We made new script to input water flow meter values into EPICS channel.
/kagra/bin/SYS/water.sh
This script is processed by cron on k1script1 by 5 minutes.
During last night, a beam dump shut out also the return light to PSL room.
So a PD at PSL room received just only the output light of Prometheus.
Akutsu-san put the beam dump around -17h in Fig.1.
Then, the fluctuation in readout value of the PD for X disappeared.
Fringe amplitude may be affected by fiber coupling at PSL.
By the way, I found K1:ALS-?_FIB_SERVO_.* was set up farther downstream than I had expected.
A figure in Mirror map became slightly old.
JGW-D1808971 is newer than Mirror map. But I heard it was not also the latest layout.
With Hirata-san and Yano-san.
Pictures can be found in the album SR2 Remedying work after O3.
Yesterday we inspected the mirror with the super ultra high intensity LED lamp. It was very hard to take pictures but Hirata-san made a video.
There are two spots of dirt at the HR side. They are not so close to the centre. Namely, they seem to be roughly at the mid-way between the centre of the mirror and the rim of the aperture in the RM. At seconds 18 and 21 both simultaneously appear in the video.
With Hirata-san and Yano-san.
See pictures in SRM Remedying Work album.
We inspected the mirror with the super ultra high intensity LED lamp. It was very hard to take pictures but Hirata-san made a video:
- There are several dirt spots relatively far from the centre.
- There are about three dirt spots relatively close to the centre of the mirror. In the movie, they can be seen from seconds 10 through 12.
After the work, we checked ITMX can be ALIGNED state with Miyo-kun.
During work, we used picomotor for BF YAW and confirmed that ITMX rotated +YAW direction if we moved the picomotor REV direction.
We used 1000 counts for rough alignment and 100 counts for fine alignment.
Range is roughly 0.5 urad/step.
[Takase, Tomaru]
Post instead f Tomaru-san (Yesterday work).
They removed the first contact from ETMY but during the work, one magnet spacer was fallen off.
In addition, one magnet is fallen off from the spacer and two out of the others were easily pulled off.
They hopefully bonded the magnet to the magnet spacer yesterday and bonded the fallen spacer to the mirror today.
Date: 2021/8/3
Members: Dan Chen, Darkhan Tuyenbayev
Summary:
- We measured the optical efficiency between Tx module and Rx module by using a power meter (OPHIR StarLite"). We need detailed analysis, the rough values are:
- Path1: 96%
- Path2: 93%
- We measured the beam profiles, which we are analyzing.
- We can say the XPCal alignment is fixed.
I attached the measured power at each point.
Detailed analysis result will be reported soon.
Detailed report: https://dac.icrr.u-tokyo.ac.jp/KAGRA/DAWG/CAL/PCAL/exp_KAGRA/210803
Detailed report: https://dac.icrr.u-tokyo.ac.jp/KAGRA/DAWG/CAL/PCAL/exp_KAGRA/210803
[Ushiba, Tamaki]
Abstract
We researched why V1 sensor for ITMX MN didn't work correctly (klog 17699).
As a result, the loose screw may have affected adversely, so we drove it in. There might be other causes, so we will check the transfer function.
Detailed
As we reported last week (klog 17699), there were strange points in transfer function of MNV1 and MNH3 (DC gains of ITMX H3 and V1 are slightly smaller than those of ETMX's.).
So, we went to IX and investigated the reason of this.
First, we removed the cable which is connected to V1, then the signal of H3 reacted.
Next, we removed the cable which is connected to H3, then the signal of V1 reacted.
These reactions is the expression of the coupling between V1 and H3.
Then, we connected except for 3-8 pin (which is connected to LED), and there was no change.
However, when we connected 3-8 pin, we could see the same signal behavior as we removed the cable which of V1/H3.
This means the LED light may have created mischief so we decided to check it.
Before LED check, we replaced the cable which connected the satelite box and cross cable, but the signal had no change.
Moreover, we connected V1 cable to V2 port. Then, H3 signal didn't reacted, but we could confirm the responce of H2.
According to this reaction (cable sqapping solved problems), there are some defects in the vacuum chamber.
