Shifter: Matthew Ball

Fellow: Sudarshan Karki

Mentor: Borja Sorazu

• Mean duty cycle: 46.6% + 52.9% + 83.7% + 58.7% + 76.3% + 92.7% + 99.7% = 72.9%
• Several sudden locklosses where operators noted coincident FSS transients
• ITMX temperature jumped (back) up on Tuesday, recovering from a drop on January 21
  • ITMY also dropped on Jan 21, but has not recovered yet
• 33Hz on/off line noted in previous DQ shifts lines up with many corner station accelerometers
  • A Bruco scan of one of the flare-ups found coherence with a HAM 6 accelerometer and the M2 level of the beam splitter suspension
• A 90Hz glitch line shows up sporadically through the week
• Heavy wind during the latter half of the week led to several drops in range and (at least) one lockloss
• Squeezer issues plagued Saturday and Sunday:
  • It "stalled" several times, knocking the IFO out of observing
  • Elevated DCPD signal lines up with significant range drops. This behavior is usually near one of these "stalls"
• On the plus side, varying the CLF demod angle bumped the range up to 120Mpc on Friday

Full shift: https://wiki.ligo.org/DetChar/DataQuality/DQShiftLHO20200127