KAGRA Logbook

Reports 1-1 of 1

MIR (EX)

kenta.tanaka - 18:42 Tuesday 04 February 2025 (32584)

Current ETMX drumhead mode frequency is 23.663 kHz

I scanned the elastic mode of ETMX TM to search the drumhead mode frequency for OMC ASC with beacon.

I found that the EX drumhead mode frequency seems to be 23.664 kHz when IM temperature is 87K (fig.1).

Also I found the other 2 small peaks are at 23.847 kHz and 23.973kHz.

Moreover, I found that the current MIR PDs seems not to be sensitive (unplugged?). According to the previous log, the PD cannot be seen the peak since last July.

Images attached to this report

32584_1738662148_Screenshot from 2025-02-04 18-41-10.png

Comments to this report:

satoru.takano - 6:23 Thursday 06 February 2025 (32598)

If my memory is correct, we checked that PD after the measurement and confimed that at least the cables were connected to the SR560 and the AA chassis. We didn't check the signals one by one, so something between the PD and the CDS may have not worked well.