The source stayed up quietly overnight with about 4enA on FC6. Once in a while a little burp occurs, visible as small beam and vacuum spikes. I have tweaked the RF frequency up a little for better centre of range.

I alsmost want to write, see yesterday's entry! Source ran quietly with no interruptions. FTR, the separator stability program is also percolating along nicely. It was taking hits from nearby EMI until I added a ferrite split core to its USB cable at the computer end.

The Supernanogan was on overnight quietly. FC6 went in this morning. (Didn't check if fingers were involved.) I  now notice a strange pulsing in our Stripchart. See what you think. Note: field and A/q max scales are orders of magnitude higher than real life.

Later...At around 14:00 I added ferrite cores to the field probe cable at the CANbus interface box. That clipped the high side of the pulses completely. If I play very carefully with the field range, I can get small artifact-looking pulses to appear since I installed them (see 17:16 chart). In the meantime, I found that, contrary to appearances, the field stability program was not really regulating. A remote reboot of the server cured it.

Beam stayed on quietly overnight, as did the separator stability program. Periodic pulsing continues to occur. No explanation has been proffered so far. Adding ferrite cores appeared to clamp the high spikes, but high spikes reappeared around midnight. There does not appear to be any real effect on the beam or separator.

On Friday we left 33S5+ on FC6. The separator magnet power supply tripped at some point for unknown reason. The operators turned it on again overnight. Keerthi tweaked and tuned early this morning and just recently. Beam is back to FC6, but displayed A/q is off, though the actual beam is correct.

I had optimized the RF yesterday, but the source went into a dual-mode toggling regime. It is hairline to find a nice point. I also found that it responds better if frequency is approached from high to low.

Later... After some tweaks earlier, beam is looking pretty good, a solid 3enA at FC6.

BTW, we are still running with the same SO2 gas settings as before, i.e. the calibrated leak valve just barely cracked open. Under the circumstances, it's a sweet spot for us.

Later... Another blip on the field probe at 16:15. Coincidentally the beam took a little hit. Here are the Stripcharts (tight zoom and normal zoom).

Beam was quiet overnight. I noticed a slow drift that seemed to follow the source pressure. My best guess is that our source gas "regulator" is a little coarse at these flows. Save: 091028_0935.snapiosfc6

Controls is rebooting IOSIOC. I have inserted MCIS:FC1 for the duration. Let's see what comes of it all.

Later... As expected, the reboot zeroed our optics. ICR issued a FR#4179 on it. Meanwhile, I rechecked the A/q calibration, and found it off a little. Below are before and after shots. The latter shows scanning in both directions. I didn't expect this large a hysteresis. On the other hand, the crossover points make nice reference points for known A/q values.

Later... Controls is investigating the FR! MCIS:FC0 in, and let them 'ave at 'er.

Yesterday there was an IOSIOC reboot for a purpose. It was an opportunity to demonstrate to Controls that IOSIOC reboots materially affect the IOS section. Controls responded to an ICR fault report on it, and have not reported back to ICR so far. The source was off overnight and remains off now. I have informed ICR that if nothing happens this morning, I will restart the source after lunch.

Later... Jane reports that there was a problem, and it's been solved. We have to request that MCIS PVs get restored after a reboot. Done. Restart stuff. Much of IOS was already on.

Controls finished with IOSIOC work yesterday. ICR had restored most optics. I restarted the source last evening. As you can see below, the beam grew nicely overnight. Sometime today I will ask ICR to reboot IOSIOC and see if everything stays up now.

One more thing. The chart shows the last couple of days' running. Prior to beam-off for IOSIOC, we observed periodic spikes of about 45m each in the separator field readback. Now the readback is clean. We did not make any changes on our side. Only the IOSIOC work was done. Interesting, no?

Noon: ICR is rebooting IOSIOC right now. So far, normal whiteout plus MCIS optics is also white. CANbus page is also white, as I expect it to be.

12:15: IOSIOC is up, but 'most everything else is down. That's disappointing.

Later: Controls is looking into it. They have the optics for the afternoon. I will restart the source at the end of the day today.

