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MIF (General)

masahide.tamaki - 7:39 Friday 23 December 2022 (23335)

strage shape in MICH displacement line

Tanaka, Tamaki

During TF measurement (klog23334), there were strage shape in MICH displacement (Fig1) even FPMI lock wasn't lost.
When this happened I was not injecting the excitation to anywhere.

We checked MICH error signal and feedback signal (K1:LSC-MICH1_IN1, K1:LSC-MICH2_OUT), and POP PD signal (POP_PDA1_RF17_Q_{ERR_DQ, NORM}), but we did not find anything suspicious.

These events occurred several times during about 30 minutes around 01:00 on 12/23 (JST), but have not occurred since then.

Images attached to this report

23335_1671747490_Screenshot from 2022-12-23 01-02-40.png

Comments to this report:

takahiro.yamamoto - 19:20 Friday 23 December 2022 (23354)

As shown in Fig.1, bit-error like signals can be seen in the calibrated MICH on k1calcs and in feedback signal on k1bsp.
Because we cannot see such signals in feedback signal on k1lsc, these events seem to come from IPC network.
(IPC connections are constructed as shared memory for k1lsc=>k1calcs and the Dolphin for k1lsc=>k1bsp.)

We probably need to reduce a CPU load of k1lsc.

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