After their EOB with 17O3+ yesterday, DRAGON switched to 21Ne4+ running for charge distribution studies. Keerthi changed over the source gases for that around 08:30 yesterday. Things went well. Beam intensity dropped off and leveled off overnight. I tweaked up the source just now. Current at H2:4 moved from xe-10 to ~1.5enA. A stripchart is attached. Orange trace is H2:4, and green is COL0, which reflects total beam from the source.

Later around 11:00... a controls event happened. Cleared all SPs, etc. Of course that turned off the source. Restart okay. 3.8enA on FC6. Beam observed to H:5 (energy change in progress). RF screenshot attached, and also what the Compare utility displays right now.

Later... around evening... DRAGON experimenters reported that delivered beam couldn't possibly be 21Ne, based on certain charge ratios they see and calculate. A couple of hours OTP with ICR to discern masses, in particular 20/21/22 series at +1 and +4 positions. We are pretty confident that 21Ne4+ (A/q=5.25) is sitting at ~1160G or so. Previous running had been at some 1170G, which we believe is the next peak up. (It later was found to be 16O3+, i.e. A/q=5.333.) Based on that setup, ICR attempted to get beam through the line. They got it as far as the front of the DTL, but that was it. Then they returned it to the higher field value and sent it through, but no joy for DRAGON.

Next day, Wednesday: Keerthi did careful mass scan and A/q re-calibration. Then Sophia looked at the situation. When she was done and the experimenters online by ~midday, the separator was reported sitting at 1160.75G. Separator field chart for the period is attached below; red is field, green is A/q. The run concluded uneventfully somewhere around 21:00 on Wednesday evening.