I finished the replacement of the Pastavi server at Kashiwa (in computer room of daini sougou tou). Now the new server is working well for the Pastavi.
From the user side, the usage is same as previous. The way to access the server is written in the document.
I tested most of the options in several modes including the noise budget mode. As I checked, the options is available on the new environment.
If you faced any issue, please share the information with me.
The remained task is to develop the new scheme to handle several job by using HTCondor.
Date: 2026/03/19
Member: Dan Chen, Shingo Hido, Misato Onishi
We performed our usual WSK calibration at UToyama.
The results look no problem.
| Case | Alpha (Main Value) | Alpha (Uncertainty) |
| Front WSK, Back GSK | -0.910663 | 0.000331 |
| Front GSK, Back WSK | -0.911063 | 0.000076 |
Comparing with previous results, no significant issues were found.
Attached graph is the result summary including the latest measured data.
[Kimura and M. Takahasi]
On March 18, we switched form TMP to the Ion pump of the #36 vacuum pump unit at the Y-end .
After the activation of the #36 Ion pump, we turned off the #36 TMP and dry pump
[Kimura and M. Takahashi]
On March 18, we completed maintenance work on the duct-shield cryo-coolers for the EYC.
We are planning to restart the duct-shield cryo-coolers starting March 23, which will also serve as a test run.
[Kimura and M. Takahashi]
As part of maintenance work on the cryogenic cooling units, we removed two valve units from the radiation shield cryo-coolers (P-53 and P-55) of EYC.
The removed valve units were packaged and returned to the manufacturing plant, where they will be disassembled and inspected.
We plan to remove the remaining valve units from the IXC, IYC, and EXC radiation shield cryo-coolers early next week.
Workers: Kohei Mitsuhashi, Dan Chen
We performed monthly Pcal-X calibration on 2026/03/18.
After the calibration, we updated EPICS parameters related to the Pcal-X system. No issues were found.
| EPICS Key | Before | After | Δ (After − Before) |
|---|---|---|---|
| K1:CAL-PCAL_EX_1_OE_R_SET | 0.98489 | 0.98417 | -0.00072 |
| K1:CAL-PCAL_EX_1_OE_T_SET | 0.98489 | 0.98417 | -0.00072 |
| K1:CAL-PCAL_EX_1_PD_BG_RX_V_SET | -0.00381 | -0.00386 | -0.00005 |
| K1:CAL-PCAL_EX_1_PD_BG_TX_V_SET | 0.00689 | 0.00602 | -0.00087 |
| K1:CAL-PCAL_EX_1_RX_V_R_SET | 0.50206 | 0.50202 | -0.00004 |
| K1:CAL-PCAL_EX_2_INJ_V_GAIN | 0.95148 | 0.95101 | -0.00047 |
| K1:CAL-PCAL_EX_2_OE_R_SET | 0.97457 | 0.97404 | -0.00053 |
| K1:CAL-PCAL_EX_2_OE_T_SET | 0.97457 | 0.97404 | -0.00053 |
| K1:CAL-PCAL_EX_2_PD_BG_TX_V_SET | 0.00551 | 0.00519 | -0.00032 |
| K1:CAL-PCAL_EX_2_RX_V_R_SET | 0.49794 | 0.49798 | 0.00004 |
| K1:CAL-PCAL_EX_WSK_PER_RX_SET | 1.48800 | 1.48915 | 0.00115 |
| K1:CAL-PCAL_EX_WSK_PER_TX1_SET | 0.52710 | 0.52744 | 0.00035 |
| K1:CAL-PCAL_EX_WSK_PER_TX2_SET | 0.38759 | 0.38799 | 0.00040 |
I offloaded the F0 and F1 GAS filters with the FRs.
[Kimura and Yasui]
Parts replaced during maintenance work
1. Absorber in the helium compressor
2. Filter unit at the supply side
3. Gas replacement inside the cold head in accordance with SHI work procedures
4. Disassembly and maintenance of the valve unit at the SHI factory
5. Gas replacement in the compressor and flexible tubing
(1) Helium gas used: G-1 grade
(2) Filling pressure: 14.8 bar
A CAL Tcam session was performed to obtain beam position information necessary for Pcal. The parameters have already been updated, and SDF has been accepted.
Operator: Shingo Hido, Kohei Mitsuhashi, Dan Chen
Update Time: 2026/03/18 07:41:38
| EPICS Key | Before [mm] | After [mm] | Δ (After - Before) [mm] |
|---|---|---|---|
| K1:CAL-PCAL_EX_TCAM_PATH1_X | 0.07325 mm | -0.87474 mm | -0.94799 mm |
| K1:CAL-PCAL_EX_TCAM_PATH1_Y | 66.15693 mm | 66.37439 mm | +0.21746 mm |
| K1:CAL-PCAL_EX_TCAM_PATH2_X | 0.56752 mm | -0.37755 mm | -0.94507 mm |
| K1:CAL-PCAL_EX_TCAM_PATH2_Y | -68.50339 mm | -67.02710 mm | +1.47629 mm |
This work is continued from klog36589
## GAS control modification
According to yesterday's results related to GAS, there seem to be gain peaking at 3-4 Hz. So I reduced {F0,F1,BF} gains to -6dB. After that I measured their OLTFs when SR2 is in the LOCK_ACQUISITION state. Fig.1,2,3 show the results. Unfortunately, OLTF could not be measured well maybe due to the coupling between GAS controls. Acoording to loop suppression (IN2/EXC), their controls seem to work well and the peaking around 3-4Hz becomes smaller. Fig.4 shows the error/feedback spectra. The peaking seems to be disappeared although each residual GAS motion seems to be not changed so much.
