[Mott] Status update .... t-minus one and counting.

[Joseph Grames]

Status update...

1. Last night Yan corrected the chopper 1 issue and a nice setup prevails.

2. Offline I looked at the beam energy setup from two nights ago.  Using dipole and stray (earth/corrector field) models the measured and predicted beam positions using two opposing spectrometers (2D and 5D) agree at ~0.1% level.  This value is subject to assumptions that can be improved later, but I believe we known the KE <1%, likely much better.

3. On Friday we'll lock-up INJ/NL as soon as possible, recover beam to FC2, then Mott to set the spin rotators, and finally set/test the KE=5.0 MeV Mott setup.  Then we do beam emittance and energy spread measurements.

4. Upcoming shifts look like this:
Fri DAY (Joe/Matt)
Fri SWING (Marcy/Tim) - high probability of 0L03 background
Sat OWL (Riad/Daniel) - medium probability of 0L03 background
Sat DAY (Joe/Marty) - small probability of 0L03 background until end of Run II

5. The three priority measurements are:
a) elastic rate @ KE=5.0 MeV (10 good foils, <0.5 shift)
b) asymmetry & momentum measurement v. gradient (5 settings attached, 0.35/1.0 um Au, 0.25% stat, ~2 shift)
c) asymmetry v. thickness @ KE=5.0 MeV (1 energy, 10 good foils, 0.25% stat, ~3 shift)

6. Charlie, have a good trip!

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