After the calibration parameter updates, we confirmed only changes are foton filters for optical gain and actuator efficiencies (Fig.1) and SDF tables (Fig.2-3) for pcal beam position (klog#34095) and line tracking (klog#34096) parameters.
There is no update in guardians (Fig.4) and models (Fig.5), so we skipped the check with lockloss-relock cycles by guardian. After then, we raised CFC_LATCH in order to move from CALIB_NOT_READY to READY.
Following differences were accepted (Fig.1) related calibration updates and were reverted (Fig.2) for removing numerical error issue.
Please find them in JGW-L2314962. They are the parameters for tracking calibration lines with latest calibration parameters in klog#34090.
Pcal SFDs were accepted.
Related report: klog34094
CAL group
We did the calibration measurements and haven't found strange results.
Estimated parameters in the Pre-maintenance measurements are as follows.
H_etmxtm = 3.87175e-14 @10Hz ( -0.1% from previous measurements)
H_etmxim = 1.55407e-14 @10Hz ( -5.5% from previous measurements)
Optical_gain = 2.187716e12 ( -0.5% from previous measurements)
Cavity_pole = 17.99656 Hz ( -0.4% from previous measurements)
Previous values are listed in klog#34048.
Fig1. shows the fitting results of pre measurements.
Estimated parameters in the Post-maintenance measurements are as follows.
H_etmxtm = 3.878432e-14 @10Hz ( 0.17% from pre-maintenance measurements)
H_etmxim = 1.589672e-14 @10Hz ( 2.3% from pre-maintenance measurements)
Optical_gain = 2.191044e12 ( 0.15% from pre-maintenance measurements)
Cavity_pole = 18.04787 Hz ( 0.28% from pre-maintenance measurements)
Fig2. shows the fitting results of post measurements.
After the calibration parameter updates, we confirmed only changes are foton filters for optical gain and actuator efficiencies (Fig.1) and SDF tables (Fig.2-3) for pcal beam position (klog#34095) and line tracking (klog#34096) parameters.
There is no update in guardians (Fig.4) and models (Fig.5), so we skipped the check with lockloss-relock cycles by guardian. After then, we raised CFC_LATCH in order to move from CALIB_NOT_READY to READY.
Here is a update of the 7 blasting between 2025/05/30 18:10:00 UTC and 2025/06/05 13:26:35 UTC.
Note that sometimes the reported time and blasting execution time are different. In maximum, the blasting happened 4 minutes earlier than the reported time.
A CAL Tcam session was performed to obtain beam position information necessary for Pcal. The parameters have already been updated, and SDF is expected to be accepted.
Operator: Dan Chen
Update Time: 2025/06/06 16:14:20
EPICS Key | Before [mm] | After [mm] | Δ (After - Before) [mm] |
---|---|---|---|
K1:CAL-PCAL_EX_TCAM_PATH1_X | 2.39397 mm | 2.61720 mm | +0.22323 mm |
K1:CAL-PCAL_EX_TCAM_PATH1_Y | 62.83238 mm | 62.33808 mm | -0.49430 mm |
K1:CAL-PCAL_EX_TCAM_PATH2_X | -0.77319 mm | -0.54384 mm | +0.22935 mm |
K1:CAL-PCAL_EX_TCAM_PATH2_Y | -64.56790 mm | -65.08563 mm | -0.51773 mm |
Update Time: 2025/06/06 16:16:04
EPICS Key | Before [mm] | After [mm] | Δ (After - Before) [mm] |
---|---|---|---|
K1:CAL-PCAL_EX_TCAM_MAIN_X | 3.85852 mm | 3.62544 mm | -0.23307 mm |
K1:CAL-PCAL_EX_TCAM_MAIN_Y | 10.68901 mm | 10.71490 mm | +0.02588 mm |
Update Time: 2025/06/06 16:17:08
EPICS Key | Before [mm] | After [mm] | Δ (After - Before) [mm] |
---|---|---|---|
K1:CAL-PCAL_EY_TCAM_PATH1_X | -0.07254 mm | -0.37174 mm | -0.29920 mm |
K1:CAL-PCAL_EY_TCAM_PATH1_Y | 61.06124 mm | 60.86531 mm | -0.19593 mm |
K1:CAL-PCAL_EY_TCAM_PATH2_X | -0.05695 mm | -0.33094 mm | -0.27399 mm |
K1:CAL-PCAL_EY_TCAM_PATH2_Y | -70.29661 mm | -70.46008 mm | -0.16347 mm |
Update Time: 2025/06/06 16:18:02
EPICS Key | Before [mm] | After [mm] | Δ (After - Before) [mm] |
---|---|---|---|
K1:CAL-PCAL_EY_TCAM_MAIN_X | 5.06633 mm | 6.12295 mm | +1.05662 mm |
K1:CAL-PCAL_EY_TCAM_MAIN_Y | -3.20391 mm | -3.00409 mm | +0.19982 mm |
[Kimura]
Technical staff reported that the air compressor next to the IXC (see attached photo) is in operating condition.
Since the temperature around the IXC will change if it is stopped, we discussed the matter with Ushiba-san and decided to leave it as it is until next week.
 We need to discuss about stopping the air compressor early next week.
I performed the lockloss investigation for the recent lockloss from the OBSERVATION state of the LSC_LOCK guardian, between 2025-06-05 01:22:05.687500 UTC and 2025-06-06 01:49:44.812500 UTC. The previous lockloss investigation was posted in klog34073. During this period, there were 10 lockloss from the OBSERVATION state. The plots are listed in DAC wiki.
