1.) Behind on schedule for data analysis (and writing) by 2 weeks

• Finally got the code again working late last week so analysis of the next 5 tests should go fast
• crack velocities peak at 1200 m/s, and mostly reside in the 100’s of m/s
• force sensor seems to have an inherent response time of ~5 µs
• force curves seem to have a second plateau after load drop
  • need to check if this is an artifact from the force sensor or genuinely linked to some fracture phenomena where the crack arrests temporarily

2.) Need to think harder about converting reaction force readout to stress intensity factor at the notch tip and comparing time till K=K_1c to time of failure. How far do I go down the road of quartz specific analysis as opposed to design of apparatus focus?

3.) Rough draft of introduction is nearing submission for first edit. All other sections are largely contingent on data analysis although introduction is mildly contingent on answer to #2.

• Working on Characterizing Piezo Actuator
  • Measured velocity with the PDV system
    • tentative peak velocity with an input signal rise time of 5 µs: 0.51 m/s
    • tentative peak velocity with an input signal rise time of 10 µs: 0.35 m/s
  • Working on building a voltage divider circuit
    • Had to go buy 25W resistors and a larger enclosure from an electronics store (the small 2W resistors smoke and ignite)
• Accepted the LLNL job offer, start August 29th
  • Should be a lot of work at DCS