At this time, we thought LED light for V1 (V2) entered the H3 (H2) and made coupling between these sensors because V1 (V2) and H3 (H2) are very close to each other geometrically.
At last, we started the examination in the chamber.
As I menthioned above, we checked the LED light. We blocked the light of V1 and mesured how the signal changed using ndscope but we can't find the signal change.
However, we found the signal of V1 has strange points (larger vibration compared with other sensors → please see Fig.1) and the screw around V1 was loose.
Then, we drove the screw in, and the odd signal disappeared (Fig.2).
From today's activity, we concluded the loose screw had affected to the trouble with V1 but there may be other reason, so we will measure the transfer function again, and check V1 sensor works properly.
After the work, we checked ITMX can be ALIGNED state with Miyo-kun.
During work, we used picomotor for BF YAW and confirmed that ITMX rotated +YAW direction if we moved the picomotor REV direction.
We used 1000 counts for rough alignment and 100 counts for fine alignment.
Range is roughly 0.5 urad/step.
Follow-up of 17733
As entitled. To investigate what caused the fringe amplitude change, we started with shutting one of the Michelson arms on the POP table by putting a beam dump in front of the fiber output.
During last night, a beam dump shut out also the return light to PSL room.
So a PD at PSL room received just only the output light of Prometheus.
Akutsu-san put the beam dump around -17h in Fig.1.
Then, the fluctuation in readout value of the PD for X disappeared.
Fringe amplitude may be affected by fiber coupling at PSL.
By the way, I found K1:ALS-?_FIB_SERVO_.* was set up farther downstream than I had expected.
A figure in Mirror map became slightly old.
JGW-D1808971 is newer than Mirror map. But I heard it was not also the latest layout.
Follow-up of 17694.
Abstract: Checked the pzt range of the pzt-pico mirror to be installed on the POP table.
Details:
Using the setup described in17694, I applied DC offset to the PZT driver with the intrinsic dials (Fig. 1). For mirror 2, for pzt at 0 deg, 150 V appled (in the display of the controller),the beam spot is at 101.5 mm (Fig. 2), while 99.5 mm with no DC voltage (Fig. 3). And this taget was 5.4 m away from the pzt-pico mirror, so (99.5-101.5)mm/5.4m = 2mm/5.4m = -0.4 mrad would be the full range.
I check for the pzt at 120 deg and 240 deg in the same manner. Fig 4 is for applying 150 V to the pzt at 120 deg. Fig 6 is for at 240 deg, while Fig. 5 is for no voltage application. Comparing Figs 5 and 6, applying 150V to the pzt at 240 deg would cause, the horizontal beam spot moves from 2.5 mm to 4.5 mm (from "90mm" line), so 2 mm, so this is consistent the result of 0 deg.
[Takahashi, Sato, (remote) Ikeda]
We tyied to adjust the filter height for F0, F2, and F3.
F0: We found mismatching between the FR range and the keystone range. The ballasts (0.44kg x2) were added onto the F0. The FR range was measured and the limit switches were reset along the range. Relation between the FR height and the keystone height has hysteresis, so one ballast (0.44kg) was removed to set the keystone height to the setpoint.
F2: The keystone height passed through the setpoint once, but the keystone has reached upper mechanical limit. After that the FR didn't work at all.
F3: The keystone height was set to the setpoint using the stand alone driver.
With Hirata-san and Yano-san.
See pictures in SRM Remedying Work album.
We measured the height of the suspended lower breadboard (LBB) at the suspension points. Initially, the LBB was very high but we removed mass and it ended up very close to the goal of 380 mm:
- +X, +Y: 380.8 mm
- -X, +Y: 380.3 mm
- -X, -Y: 380.0 mm
- +X, -Y: 380.0 mm.
The total mass on the optical table was measured to be 35.7 kg. See the precise distribution of the masses in the notebook in this page and this other one.
With Hirata-san and Yano-san.
Pictures can be found in the album SR2 Remedying work after O3.
We measured the height of the suspended lower breadboard (LBB) at the suspension points:
- +X, +Y: 381.5 mm
- -X, +Y: 384 mm
- -X, -Y: 380.0 mm
- +X, -Y: 377.5 mm.
