Participants : Y. Aso, M. Eisenmann, M. Otsuka, S. Singh, K. Yamamoto

 * New ITMs preparation : 
small cracks removed by Oktamoto and accepted by Nikon
polishing started at Nikon and should last 1 year (up to ~Sept/Nov 2025) ; should have a more realistic schedule in the coming week to then discuss with LMA
birefringence and Q measurements before/after coating if time allows 

 * Coating at U. Toyama : 
will restart measurement soon :
TAMA coating on sapphire disk with better temperature resolution
waiting GeO2 recipe of LMA which is delayed du to O4 delay
maybe blistering solved and better performances at cryo temperature ? 

 * Sapphire spectroscopy at NAOJ : 
got iLM/LMA sample and waiting for instrument availability to start measurement with s-polarized light

 * birefringence measurements at NAOJ : 
final checks for 1D measurements and preparation of 2D measurements

 * Parametric Instabilities :
now doing mechanical simulation to reproduce Kaihotsu-san result 
At cryogenic temperature there is a discrepancy of C14 parameter between litterature and thesis..
However, Kaihotsu-san simulation was confirmed with room temperature measurement
Maybe more information in Yukino Mori thesis with value measured on sapphire disk