For 4 lockloss, we saw the excess of the seismic motion with 1~10 Hz, which made the oscillation of the IMC length control and caused the IMC lockloss.
For 1 lockloss, we saw the excess of OMC DCPD (K1:OMC-TRANS_DC_SUM_OUT_DQ and K1:OMC-TRANS_DC_{A, B}_IN1_DQ) from -10 s, as shown in Figure 1. We are not sure the origin of this excess.
Separately, Figure 2 shows the excess of OMMT2 TRANS at -23, 19, and -5 s. These excess has a coincidence with the transient behavior of K1:VIS-ETMY_MN_OPLEV_TILT_SUM_OUT_DQ.
Note that this will not be related to the lockloss.
Figure 3 shows the oplev sum of ITMY and ETMY over a four hours. Sometimes we can see the transient behavior in the oplev sum of ETMY MN. It has a coincidence with the OMMT2 TRANS, as shown in Figure 4. And also, we can see the transient shift of the oplev sum of ITMY MN. As I heard from Yokozawa-san, this seems to be a mode hop.
The duty cycle of June 5 was 71 %.
[Shih-Hong, Yuzurihara]
As a continuous analysis of klog34029, we checked the Gauch page and found the MICH channel shows the non-Gaussian behavior in 10~20 Hz. Figure 1 shows an example of the Gauch. This phenomenon began on 6/2 at 14:00 UTC (Gauch).
Figures 2~4 show today's sensitivity and noise projection from MICH. The spectral shape of the sensitivity around 15 Hz is similar to the MICH shape.
In the summary page, you can see the time variation of the MICH spectrum. (This shoulder-ish shape looks like the scattered light noise.)
Figure 5 shows the Q-spectrogram (by Pastavi) of the MICH error signal. This noise is a scattered light noise. By rough eye check, the frequency of the scattered object seems to be 0.2 Hz. (= ~12 period/60 s)
Yokozawa-san will report his continuous analysis.
[YamaT-san, Miyakawa-san, Ikeda]
Since the TIM and ADC error lights were on for the following model, We performed a DiagReset.
We performed the reset with the intention of confirming whether the issue recurs during future observations.
13:39 DiagReset
Error
k1iopmcf0 TIM, ADC
k1pemmcf0 TIM
k1iopiy0 TIM, ADC
k1pemiy0 TIM
k1ioppx1 TIM, ADC
[YamaT-san, Ikeda]
This is work related to K-Log#33393.
We have replaced the HDD on Disk9 Pod1.
Disk6 Pod1 will not be replaced now.
If the number of errors increases, it will be replaced.
The fowlloing paramters were updated based on the CAL Tcam session reported klog34078.
Pcal Tcam sesion was performed before today's maintenance works.
Beam position information channels were updated and the SDF was accepted.
We plan to update them again after maintenance works.
[Kimura and Yasui]
We turned on #33, #37, #39, and #31 ion pumps in EX area.
After the ion pumps were turned on, the GV between the T-pipe and TMP was closed except for the #39 TMP.
#39 TMP has an interlock circuit (K-log 33547) and the pump unit is pumped in parallel with the TMP and ion pump.
CAL lines in high frequency for the cross-check purpose doesn't seem to be enabled.
Attachment shows the comparison plots at calibration lines between DARM and witnesses below 100Hz (Fig.1) and above 100Hz (Fig.2).
Essential calibration lines shown below are enabled. So line tracking can be done in minimum.
- EXTM: 27.650Hz for actuator efficiency
- Px1: 28.670Hz for actuator efficiency
- Px2: 31.530Hz for optical gain and cavity pole
- Px3: 507.890Hz for optical gain and cavity pole
And also, a line for the cross-check between Pcal-X and Pcal-Y are also enabled.
- Py1: 32.790Hz for cross-check between Pcal-X and Pcal-Y
On the other hand, lines for checking HF doesn't seem to be enabled. Roughly 1-2hrs integration to see them on DARM. So it's difficult to see on the quick check. But now they are not seen also on RxPD. We need to consider permissions (is this change acceptable), procedures (how to enable them), and a schedule (when they can be enabled), etc.
- Px4: 2002.010Hz
- Px5: 2998.730Hz
I performed the lockloss investigation for the recent lockloss from the OBSERVATION state of the LSC_LOCK guardian, between 2025-06-04 06:24:36.937500 UTC and 2025-06-05 00:44:39.437500 UTC. The previous lockloss investigation was posted in klog34054. During this period, there were 6 lockloss from the OBSERVATION state. The plots are listed in DAC wiki.
For 2 lockloss, we saw the excess of the seismic motion with 1~10 Hz, which made the oscillation of the IMC length control and caused the IMC lockloss.
From my experience, their cause seems to be blasting. I will wait for the report on the actual blasting execution time.
Thanks to the modification of the BPC for ETMY pitch (klog34016) on June 2, the lock duration is now longer and more stable. I focused on the drift of the alignment control, such as ASC or BPC.
Figure 1 shows the BPC error and feedback signals. It takes 2 hours to reach an equilibrium of BPC for PRM YAW. It takes 30 minutes to reach an equilibrium of BPC for ITMX YAW. Figure 2 shows the oplev signals. The amount of shifting the PRM seems ~2 urad.
Except for this, I didn't see a significant drift of the alignment control (ASC and BPC).
Figure 3 shows the oscillation of IR trans and DHARD_P at -1 min. Coincidentally, we can see the excess of OMMT2 TRANS. This oscillation can be seen in other ASC and BPC (Figures 4 and 5).
Figure 6 shows the duty cycle on June 3 and June 4. They were 76% and 71%, respectively.