Reports until 14:55, Thursday 20 February 2025
H1 ISC
matthewrichard.todd@LIGO.ORG - posted 14:55, Thursday 20 February 2025 - last comment - 15:55, Thursday 20 February 2025(82942)
POP AIR path power measurements

Matthew Mayank Sheila

We went out to ISCT1 to measure the power coming to the POP AIR port, components are labeled in Sheila's alog. It seems the 50/50 beamsplitter is acting appropriately.

2025-02-20 10:28:11.348428 PST:
  H1:ASC-POP_X_DC_NSUM_OUT16 = 1.1193946024467205
  H1:LSC-POP_A_LP_OUT16 = 39.499373468859446

BS9010 power: 3.6 mW
POPX power: 1.8 mW

2025-02-20 10:35:24.229534 PST
  H1:ASC-POP_X_DC_NSUM_OUT16 = 1.1307608842849726
  H1:LSC-POP_A_LP_OUT16 = 39.88992869059245

These average power measurements were taken using

cdsutils avg +30 H1:ASC-POP_X_DC_NSUM_OUT16 H1:LSC-POP_A_LP_OUT16
Comments related to this report
sheila.dwyer@LIGO.ORG - 15:55, Thursday 20 February 2025 (82946)
Link

The large beam size coming off the periscope meant it was difficult to use the power meter until downstream of the lens.  That's why the first measurement was directly after the 90/10 BS.