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

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

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

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

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

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

Not enough intensity for an emittance scan.

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+?).

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+.

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.

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).

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.

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.

MCIS TP1 is not running well. Needs investigation as soon as S1219 is completed.

Later... TP1 failed completely, and we are running without it. Starting late Saturday night, DRAGON began to observe a certain instability. We correlated it to MCIS:COL0, which skims total current continuously. It is pretty evident that the source is now toggling between two adjacent plasma modes, due to the somewhat higher vacuum at MCIS. Vacuum was something in the 7-8e-8 Torr range before, but has settled out at some 1.25e-7 Torr now. General consensus is to continue running like this, as it is a minor effect, as you can see below (blue trace). DMG

090915_1915ILTEMIT.txt = 17O +3,  4.4uA new tune, scanner offset +10V,  scanner scale 100nA , 100x50 matrix

090915_1929ILTEMIT.txt = same as above with 200x100 matrix

090915_1949ILTEMIT.txt = after tune tweaking (not optimal; for reference only)

090916_1156ILTEMIT.txt      17O+3  good settings 50x100 ,   333nA Scale, ~4uA

090916_1206ILTEMIT.txt      17O+3  good settings 100x200 ,   333nA Scale, ~4uA

090916_1222ILTEMIT.txt  Changed the MCIS steering to center the beam in the EL. 17O+3 ~5uA, 50x100

Source started at 800W of microwave power and 2cc/min neon gas easily. New magnetron produces more power than the old one.

We should try to keep MW power under 500W during running and use only 800W for ignition.  EE left off for the night.