Repeat emittance scan of present 18O4+ beam. It compares okay (somewhat broader emittance numbers)  with yesterday's scan. Also attached is FC6 beam overnight. Nice.

Proposed run plan for this time:

• Document TIGRESS tune.
• 18O4+ emittance scan.
• Mass scan A/q = 0 to 25.
• Repeat 18On+ emittance scans at present RF frequency. 
• 16On+ emittance scans at present frequency.
• Plot 16On+ & 18On+ emittance on one graph.
• If indicated, then do 17On+ background study.
• Open 17O gas bottle to system.
• 17On+ resonance survey based on 18On+ results.
• 17On+ emittance scans.
• Add 17On+ emittance values to graph.

I have begun a mass scan from 0 to 25. It will be a while. Data file: masscorr_mcis__0-25_090714.txt. 25nA of 18O4+ restored to FC6.

We have a change of schedule. Due to circumstances, Sophia will continue tuning to TIGRESS this morning. Sgan Development will resume this afternoon.

Details: The beam path through the TIGRESS chamber is clear presently, and no detectors are mounted. It is the perfect time to send a nA pilot beam to the end of the line. TIGRESS intends to install electronics starting at noon. Sophia expects to have tuning comfortably completed by then also. She and I have agreed to the following schedule: 

Note: An SC vacuum issue arose this morning, which truncated Sophia's tuning efforts for today. We have agreed to a slightly earlier handover time on Friday, so that she can tune through the chamber. It will be more difficult, as there will be detectors installed by then.

Beam has been on FC6 for an hour or so. It looks pretty good. Stripchart attached. Save: 090714_1231.snapmcissebt3a. Note: There is something fishy about the slit panels. I think an IOC got rebooted somewhere along the line, and the slit motors are out of calibration. I have recorded the pot values in the save file. Emittance scan of Sopohia's 18O4+ beam appended.

As noted, Keerthi was called to restart the source after a power bump. He continued Supernanogan development through the night (can you imagine?!?). He made some great progress. Here is a partial summary of his findings.

Actions taken: frequency scans across the entire range from 12-16GHz for each charge state of 18O.

For 18O4+, the "perfect" resonance occurred at 13.00GHz, with other resonances at 13.26, 13.54, 13.74... i.e. at about 26MHz intervals. The lowest resonance is the least noisy. However, if it trips, it is also impossible to restart it without playing with the RF. Based on Keerthi's instructions, I have written up a draft of an ION note for Operations, describing how to restart the Supernanogan source if it trips. I have asked the operators to critique the draft. The present RF state is attached below.

An MCIS vacuum trip occurred somewhere around 15:30. Sophia observed a drop-off in beam. The cause looks like the PLC-related business that we have experienced many times before. This fault has not manifested itself for quite a while, since Controls firewalled the MCIS portion of the network on March 30th.

As per our agreed deal last week, today is reserved for Supernanogan tuning to TIGRESS. Development will resume tomorrow.

There was a power bump overnight that knocked out many systems, including OLIS. The ISAC elog mentions something about it here. It seems that Keerthi restarted the source. (Note to self: Write an ION with brief restart instructions for the Supernanogan.) 18O4+ beam was left on FC6, and it is very nice, as you can see. Sophia has the beam now.

The Supernanogan was restarted this morning, after last night's power bump. 18O4+ on FC6, cooking for about an hour. Looks very good. Keerthi is doing frequency scans today to find best resonances. Time permitting, he will do this over a range of 18O charge states. He is also developing a dual-mode (MCIS/MWS) IOS tune. At some point over the weekend (my guess is tomorrow evening), he will open the 17O source gas bottle to the system.

The Supernanogan was restarted this morning, after last night's power bump. 18O4+ on FC6, cooking for about an hour. Looks very good. Keerthi is doing frequency scans today to find best resonances. Time permitting, he will do this over a range of 18O charge states. At some point over the weekend (my guess is tomorrow evening), he will open the 17O source gas bottle to the system.

Here is a striptool of 18O8+ beam (magenta trace) last evening from about 18:00 to 22:30 when there was a large power bump coincident with a plane crash in Richmond last night. Before the trip, beam current was about 20epA on FC6 (normal bias).

Keerthi did some 18On+ frequency scans this morning. He observed 18O8+! I am attempting to repeat it myself now. Reverse bias on FC6.

Peaks at:

13.0277GHz => 1epA (unstable)

13.1023GHz => 1epA (unstable)

13.1695GHz => 10epA (unstable)

13.1672GHz => 20epA (unstable) stripchart attached

13.006GHz => .7epA stripchart at 17:24 attached

First, optimize current versus frequency and amplitude. Unfortunately at 5dB the beam blinked out. Go fishing, then find it again. Attached is stripchart at 17:30, where I was optimizing, then switched bias to Normal, then watched beam blink out. Then stripchart at 17:49 shows beam back again, reverse bias on the left and normal bias on the right: ~10epA. RF settings also attached. Minutes later, beam is still on. FTR, the original RF is appended at the end.

The 18O source gas bottle is online. The ion source was optimized for 18O4+ and kept the same throughout. Emittance scans of each charge state of 18O were attempted. Visible scans were found for all states up to 6+. At least one more set of scans is desireable. Present beam is 18O4+. Next up: RF frequency survey with 18On+.

A/q = 2.25 FC6 at reverse bias MB = 736.9G @ 42.9A

Not enough intensity for an emittance scan. Possibly on the edge of A/q=2.3 (23Na10+?).

A/q = 2.57 FC6 = 0.25nA MB = 790.0G @ 46.2A

Not enough intensity for an emittance scan.

A/q = 3 FC6 = 5.5nA MB = 851.5G @ 50.1A

A/q = 3.6 FC6 = 12.5nA MB = 931.8G @ 55.3A

A/q = 4.5 FC6 = 29.5nA MB = 1041.8G @ 62.4A

A/q = 6 FC6 = 49.5nA MB = 1201.4G @ 73.1A

A/q = 9 FC6 = 50.0nA MB = 1470.8G @ 90.8A

Here we go. A/q = 18 FC6 = 141.0nA MB = 2078G @ 130.2A