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    User name jpchen

    Log entry time 00:11:50 on October25,2007

    Entry number 209497

    keyword=Target partially vented during the day shift. Vacuum degraded.

    Loop 1 (high pressure Helium) pressure was 178 psi at 8 am this morning. The chart at 4 pm already showed only 135 psi. Appearantly, it went through a partial vent during the day. As I was told that when Hall C doing the target cool-down, there was a temperature jump
    for loop 1 at some point. That probably was when the partial vent happened.
    We will leave it as it is until the hall opens tomorrow morning. At that time we will re-fill it back.
    Also noticed that the scattering chamber vacuum degraded. It was
    ~1*10-6 before, but it is now ~9*10-6! Need to watch carefully.