We got the following message in JST,

• 2025-01-12 13:12:16.893314 GV_BSY GV is closed GV_BSX GV is closed.
• 13:12@miyoki@uchiyama@Nobuhiro KIMURA [vacuum-alert] out of the nominal range 2025-01-12 13:12:32.844101
• KGRVAC_CCG_BSY_01_VAL_PRESS:  current=8e-06,  threthold=8e-06

Then, actually, we confirmed that GVs were closed. As before, the vacuum level at the MICH area started increasing because of the loss of the powerful cryo pumping effect of IXYC cryostat themselves.

Fig.4 and 5 show temps in shields of IXYC cryostat. In IY, 4K bar ref and 8k shields reached around 35K which is the near the temp of the nitrogen adsorption temp (~ 30K). Is there any other temps at which some gas is adsorbed? On the other hand, in IX, these temps reached ~23K which is below the nitrogen adsorption temps.