Momentum Compaction Not Calculated when Lattice is below Transition

[henrylovelace3]

Why is show universe giving a negative momentum compaction value?

If we calculate the value the simple way, the value is clearly positive. Normal form is also not consistent.

Normal form is also not consistent.

Attach is the lattice file.

error.zip

[DavidSagan]

Looks like the calculation makes a high energy approximation. I am working on a fix.

[DavidSagan]

I have put in a fix.

[henrylovelace3]

@DavidSagan Thanks I see it. Is the lat::momentum_compaction[] linked to the value shown from the universe table?

[DavidSagan]

Should be.

On Jan 25, 2023, at 7:09 PM, henrylovelace3 @.***> wrote:

@DavidSaganhttps://github.com/DavidSagan Thanks I see it. Is the lat::momentum_compaction[] linked to the value shown from the universe table? [image]https://user-images.githubusercontent.com/30727946/214722376-2ef5b0a1-0aa3-4285-b0e9-41e1a7b40d9b.png

— Reply to this email directly, view it on GitHubhttps://github.com/DavidSagan/Bmad/issues/324#issuecomment-1404384016, or unsubscribehttps://github.com/notifications/unsubscribe-auth/AAH2PVULQ4XW5AZPG2NILLDWUG6EBANCNFSM6AAAAAAUEJOO6M. You are receiving this because you were mentioned.Message ID: @.***>

[henrylovelace3]

In the png is there two values are very different @DavidSagan

[henrylovelace3]

@DavidSagan I also noticed that lat::rad_int.i1[end]|model does not update even though the lattice model changes

The two numbers do not need to agree but what to notice is that 1: does not change with the change in the dispersion of the lattice.

[DavidSagan]

OK will reopen and have a look...