SASE2 vacuum incident
7h10 : MID informs PRC about a vacuum incident in the SASE2 tunnel which tripped the beam. Instructed to contact directly VAC-OCD
8h26 : VAC-OCD informs that investigation is ongoing, but beam can be delivered. This kind of trip usually occured rarely
and usually can be reset by VAC. Apparently the source of the issue is at the XTD1 solid attenuators.
8h36 : MID confirms to PRC that already 3 trips occcured but the experiment so far can continue. Beam delivery continues.
10h11 : VAC-OCD informs that now there is a bigger more wide-spread issue with the XTD1 vacuum system
and beam operation is stopped for at least 1 hour. VAC group and DOC are working on the issue.
11h : It turns out that the vacuum bellows of the 2.4mm diamond attenuator in SA2_XTD1_ATT has a leak, which is worse and
not acceptable in terms of vaccuum in the extracted state (bellows elongated) but less severe in the inserted state (bellows compressed).
12h33 : info by VAC: issue is temporarily solved by blocking the 2.4mm diamond arm in the IN position. Must clarify today how to proceed further.
The vacuum issue thus is temporarily solved, beam permission is back,
12h38 : Beam coming back to MID. MID can work today with this ATT always inserted, but not for the weekend. |