Note that I set Y amplitude to be ~149 units high. I did some quick trig based on the width vs height of the viewer circle and found that to be our goal for the Y amplitude if X is 130 units.
Are we sure that the picture in the procedure for the diagonal is correct? See Fig. 7-11, the result in figure 10 seems much more like what figure 5 in the procedure is indicating.
Fig. 1 shows orbit with V Wien at -90. After the jump I first tried adjusting the Wien magnet several hundred G-cm, but beam didn't show up initially so I set it back to the inital BDL. I went back and centered beam on ITV1I03 with the 1I03V corrector and found that beam was on the 1I04. Fig. 2-11 shows the viewer walk to 1D. Fig. 12 shows the orbit with the first tune mode I sent, and 13 the orbit corrected to 1D. I can't check interception as I don't have CW permissive, but beam doesn't look blown on the viewers. Doing this in increments of 5 degrees would have taken me a couple hours.
Let's see what happens with large adjustments! Queuing up Giant Steps by Coltrane and cranking the control room speakers to 11!
Cranked Wien magnet down about -40 G-cm to find it on 1I04 viewer, but no dice on the 1I05. Did a little dance between 0I02V, 0I03 V correctors and the Wien magnet to get it better centered on the 1I04 viewer. With these adjustment, beam was propagating all the way to the 0I01 viewer. Switching to tune mode to check things out and there's definitely some funny business with coupling when you make this big of a jump, but it's nothing I can't handle.
It seems to me, the most efficient procedure for Wien changes should go something like this:
1. Steer to PCup or FC1 using rels
2. Change Wien angle. Whether we need to use small increments or not should be discussed; this change was from -10 to -25, while the current procedure specifies that we should abide by 5 degree increments.
3. Flatten 1I04 or 1I07 BPMs with Wien magnet, perhaps pulling back some of this correction once beam is on the appropriate cup, and iterating between correction with the Wien magnet and the correctors directly upstream of it.
First tried adjusting the VWien directly from 0 to -25. I was able to steer very close to rels quite easily, but it seems the coupling was sufficient to confound the script (Fig. 2) as it just ended driving orbit farther from the rels. Starting from the top, I'm going to go from 0 to -25 in 5 degree increments on the V Wien.
Right off the bat, when changing from 0 to -5, the procedure would have us contact SMEs as the restored orbit (Fig. 4) is off more than 4.5 mm. The script has no way to flatten 1I04 positions, so we need to tweak those with the 1I03 correctors or the Wien magnet itself.
The following cavity histories have been updated:
2L21-6
Username: eforman
Date/Time: 01-18-26_20:22:45
RF Status: Bad
Tuner Status: Good
Comment: Excessive KMAI, OPS-PR'd
Special Instructions:
Maintenance Tag: Component: Operator Entry - See SME
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