By email from JHC¶

On 15/09/17 09:25, John Cobb wrote:

Can't be at the meeting, but perhaps you could pass on the following thought for a sanity check / clean up for the field-off analysis.

It should be possible, given the up and downstream track vectors and a bit of simple algebra, to determine the approximate position of the scattering. This will be at the Z where the distance between the two extrapolated tracks is minimum.

Sanity checks would be that this Z is in the absorber, and that the minimum distance between the up and downstream tracks is sensible. And so on.

This may or may not tell us anything, but it would be interesting to look. Pathological bad cases could be excluded.

Just an idea, but it's something I would do.

Could / should also be done for field on.

Cheers,

jhc

It's a good thought. A related (possibly same) thing that DK and others have suggested is to extrapolate the tracks back and check that upstream and downstream hit the same position at the absorber.

Cheers,
Chris