Minutes of the ISC meeting on 2015/8/24

2015/8/24 14:00 - 15:00

SeeVogh + Kamioka TV conference room

Participants: Nagano, H. Yamoto, Kokeyama, Hirose, Ueda, Aso, Somiya, Arai



Deadline for deciding the spec. for IBF

Simulation Scope

Optics data used for simulation

  1. Test mass surface maps : Information available are the Zygo pathfinder result and the CSIRO coating on Sapphire. Based on these + educated guess + aLIGO silica mirror maps (~30), make up enough maps to understand the uncertainty.
  2. ITM transmission maps : Use data of existing 1 pathfinder sapphire substrate. These maps will be with and without power term subtracted, to see the benefit of IBP.
  3. BS : full set available
  4. RC mirrors : use polished surface data. No mirror map available after the coating.

What are to be calculated - with and without thermal heating of BS and RC masses

  1. PRG and contrast defect of CR and SB
  2. Gouy phase in PRC and SRC
  3. mode matching of PRC and SRC
  4. DC sensing signal related to ASC (RF WFS signals at very low frequency)
  5. DC readout signal
  6. Cross check with Finesse

Thermal deformation of BS is calculated using COSOL, and the Hello-Vinet formula is used for RC mirrors.

The mode matching calculation will be done

  1. calculate the idealistic modes without including mirror aberrations
  2. calculate the mode matching at the cold state using maps
  3. calculate the mode matching as a function of heating with maps and thermal deformation.

Mode matching is quantified by comparing how much the stationary modes deviate from the idealistic modes on AR side of PRM, SRM and ITMX/ITMY.

Requirements of RoC of mirrors is not the scope of this analysis, i.e., all RoCs in the simulation are those in the KAGRA MIF webpage.

Output Optics

OMC Layout Plan: OMClayout3.pdf

Next meeting

2015/9/7(mon) 14:00 -15:00

KAGRA/subgroup/ifo/MIF/Minutes20150824 (last edited 2015-09-02 07:06:43 by YoichiAso)