 Wed Jun 3 16:17:51 2009, Damien Gallop, Routine, General, MWS started for 18O1+ production to TIGRESS
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A couple of weeks of 17O3+ to DRAGON ended yesterday with a photo finish. Supernanogan went off at 10:00. Preparations for 18O began. Main event for
yesterday: Replace IOS:TP7. Edi Dalla Valle reported that he had just received a V550 with Conflat flange. "Our timing was perfect." It is working
well. The system was under vacuum again by around noon, and pumped overnight. This morning IG1 was ~5e-7 Torr and IG4 was ~2e-7 Torr, where those two gauges |
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Thu Jun 4 10:46:37 2009, Damien Gallop, Routine, General, 18O source operation overnight
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The MWS delivered 18O overnight, mostly onto FC6. Sophia complained about source stability this morning. It definitely could be improved. Yesterday Keerthi
did some online tweaking of the RF power for stability, with little improvement. The IOS pressure today is about 2e-6 Torr, so I believe the 18O pressure
is too high for good operation, although the brightness is great. The base pressure is about 4e-7 Torr. Tuning is in progress. Given an opportunity, I |
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Mon Jun 8 09:31:39 2009, Damien Gallop, Routine, General, Emittance scan of 18O beam from MWS
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The TIGRESS run ended this morning. Supernanogan Development begins now for two weeks. Begin an 18O1+ emittance scan and also take some fast FC6 current
measurements before we switch over. |
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Tue Jun 9 16:53:55 2009, Damien Gallop, Routine, General, Supernanogan development in progress
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Keerthi started the Supernanogan source today. His primary goal was to test out Rick's theoretical tune calculations. He was ecstatic with the results.
Rick's table gives a tentitive value for the Einzel lens. In fact the ideal value is at or even higher than the bias voltage. However, Keerthi experieced
sparkdowns at those voltages. Rick's calculation gives a reasonable number for better than 50% transmission between MCIS:FC0 and IOS:FC3. The Enzel lens |
Tue Jun 9 20:49:32 2009, Damien Gallop, Routine, General, Supernanogan RF & IOS slits 
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I have been testing various RF power settings for cold starts and beam stability. No surprise, the best tuner setting is approximately midway at about
58%. Different slit selections tested. Emittance scans in progress. Done. |
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Wed Jun 10 11:22:59 2009, Damien Gallop, Routine, General, Supernanogan development mass scans
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Main event this morning so far: mass scans and post-scan analysis using Gabe's tools. We have a pretty good recipe now. Tight scan to mass 20 in progress.
Later... good scan. Geoff and I did a dry run of our presentations for Friday morning. We used the Auditorium computers, etc. After some small teething
pains, everything went well, including a cold start-up of the source. The 17O3+ emittance scan was taken quickly. Pretty good outcome anyway. The mass |
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Wed Jun 10 17:49:40 2009, Damien Gallop, Routine, General, Beam to RFQ
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We handed over the beam to Sophia for testing Rick's new tune. Although there are RF issues at the RFQ presently, her feedback to the operators is so
far, so good. TBC tomorrow morning. Right now, we will open the OLIS cage and install a couple of source gases in preparation for our presentation on Friday. |
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Wed Jun 10 18:48:53 2009, Damien Gallop, Routine, General, Krypton source gas fitted
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Krypton source gas teed directly into ion source. A Nupro valve and tee also added for 17O line. At present, the 17O gas bottle valve is closed. The
Kr bottle has an integrated leak, so this bottle is opened to the system now. Pumping in progress. Pressure is already <3e-7 Torr. I will restart the
source shortly. |
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Thu Jun 11 12:10:22 2009, Damien Gallop, Routine, General, Supernanogan status
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| Pumping went well overnight. TP3 turned on around noon. Issues with Kepco communications. |
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Fri Jun 12 14:12:04 2009, Damien Gallop, Routine, General, OLIS & Supernanogan Facilities presentation
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Presentation this morning in Auditorium. Players:
Keerthi: science
Geoff: engineering |
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Fri Jun 12 14:24:49 2009, Damien Gallop, Routine, General, 17O3+ beam at optimized RF
