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= Thermal compensation system for the 40m arm cavity = = Tuning Fabry-Perot cavity modal frequencies using a thermal phase error correction feedback system =
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 1. What are the ideal cavity parameters? (a reference to compare the different corrections brought about by heating the mirror)  1. What are the ideal cavity parameters? (a reference to compare the different heating models)
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 3. Increase or decrease RoC of the ETM to correct for inhomogeneities  3. Increase or decrease RoC of the ETM to correct for inhomogeneities (choose between the ring-heater design and the VIRGO chrocc design)
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 4. Desired tuneable range and acheivable range  4. Desired tuneable range and achievable range
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 5. Best heating profile  5. Effect of heating at 1064nm and 532nm
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 6. Practical/hardware limitations in implementing  6. Best heating profile

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. Practical/hardware limitations in implementing

Tuning Fabry-Perot cavity modal frequencies using a thermal phase error correction feedback system

Goal

To compensate for imperfections that arise due to optical inhomogeneities in the arm cavity mirrors by designing and implementing a thermal compensation system.

The lessons learned from this exercise will help in designing/implementing a similar kind of system for the folding mirrors in the recycling cavities.

Fact-finding

  1. What are the ideal cavity parameters? (a reference to compare the different heating models)
  2. Sources of inhomogeneity : (i) Deviation from mirror specs (ii) Thermal effects due to circulating arm cavity power (iii) Surface roughness
  3. Increase or decrease RoC of the ETM to correct for inhomogeneities (choose between the ring-heater design and the VIRGO chrocc design)
  4. Desired tuneable range and achievable range
  5. Effect of heating at 1064nm and 532nm
  6. Best heating profile
  7. Practical/hardware limitations in implementing

Modelling using SIS/COMSOL

Advanced_Techniques/Adaptive_Thermal_Compensation (last edited 2013-11-16 13:50:04 by ManasadevithirugnanasambandamATligoDOTorg)