Much later: Beam is on. ~3enA

Beam came up nicely on  Friday, and stayed up quuietly over the weekend. Note the absence of periodic spikes in the separator field readback since the last IOC reboots.

Later... I have asked ICR to make us a nice emittance scan. (They are running beam at 8pi presently as well.)

Later... Well, nothing's ever simple. Eventually the emittance scan controls froze up, requiring an IOSIOC reboot. That of course zeroed optics. ICR recovered the beam. Attached is the final emittance scan. Slits are in at the 5mm positions.

That's it for 33S5+ development. I will switch off the source momentarily, and shut down the source gas supply.

As noted earlier, we have opened the OLIS cage and set up the source gases for 17O operation. It will take a while for the SO2 to pump away and for the 17O2 to equalize within the source body. Meanwhile, we have restarted the source with a preliminary 17O3+ beam on FC6. Without a doubt this will be unstable for a time, and the source may blink out also.

We completed 33S operation last night, and roughed in a setup for 17O. We had 17O3+ on FC6 overnight; chart attached. It grew nicely. Keerthi is working with the beam now.

Beam stayed up overnight nicely. Development today. RF scans in progress now.

Later... scanning done for the moment. Controls is looking at a PLC issue that has been on the books for a while. I have given the okay to turn on and off MCIS:IG1 at will.

Later aroun noon... We opened the cage and adjusted up the 17O2 flow slightly. Source is up and looking good. Optimize later.

Done for now. Some mass scans done. 1.2eµA at FC6.

Later... an initial emittance scan. Slits at 2.5mm.

Later... some tuning and another emittance scan. Slits at 5mm. 1.4eµA at FC6. EL deliberately low to balance skimmer spills. Save: 091104_1800.snapiosfc6

Let it cook for the night.

Beam was quiet overnight. Keerthi touched up the tune this morning, and it is quieter yet and a little more of it too.

Later... Handover to Sophia occurred as scheduled. Save: 091105_1203.snapiosdragon

An IOSIOC reboot occurred sometime over the lunch hour. The usual suspects went down, plus the field stability correction power supply went to its lower limit. Reset this 'n' that and we're back. ~2e˜µA at FC6.

Later... Latest save: 091105_1449.snapiosdragon

As noted, we handed over the beam to our users yesterday by noon. Setup to DRAGON is continuing. The report this morning that beam is great. Good.

Beam delivery continued through the weekend. As noted on Saturday, current dropped precipitously due to source gas pressure. We have 2.3e-6eµA this morning.

Beam ran well overnight. Last evening Vacuum Group diagnosed and repaired a catastrophic leak in the ILT cross region. You can see in the attached plot how venting that section caused elevated pressures in IOS, most likely due to the direction in which IOS:IV7 is installed. Most often it is the IOS section that is vented, and the neighbouring sections remain at high vacuum. So this gate valve would be installed looking downstream so that venting on the upstream side would tend to close the valve even harder. Yesterday was one of those rare times when the pressures were reversed, leaving only the spring tension of the valve maintaining vacuum in IOS. Pretty good, actually.

We are delivering a beam intensity exceeding the agreed rate. Intensity dropped off a little overnight, and it is pretty evident that it correlates with a higher vacuum in MCIS, suggesting that the 17O2 source gas flow has also dropped off. There is ample headroom presently, but the users may request a tweak after the energy change (in progress circa 09:00) and checks are complete.

Later... ICR requested a source tweak, which we did. A little increase.

Beam and energy changes continued over the weekend. The ICR reports that things are going swimmingly, and that the users are happy. Scaler counts are up some 30% or so from Tuesday. All good. A source and line touch-up Wednesday (Remembrance Day) morning and a tuning effort following an energy change during the day on Wednesday produced strong and stable beam running.

Attached is a stripchart of the last day or so of running. The thick blue trace is the DRAGON scaler. The fine green trace is a source collimator, representative of total beam from the source and its stability. The spikes are periodic Faraday cup readings.

DRAGON declared EOB at around 08:00 today. Source and beam were switched to 21Ne4+ for calibration studies.