## IM DAMP roll off modification
I also modified the roll off filters for IM DAMP {L, P, R, Y}. As for T and V, elliptic filter was also not used in SR3. So I did not touch them in this time. (Maybe it is better to change)
I measured the OLTFs after the modification. Figure.5, 6, 7, and 8 show the OLTFs of IM DAMP {L,P,R,Y}. Also Fig. 9 and 10 show the error/feedback spectra. the feedback above 10 Hz was rolled off successfully.
[Kimura and Yasui]
At around 10:00 a.m. on March 17, we stopped the vacuum pumping in the Q-mass piping, opened the cryostat-side GV, and connected the Q-mass.
The pressure inside the piping before opening the cryostat-side GV was 1.8×10⁻⁴ Pa, and after opening the GV, it was 4.4×10⁻⁵ Pa.
We then installed an analysis unit on the Q-mass piping. The final pressure inside the piping was 3.5 × 10⁻⁵ Pa.
We then removed the vacuum pumping unit from the piping.
[Kimura and Yasui]
On March 17, we completed maintenance work on the duct-shield cryo-coolers for IXC and IYC.
Maintenance work on the duct-shield cryo-coolers for EXC and EYC is also scheduled to be completed by the end of this week.
We are planning to restart the duct-shield cryo-coolers starting March 23, which will also serve as a test run.
[Kimura and Yasui]
Parts replaced during maintenance work
1. Absorber in the helium compressor
2. Filter unit at the supply side
3. Gas replacement inside the cold head in accordance with SHI work procedures
4. Disassembly and maintenance of the valve unit at the SHI factory
5. Gas replacement in the compressor and flexible tubing
(1) Helium gas used: G-1 grade
(2) Filling pressure: 14.8 bar
[Kimura and M. Takahashi]
On March 18, we completed maintenance work on the duct-shield cryo-coolers for the EYC.
We are planning to restart the duct-shield cryo-coolers starting March 23, which will also serve as a test run.
We performed monthly Pcal-Y calibration on 2026/03/17.
After the calibration, we updated EPICS parameters related to the Pcal-Y system. No issues were found.
| EPICS Key | Before | After | Δ (After − Before) |
|---|---|---|---|
| K1:CAL-PCAL_EY_1_OE_R_SET | 0.98973 | 0.98977 | 0.00004 |
| K1:CAL-PCAL_EY_1_OE_T_SET | 0.98973 | 0.98977 | 0.00004 |
| K1:CAL-PCAL_EY_1_PD_BG_RX_V_SET | -0.00484 | -0.00492 | -0.00008 |
| K1:CAL-PCAL_EY_1_PD_BG_TX_V_SET | 0.02704 | 0.01218 | -0.01486 |
| K1:CAL-PCAL_EY_1_RX_V_R_SET | 0.50319 | 0.50276 | -0.00044 |
| K1:CAL-PCAL_EY_2_INJ_V_GAIN | 0.51512 | 0.51836 | 0.00324 |
| K1:CAL-PCAL_EY_2_OE_R_SET | 0.98618 | 0.98609 | -0.00009 |
| K1:CAL-PCAL_EY_2_OE_T_SET | 0.98618 | 0.98609 | -0.00009 |
| K1:CAL-PCAL_EY_2_PD_BG_TX_V_SET | 0.02955 | 0.01466 | -0.01489 |
| K1:CAL-PCAL_EY_2_RX_V_R_SET | 0.49681 | 0.49724 | 0.00044 |
| K1:CAL-PCAL_EY_WSK_PER_RX_SET | 1.84214 | 1.84228 | 0.00015 |
| K1:CAL-PCAL_EY_WSK_PER_TX1_SET | 0.33376 | 0.33354 | -0.00023 |
| K1:CAL-PCAL_EY_WSK_PER_TX2_SET | 0.90500 | 0.90266 | -0.00234 |
A CAL Tcam session was performed to obtain beam position information necessary for Pcal. The parameters have already been updated, and SDF has been accepted.
Operator: Kohei Mitsuhashi, Dan Chen
Update Time: 2026/03/17 15:31:24
| EPICS Key | Before [mm] | After [mm] | Δ (After - Before) [mm] |
|---|---|---|---|
| K1:CAL-PCAL_EY_TCAM_PATH1_X | 1.33223 mm | 0.76950 mm | -0.56273 mm |
| K1:CAL-PCAL_EY_TCAM_PATH1_Y | 65.85923 mm | 65.80570 mm | -0.05353 mm |
| K1:CAL-PCAL_EY_TCAM_PATH2_X | -0.29757 mm | 1.39102 mm | +1.68859 mm |
| K1:CAL-PCAL_EY_TCAM_PATH2_Y | -69.75503 mm | -69.21742 mm | +0.53761 mm |
I offloaded the F2 and BF GAS filters with the FRs.
[Washimi, Takahashi]
We replaced the broken signal generator (SG) NF1956 with the embedded SG card for the LVDT driver (S1807787) in TMSX. We opened the driver chassis and inserted the SG card. The output of the SG card was connected to "REF IN" port on the front panel. The signal was set to 10kHz in frequency and 7Vp-p in amplitude.