We also assessed the height of the pick up (steering) mirror mounted on top of the obelisk. The vertical center of the mirror was assumed to be indicated by a screw at the mirror holder. See the attached picture. In the picture, the laser level, which is at the nominal height, shows that the mirror is at the nominal height. We placed a ruler close to the mirror that showed the height is close to 381 mm (380 mm nominal).
Additionally, we also measured the height of the LBB in the region where the mid-size baffle will be: it is 379.0 mm.
Abstract
- The 2nd ADCs and AAs were installed in MCF0 and IY0 racks.
- The 2nd AA in MFC0 should be replaced someday.
- k1pemepics was renamed as k1pemmanage.
Details
Following items were installed in MCF0 and IY0 racks as the 2nd ADC.
ADC board (MCF0): S2113153
AA chassis (MCF0, U13): S1706450
ADC board (IY0): S2113154
AA chassis (IY0, U13): S1307459
Ch31 (last channel) of S1706450 may be broken. It has ~2.4V (4000ct) offset.
By unplugging the scsi cable between ADC adapter board and AA chassis, this offset was vanished.
But it didn't disappear by turning off power switch of AA chassis or replacing scsi.
So we had better to replace AA chassis in MCF0.
k1pemepics was renamed as k1pemmange because ^.*epics$ is not allowed as the model name.
safe.snap was newly defined as all channels were monitored.
master, rtsystab, testpoint.par were also updated.
[Takase, Miyoki]
Takase-san found a part of the motor of the draft chamber was broken and it stimulated into the motor body. When he removed it, the grounding (electrical leakage) was eliminated.
The reason why this part was broken seems to be because it kept rotating for 4 years!! after setting due to the air absorption power which was generated by a fan in the parking area.
So the lifetime of this part was over, then it has broken into several pieces, and one of them stimulated into the motorhead.
Anyway, the motor will be recovered on 5th August by the technical support of Yamato kagaku.
To avoid such unnecessary rotation, we will put a shutter or a route selector at the output of this draft chamber fan. So we should remeber that this shutter/router should be set at the proper position when you will use the draft chamber.
If you would like to use the draft chamber on 4th August, please contact Miyoki.
The streaming image is now available.
It also can be checked in the SEM page.
I installed a new router in room207 because the rooms far from the current router have poor connections to the network.
After this installation, the number of connecting devices is decreased to 8.
Detailed report: https://dac.icrr.u-tokyo.ac.jp/KAGRA/DAWG/CAL/PCAL/exp_KAGRA/210802
I checked several days data of fringe signals after unplugging the heater output cable. Then amplitude of fringe signals still changes in many times.
Bottom panel of Fig.1 shows that the amplitude still changed after unplugging the heater cable 5 days ago.
In last time, we were able to see the reproducibility of the relation between the heater offset and fringe amplitude.
I'm not sure this result was accidental coincidence or the real relation in a short term. But at least in a long term relation, there seems to be other reason why the amplitude changes.
The fiber output PD on the POP/POS tables are ones of the few non-control signal sensors for green laser systems, so I checked also these signals.
The fiber output power seems to change correlated to the change in fringe amplitude.
Fig.2 shows the fringe amplitude (upper) and the power at POP/POS tables (lower). In both X (left) and Y (right), the correlation can be seen between the fringe amplitude and the laser power at POP/POS.
Does this mean that the change is already occurring at the output laser power from the PSL room, rather than a change in the interference state or the power of return light from the POP/POS tables?
(Fiber coupling in PSL room, output laser power itself from Prometheus, etc.?)
Additional Information
Checking the status after replacing the relay switch
> BS:
> GAS: No problem
> IP,F0YAW:
> Power control: Power does not turn on, ping fails
> Limit SW: Not confirmed.
=> GAS, IP: No problem
> PR2:
> Power control: Script startup fails, so maybe power is not turned on, and ping also fails.
> Limit SW: Not confirmed
=> PR2: no problem
As already discussed in the control room, please in advance share what you will do and have discussion among us (on-site optical commissioning cores, which I am just calling), when you touch to change hardware. Please; I think you have noticed most of us in the control room do so (exchange information, and have discussion) like after the tunnel work...