[Shalika, Mitsuhashi-san]

This elog is about doing the ringdown measurement. In continuation to work in elog. 

Details:

1. The amplitude of TEM00 mode in transmitted signal is 37mV. The PD at transmitted beam is set with 20dB attenuator. The cavity was able to lock the TEM00 mode at 37mV for 12 minutes. The error signal(CH1--yellow) for the corresponding peak looks as shown in Fig 1. The demodulation phase was set to 185º.

2. The filter cut off frequency was 3 Hz and gain was 100. 

3. The laser temperature was 8510±20. The offset voltage varied from -0.1 to 0.1. 

4. The feedback signal(CH4--green) and error signal(CH1--yellow) during lock looks as in Fig 2.

5. The ringdown measurement was done by setting the trigger and switching off AOM. The signals look as shown in Fig 3,4,5. 

Next Step:

We will analyze the data to calculate the decay time.