Betsy, Travis, Giles

Good progress had been made on successfully welding 2 of 4 fibers to the ETMx and it's PUM this morning.  However, upon completion of the 5th weld we noticed a small feature had appeared behind the top left corner of one of the prisms on the PUM.  While observing the feature for another 10 minutes, the feature grew and became an obvious fracture in the glass mass.  The fracture started while we were welding in close proximity to the prism.  Once we noticed the feature we stopped welding.  Note, the prism takes a compressive load when the QUAD is fully suspended, so it is not yet obvious that we should or should not continue to use this mass.  We have been in contact with SYS, in an attempt to catch COC before COB today - we plan to talk in the morning with a wider audience about what to do next.

Pictures of the fracture are on Resource Space in a collection with:

https://ligoimages.mit.edu/?r=25246