SN1009 (80 mm witness sample) was annealed between 25 and 26 January 2022 - used the large furnace in Downs 221, atmosphere was air, used glass petri dishes to protect optic (from Gabriele and CRiMe). Start time was 17:48 Pacific, and sample was removed at ~17:30 Pacific on the next day.

Controller parameters:

Ramp up rate = 100 °C per hour
Hold temp = 400 °C
Hold time = 10 hours
Ramp down rate = 100 °C per hour

Additional annealing run after ENG_Labs/260 at higher temperature to hopefully yield improvements to absorption.

Witness RTD observed a 421.1 °C overshoot and 14.5 °C offset from controller RTD. These parameters were consistent with the elog entries ENG_Labs/253, ENG_Labs/254, and ENG_Labs/260. See attached image of the temperature profile (.xlsx file is source document).

Optic is now with Liyuan in RTS for recharacterization after anneal.