KAGRA Logbook

VIS (BS)

fabian.arellano - 12:18 Friday 08 November 2019 (11423)

Drift due to tempearature.

Currently the position control signal of the top filter is around 23,340 counts, which we should consider it high. Medium size signals are the ones for the SF and IP-H2.

The figure shows the minute trend for the lastest 60 days, including the temperature of the clean booth. On the 10th of October the temperature reached 24 degrees and it has drifted 0.8 degres to reach 23.2 degrees early this month. Today it's 23.3 degrees.

It would be suitable to recover the temparature, otherwise we would have to use the fishing rods.

The temperature we had originally requested ca be found in entry 7420.

Images attached to this report

Comments to this report:

shinji.miyoki - 14:29 Friday 08 November 2019 (11431)

Please hold your action about fishing rod adjustment.

Temp is now recovering in the corner station with a 1.5kW heater as an attached file

Temp will be tried to be more recovered maybe in the next Monday by using more heaters in the corner station.

Images attached to this comment

shinji.miyoki - 15:35 Friday 08 November 2019 (11434)

The temp changes are

SRM : +0.2 (22.4 10:00 -> 22.6 15:30 8th Nov) why so low temp ??
SR2 : +0.3 (23.4 10:00 -> 23.7 15:30 8th Nov)
SR3 : +0.3 (23.9 10:00 -> 24.2 15:30 8th Nov)

Did you see any recovery in the suspension system ??

shinji.miyoki - 7:28 Saturday 09 November 2019 (11449)

The temperature rapid enhancement seemed to be due to rapid heating function of heaters.

The present temp enhancement is almost a half of the max enhancement.

I am afraid automatic turn off of heaters.

A defumidiifer in IXV seemed to keep working in this time.

Images attached to this comment

shinji.miyoki - 12:12 Saturday 09 November 2019 (11451)

(corner)
One heater seems to be alive now. Setting is 24C.

Consequently, the temp enhance effect is almost 0.2 for all places after rapid heating mode as an attached file.
It is roughly consistent our expectation.

If we need ~1C enhancement, it might be better to stop BS-C cooler.
If 0.5 enhancement, more heaters are desirable.

I will try to set 25C. however. If the heater automatically sets the present heating power, temp setting of a heater is nonsense.

(Yend)
Two heaters seem to be alive now. Setting is 23 C.

Same performance with corner. After a temp enhancement peak,

1F EYC : 20.1 (20.4-5)
2F EYC : 20.7 (20.6-7)

() shows desirable temp? according to http://klog.icrr.u-tokyo.ac.jp/osl/?r=11429

I will try to set 24C.

(IXV)
22.5C that is previous stable level is obtained now. I hope the defumidifier keep working in this time.

Images attached to this comment