This project should start once the baseline concept of the third generation IFO is fixed and the basic table-top R&Ds show supportive results.

• What kind of tests do we want to do at the 40m? Quantum? Thermal?

Mid term future

• How can we make the 40m useful for aLIGO?

• TCS testing with the tip-tilt suspensions. Which tip-tilt? What to be tested? What to be measured? TT+IFO? TT+OMC?
• TT sus improvement. Request help of LIGO Engineering. Make it tall. Run shaker tests. Once they are OK off-line, replace the TTs in-vacuum.
• Scattering measurements. Characterize the low to high angle scattering to investigate the relationship between the phasemap and the scattering. Utilize the advantage of having ATF-coated mirrors and (sort of) long arms. This is related to the mirror cleaning.
• OMC resurrection/upgrade. What's the motivation?
• Control related topics?

Near term targets

• How to make the lock indefinite.
• What to do with DRFPMI? (Transition to 1f signals, sensing matrix, open loop TF, cavity pole measurement)

• Implementing LSC feedforward cancellation (e.g. actuation FF MICH->PRM (seems OK now), MICH->SRM (not great)

  • MICH->DARM, PRCL->DARM, SRCL->DARM

• Can we write a paper only with the locking of DRFPMI? How? Do we need to combine it with something else?
• Modulation cancellation technique to further reduce CARM coupling into 3F signals during ALS CARM/DARM reduction.
• Vent
  • Pre-vent: ifo loss measurements (PRG, Arm refl, Arm scans, Loss measurement with the spot position scanned)
  • Pre-vent: Any independent measurements? (Scattering, spot cameras, etc)
  • Venting: Arm mirror wiping, arm length change? Just adjust the difference? Do we change the arm length concept?
  • Venting: Any other modification? Do we want a scattering measurement setup?
  • Venting: Cold cathode, convectron installation.
  • Post-venting measurement.
• ISS

Paper worth topics

• DRFPMI?
• Delayline Freq Discriminator / Phase Tracker
• Scattering characterization
• Modulation cancellation
• Other control related topics (e.g. CESAR, ESCOBAR, ALS FOL)

Old materials. To be merged to the above info

This should be kept up-to-date. This is an overview of our near-term goals. We can link to other TODO lists from here.

PRMI commissioning

• PRMI locked!
• Investigate triggering (trigger on POP110 instead?)
• What is the correct normalization?
• Lower Q on Vio2 filters
• Finish updating IFO configure scripts, medm "restore" (Jamie)
• OSA modulation depth measurements at:
  • REFL
  • AS
• Power budget at all available ports, include 1f(22)/2f(110)
  • PRC gain

• Oplev calibration (BS? PRM?)

• Sensing matrix
• Cavity length (use new Anamaria method)
• Loop gain (make sure loop is stable for measurements)
• Noise budget
• Full Finesse model.
• Fix hardware anti-aliasing in LSC (move up cutoff freq to correspond to sample rate)

DRMI

This and FPMI are the next primary tasks. We will need to vent to flip SR2 first, although we need better calculation of the PRC/SRC coupled-cavity affect on the SRC mode.

• SRC mirror RoC calculations. What is the long-term solution? (Jamie)

End table upgrade

This is needed before we move on the FPMI commissioning.

• Project page

• ETMY table must be completed ASAP (Manasa)
  • What is left to do?
• ETMX upgrade needs to be planned/coordinated.

FPMI

We obviously need both end tables fully functional before we get to this.

PRFPMI

• Oplev calibration for ETMX, ETMY

DRFPMI

Next vent

Will need to vent soon to flip SR2.

• SR2 flip
• Are all black glass beam dumps installed?

Longer term:

• New OSEM mount screws
• New periscope plate