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A comment about RF power came up at the presentation this morning. Intense X-rays can be produced not only at the peak efficiency and output of the RF
amplifier but also as a function of other parameters including source gas pressure, isotope(s), whatever you can think of. I set the RF at a mid-level
power, with power setpoint at 0dB and adjusted the RF for optimal current on FC6. This occurred at 13.0306GHz with 35W power. About 6nA of beam. Take a |
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Mon Jun 15 17:49:23 2009, Damien Gallop, Routine, General, 84Kr charge states begun
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We began looking at 84Kr this weekend. Keerthi had 84Kr19+ on FC6 this morning, which I was able to tweak up from ~300epA to about 600epA. Not bad! This
evening it is down to 100pA at best. I think there is a correlation of multi-charge production and room temperature. (It's warm today.) Keerthi noticed
tat an entire mass scan this afternoon was suppressed, where I had a solid scan earlier, the two taken the same way. Let's see what happens to FC6 overnight. |
 Tue Jun 16 12:10:17 2009, Damien Gallop, Routine, General, 84Kr charge states begun
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Damien Gallop wrote:
We began looking at 84Kr this weekend. Keerthi had 84Kr19+ on FC6 this morning, which I was able to tweak |
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Tue Jun 16 16:47:02 2009, Damien Gallop, Routine, General, Mass scan around 16O5+
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Keerthi suggested using 16O5+ for optimizing the source. I did a tight mass scan in that area, and 16O5+ is clearly visible. I will use it for some source
tweaking. Also, I used Gabe's calibration program to slightly adjust the values of the two constants. There are some 10nA of 16O5+ on FC6 presently. Final
settings for today, etc. are attached below. |
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Wed Jun 17 10:14:57 2009, Damien Gallop, Routine, General, 16O5+ on FC6 overnight 6x
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The 16O5+ beam stayed up OK overnight. ICR took some emittance
scans this morning. They look interesting. A finer resolution scan is in progress presently. Goals today:
1. Comprehensive mass scan to A/q=100 |
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Wed Jun 17 17:01:07 2009, Damien Gallop, Routine, General, 16On+ emittance scans
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A series of 16On+ emittance scans. Benchmark scan of 16O5+ matched well with same scan done this morning. Subsequent scans beginning with 16O1+ were
thwarted by an IOSIOC seizure in the emittance rig EPICS panel, and an IOC reboot was required. ICR restored last saved DRAGON tune. So far, so good. Ah,
well, not so fast. I have to go fishing for beam on FC6. This may take a while... That's it for today. |
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Thu Jun 18 09:38:52 2009, Damien Gallop, Routine, General, Check Supernanogan beam after IOC reboot yesterday 15x
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As mentioned before, IOSIOC was rebooted yesterday afternoon to unfreeze the emittance rig panel. It cost us our tune, which unfortunately wasn't saved
very well. Lesson learned: Save often. I will run a mass scan now and check the mass correlations calibration. Then I will pick up with some 16On+ emittance
scans. Keerthi was here until late last night working with the beam also. He will have some results for sure. |
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Fri Jun 19 11:59:49 2009, Damien Gallop, Routine, General, 16On+ emittance scans continue 18x
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Keerthi developed a nice 16O7+ beam to FC6 last night. Beam current is about 3nA presently. Here is the first emittance scan from 11:05 today. A little
spotty, but it's there. Higher resolution scan at 13:58 follows.
The third plot at 16:12 is 16O6+. |
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Fri Jun 19 20:15:19 2009, Damien Gallop, Routine, General, Summary of 16On+ emittance scans
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Here is a list of 16On+ emittance scans for today. Although IOSIOC got rebooted, restored tune was identical and trouble-free, and RF was untouched.
Save file: 090619_0859.snapmcisfc6. Emittance values: pi-mm-mrad
at 39%, 63%, 86% and 90% respectively. Here we go. |
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Mon Jun 22 16:00:04 2009, Damien Gallop, Routine, General, Emittance thoughts and other matters 7x
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An emittance scan of the 16O7+ beam follows. Also, a stripchart of the same beam on FC6 overnight. Keerthi did some studies over the weekend. He found
that the characteristics of the amplifiers behind FC6 and the emittance rig cup differ significantly. That's disconcerting. We did a visual this morning,
and confirmed that the amplifiers are identical VME modules in the same crate. He believes it's a scaling thing. We will test again with a current source |