The following are outputs from Transport and Revmoc runs on M13. I'll replace this with a more polished version when I get a chance.

Transport and Revmoc tunes for M13

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As I understand it, there are approximately three ways to tune the muon beam to get particles across the fringe field.

1. parallel rays incident upon the fringe field
2. rays focused to a point at the fringe field
3. rays which come in at a tangent to the fringe field lines.

I am able only to look at the first two of the above using Transport and Revmoc. I'm not an expert on either, but I believe that I have a code which includes the a fringing of the entrance field, but which has no fringe field at the exit. This allows for the consideration of rays which stop inside of the solenoid.

The basic conclusions (which can be gleaned from the following figures) are that:

1. M13 can be tuned to give parallel rays, at the expense of making the beam very large. This is shown with the solenoid off in the first figure.
2. When the solenoid is turned on, these parallel rays diverge due to the interaction with the fringe field. This is shown in Figure 2.
3. A focused beam, with no solenoid, is shown in Figure 3.
4. These rays can be brought nearly parallel by tweaking the focus and turning the solenoid on. This is shown in Figure 4.
5. Figures 5 - 11 refer to the tune of figure 4, and are results of Revmoc simulations. Figure 5 shows the spatial distributions and the divergence for muons at the axis of the detector. The "trigger" refers to a sweet spot 1cm square at the center of the detector.
6. In figures 6-7 I try to find the origination of the good muons upstream of the detector. The distributions at the JAWS don't really help.
7. Divergence at JAWS.
8. There is some spatial (vertical) discrimination at the TEC, as shown in figure 8.
9. Divergence at TEC.
10. Divergence at the Trigger
11. Figures 11-13 show similar distributions for parallel rays tracked across the fringe field.

My conclusions:

The above distributions look similar for either the focused or the parallel tune brought across the fringe field. The flux appears to be slightly better for parallel rays incident upon the fringe field.

This does not argue against the possibility of an "adiabatic transition" across the fringe field.

The rates are:

Focused tune: 1.6x10^-4 = (806 Good Muons) / (5 x 10^6 Generated Muons)

Parallel tune: 1.93x10^-4 = (694 Good Muons) / (3.6 x 10^6 Generated Muons)

Where the normalization is to the total particles generated into the REVMOC phase space (darn… I'll need to check on the momentum distribution which was used if anyone wants to try to convert this into a real fllux) which is defined by

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