 Fri Jul 17 10:32:42 2009, Damien Gallop, , , 16O8+ recheck 
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| A/q = 2 Field = 667.3 FC6 = ~10enA |
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Fri Jul 17 10:46:06 2009, Damien Gallop, , , 16O6+ recheck
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| A/q = 2.666 Field = 767.1G FC6 = 3enA |
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Fri Jul 17 11:10:21 2009, Damien Gallop, , , Supernanogan development done 6x
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Beam switched back to 18O4+ by 11:00 as agreed. Some glitches. Here are snapshots of how it looked at handover time.
Later... Sophia prefers using all previously-saved files including ion source. Okay.
Note: For fun, Controls took away isacwserv mid-morning. The ICR did not communicate to them that I was the user... Workaround done with Keiko. |
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Mon Jul 20 09:25:35 2009, Damien Gallop, , , 18O4+ run to TIGRESS complete
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The 18O4+ run at about 5MeV/u ended this morning with reasonable success, I'm informed, despite MCIS vacuum trips, SC cryo trips and a power bump for
good measure.This morning I found beam at FC6 unstable. It appeared to be toggling between plasma states. A little tweak of a few MHz up in microwave frequency
not only stabilized it but also multiplied the brightness. Too bad the users didn't have this beam. Emittance scan in progress now. |
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Mon Jul 20 17:28:01 2009, Damien Gallop, , , MCIS cart removed from cage and parked
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We discussed whether or not to leave the Supernanogan in the OLIS Faraday cage, and decided no, because the up-coming runs will use the MWS at 42 and
52kV respectively, higher than the MCIS HV rating. Bonus: We have more working room in the cage. The cart is out and parked. Services are connected and
up. |
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Tue Jul 21 17:11:33 2009, Damien Gallop, , , MWS preparations for 21Ne operation
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With the MCIS cart removed, Geoff hooked up the leak detector to the MWS source gas line. He did a couple of hours of leak checking in this mode. Then
he moved the connection to an empty gas port on the manifold itself. Much qicker responses. We replaced a VCR seal on the bottle side of the right-hand
He solenoid valve. That did wonders. He checked around afterwards, but found no further leak. We tidied up and opened the manifold to IOS. Base pressure |
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Wed Jul 22 01:33:29 2009, Damien Gallop, , , MWS initial startup summary
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Vacuum came down to ~7e-7 Torr. On startup, bias sparked over somewhere. Vacuum leak was caused. Later we found that HV had sparked through the source
gas tubing, which was touching the beamline frame. Obviously an arc had formed within the tube and sparked through on the ground side. We also could not
reset the bias interlock (ICR has efaulted this), so we ran in local. System is set up for 21Ne with about 28nA on FC6. Bias is off for the night, while |
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Wed Jul 22 14:31:28 2009, Damien Gallop, , , 21Ne setup to TUDA-II is underway
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Last night Keerthi resolved the sparking issue in MWS and started the source while I was present. There was a frozen interlock condition ion IOS:BIAS,
which Graham resolved today. HV was on by ~11:00. Beam on FC6 immediately. It looks like Sophia took the beam at that point. I noticed that the Kepco appears
not regulating, and in any event is close to a limit (0.3A). I have asked Sophia for five minutes to reset it. |
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Mon Jul 27 14:39:22 2009, Damien Gallop, , , 21Ne5+ to TUDA-II
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21Ne has been available from the MWS since mid-week. Here is roughly how last week unfolded to now:
Monday: MCIS -> MWS and remove MCIS cart
Tuesday: leakcheck MWS source gas manifold |
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Mon Aug 3 08:39:31 2009, Damien Gallop, , , MWS 21Ne -> 25Mg switchover
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Conveniently scheduled for BC Day, we are preparing to switch over the MWS to sputter operation with MG source material. Operations has saved present
21Ne tune.
Later... Done! Source is relit with 21Ne beam on FC6. |
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Tue Aug 4 11:13:04 2009, Damien Gallop, , , MWS source tuning for 25Mg operation 6x
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The source stayed up overnight just fine, with a little 25Mg beam on FC6. This morning I did a few mass scans to get a fix on Mg positions. Short story:
There are some 3nA of 25Mg on FC6 presently, with things less than optimal. Stay tuned.
Attached is an early graph of Mg beams produced with the MWS almost exactly five years ago. Best I could find for now. |
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Wed Aug 5 11:29:51 2009, Damien Gallop, , , MWS operation overnight and 25Mg status
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So... there evidently was a power bump overnight, because the stability power supply was "disconnected" from the system. This happens every
time there is a power bump. It's a serial port thing. Meanwhile, the source also tripped. Upon restart, nothing was the same. This morning, we found that
Q3 was current-limiting on one element. We have asked Rick to develop an alternate tune for us. |
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Thu Aug 6 17:02:00 2009, Damien Gallop, , , MWS 25Mg tuning to TIGRESS in progress 7x
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Tuning has been on-going through the day. Here are a couple of emittance scans taken in-between heartbeats. The first is zoomed out, the second zoomed
in a little close. We managed to sneak in a third also. |
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Fri Aug 7 10:16:38 2009, Damien Gallop, , , MWS 25Mg emittance scans 6x
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While there is an SC cavity issue, I have been repeating last evening's emittance scans. Here is the best one. About 70nA of 25Mg on FC6 presently. Note
that emittance rig Faraday cup is reverse-biased. Also, overnight stripchart appended. You can see a gradual increase in current draw on the EE power supply
as there is a build-up of Mg. |
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Fri Aug 7 14:42:29 2009, Damien Gallop, , , MWS 25Mg beam reduction
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Around noon, Keerthi adjusted the PE down to reduce the intensity of the Mg beam, as we are running with attenuators in. He ended up with about a 30%
reduction, and improved the noise band by about 3x in the process. Here is a repeat emittance scan. Both sets of slits are at 2.5mm position. I also
took the opportunity to reset the separator stability equipment again. |
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Mon Aug 10 16:12:28 2009, Damien Gallop, , , MWS 25Mg operation over the weekend
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Summary: good.
Details: A trip occurred at some point. I restarted the source over the weekende remotely. I have been tweaking down the PE since. Looking mighty
fine. Stripcharts attached. Separator field nicely flat too, with stability program running. Save: 090810_1605.snapiosfc6 |
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Mon Aug 10 16:36:33 2009, Damien Gallop, , , MWS 25Mg emittance scans
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A series of 25Mg emittance scans for Rick.
Starting scan with everything as-is, i.e. slits closed.
Data file: 090810_1621ILTEMIT.txt |
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Mon Aug 10 16:43:59 2009, Damien Gallop, , , MWS 25Mg emittance scan with slits open
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Before proceeding, I nudged in each of the slits, watching for first clipping. With the current emittance (nice), the beam cleared both slits completely;
the upstream slit began clipping at about 1.5mm, and the downstream one at about 2mm. Also, FC6 current with slits in/out was: ~30nA / ~57nA. Note: I had
to change the scanner parameters a little. |
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Mon Aug 10 17:16:20 2009, Damien Gallop, , , MWS 25Mg emittance scan with downstream quads off
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Here is the emittance scan that Rick requested, beam with Q4/5/6 off. Note that present numbers for these quads do not match theoretical. I repeated
my slit nudge check for clipping, just in case. As before, no clipping for the first mm or more.
Data file: 090810_1713.txt |
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Mon Aug 10 17:20:55 2009, Damien Gallop, , , MWS 25Mg emittance scan with zeroed vertical steerers
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Here is a variation I thought might be appropriate.
Data file: 090810_1724ILTEMIT.txt |