IFO summary (11th ~ 13th)
Basically, stable operation until 13th early morning. The longest continuous lock was 11h 51m. After recording this longest lock, we found,
Y arm GR phase lock fringe became so small. -> temporally we adjust the mid fringe position. The adjustment instruction was already posted by Sugimoto-kun. If possible, we will try.
- A strange LSC-LOCK guardian code seemed to force the IFO unlock just after Observation mode start. This statement was commented out.
- MCo coil outputs seem to have large offset. Kokeyama-san will off-load in some timing.
- In the early morning on 13th April, the ocean became super violent, then IFO cannot be locked. So we gave up the IFO lock and decided to keep only alignment hopefully until the Tuesday morning, or Tuesday midnight in the pessimistic case. The full alignment maybe from IMMT1/2 for enhancing POP90 will be done in this case. Anyway, the Monday shift until 9:00 on Tuesday was canceled. I will inform more about our plan later
- The planed CAL tasks during maintenance will be done after this recovering IFO. 3 or more hours will be allocated.
General information from KAGRA office
(1) R41 conditions
Route 41 has been affected by the slope collapse at Katakake in Toyama City. The route between Katakake and Inotani is closed to traffic from April10. As a result, the direct bus service between Toyama Station and Mozumi has been suspended. Also, regurar size cars can take the detour route to Kamioka. The JR Takayama Line and the buses between JR Inotani Station and Kamioka are operating as usual.
国道41号線は富山市片掛（道の駅林林付近）での法面崩落の影響で、 4/10より片掛ー猪谷間が通行止めとなっています。 このため、富山駅ー茂住間の直通バスが運休となっています
富山国道河川事務所 http://www.hrr.mlit.go.jp/toyama/ ※迂回路無しとありますが、神通川対岸のルートで迂回可能です。 道が狭いので運転には注意して下さい。
(2)COVI-19 situation in Toyama and SK/KAGRA temporal plan
Toyama Prefecture has also become a pretty dangerous area. I basically recommend you to take"Telework" as a response to it.
But the staff who maintain the KAGRA run should come to Kamioka site. If you come to Kamioka site, please send e-mail to
Situation will change daily, but please deal with it calmly. Thank you for your cooperation.
Masatake Ohashi Director, KAGRA Observatory
(3) Saito-sensei's mother has died. We would like to send our condolences to Saito-sensei on the loss of his mother.