To K. Yamamoto-san, M. Yamamoto-kun, Sato-kun

We confirmed that the beacon signal from the drumhead mode of ETMX could be seen in the CARM signal. Therefore, the beacon signal is larger than the frequency noise so that we can measure the Q-value of ETMX drumhead mode with X-arm.

### What we did

• After the FPMI lock, I send the 23.69 kHz beacon signal from Moku:Lab nearby the OMC rack to ETMX. And I confirmed the beacon signal could be seen in the DARM signal as before.
• According to Michael-san's klog, now, MokuIOOrack input ports are connected to TEST ports in the Common path of CARM Common Mode Servo.
• I connected MokuIOOrack and measured the spectra of the CARM signal to check whether there was a peak of the beacon in the CARM signal, and I found it (Fig.1).
• Therefore, the beacon signal is larger than the frequency noise so that we can measure the Q-value of ETMX drumhead mode with X-arm.