We started at 14:00 UTC and to not interfere with the ITF and risk to unlock, we manually injected the SQZ.
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System initial status: ITF LOW NOISE 3; SQZ_MAIN @SQZ_Locked_NO_FC
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14:28:26 AA loop engaged
We performed a first CC phase scan (Fig. 1-2):
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14:39 CC scan started DCP = 195 Hz
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15:02:21 CC scan ended (fast shutter closed), ITF in shot
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15:26:15 fast shutter opened
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15:36:22 ITF in SQZ phi0 = 0.65 rad
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15:39:19 SQB1 TX angle set to 300 (initially at 310)
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16:42:58 SQB1 X position set to -3200 (original position)
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16:47:58 ITF in SQZ
After the first CC scan we realized the magnitude was similar to the last shift (entry #64094) even though there should be a higher level of injected SQZ. We decided to try to improve the magnitude by acting on SQB1_TX and SQB1_X DOFs. We worked on this from 15:39:19 to 16:42:58 UTC. Finally we left SQB1_X as it was and we changed the set point of SQB1_TX from 310 to 330 urad. The fluctuations on the magnitude are reduced (Fig. 3).
We then performed another phase scan (Fig. 4-5)
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17:05 CC scan started DCP = 195 Hz
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17:28 CC scan ended (fast shutter closed), ITF in shot
After the second CC scan we realized the SQZ angle is actually around 1.05 rad, so we decided to repeat the SQZ mode acquisition.
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17:39:53 fast shutter opened, ITF in SQZ phi0 = 1.05 rad
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17:49:08 CC loop engaged, gain=75000 (glitch between 17:54:50 and 17:56:14)
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17:58:54 ITF in ASQZ phi0 = 2.75 rad
We were able to get another CC phase scan with DCP setpoint at 225 Hz (Fig. 6-7). Fig. 8 reports also the shot SQZ and ASQZ acquisitions made after the scan.
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18:11 DCP value set to 225 Hz
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18:44:11 ITF in shot
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18:46: CC scan started DCP = 225 Hz
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19:09 CC scan ended
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19:15:07 ITF in ASQZ phi0 = 2.7 rad
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19:22:48 ITF in SQZ phi0 = 0.95 rad
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19:28 DCP value set back to 195 Hz