Search found 1924 matches

by michael_borland
07 Mar 2024, 17:00
Forum: Feature Requests
Topic: Modifications to find_aperture
Replies: 1
Views: 81

Re: Modifications to find_aperture

Mikhail, I think the only way you can get what I understand you are looking for is to use something other than line-search mode. By definition, line-search mode searches along lines starting from the origin. The radial spacing along the lines is xmax/nx. You can always reduce nx if you want finer st...
by michael_borland
19 Feb 2024, 10:32
Forum: Linac Tracking
Topic: issue tracking with PELEGANT
Replies: 6
Views: 142

Re: issue tracking with PELEGANT

Philippe,

The reason that happens in Pelegant is that the master processor is "non-working." It handles coordination among the slave processors, but (usually), doesn't do anything related to particle generation or tracking.

I'll add a check to the code for this problem.

--Michael
by michael_borland
15 Feb 2024, 18:03
Forum: Linac Tracking
Topic: issue tracking with PELEGANT
Replies: 6
Views: 142

Re: issue tracking with PELEGANT

Philippe, This command ~borland/improv/beta/Pelegant_2023.4 tracktest.ele > pElegantMichael.output looks wrong. Are you using mpiexec to invoke Pelegant? E.g., to run with 8 cores you'd use mpiexec -np 8 Pelegant ... It shouldn't be possible to run it any other way, but it is behaving as if it is us...
by michael_borland
15 Feb 2024, 17:38
Forum: Bugs
Topic: A bug in &save_lattice?
Replies: 2
Views: 109

Re: A bug in &save_lattice?

The problem is a typo in the definition of the quadrupoles. You have a spurious quotation mark at the end of the lines containing FSE values. This confuses the parser and it ignores the rest of the element definition.

--Michael
by michael_borland
09 Feb 2024, 11:41
Forum: Linac Tracking
Topic: issue tracking with PELEGANT
Replies: 6
Views: 142

Re: issue tracking with PELEGANT

Philippe, That is very weird. I don't see a problem with either the serial or the parallel version. I tried it on my linux workstation and Improv, with the latest source and version 2023.4. Are you using Improv? If so, check that you have the right modules loaded: $ module list Currently Loaded Modu...
by michael_borland
25 Jan 2024, 17:17
Forum: Linac Tracking
Topic: Beamline is unstable when matched=1 is set in twiss_output
Replies: 3
Views: 228

Re: Beamline is unstable when matched=1 is set in twiss_output

Wei Hou,

The basic problem is that a stable periodic solution will not always exist for arbitrary values of the cell parameters. You can set the quadrupole K1 values to something quite small (e.g., |K1|=0.001) to make it less likely that the initial conditions are unstable.

--Michael
by michael_borland
25 Jan 2024, 15:30
Forum: Linac Tracking
Topic: Beamline is unstable when matched=1 is set in twiss_output
Replies: 3
Views: 228

Re: Beamline is unstable when matched=1 is set in twiss_output

You can include the drift length as a variable in the optimization and then add an optimization term to make it equal the desired value.

See attached file.

--Michael
by michael_borland
25 Jan 2024, 11:19
Forum: General
Topic: Usage of computeRBGGE
Replies: 2
Views: 639

Re: Usage of computeRBGGE

Alex, Something is not right in construction of the magnet field map file. For example, if I plot By(x=0,y=0,z) using $ sddsplot -col=z,By magmnew.sdds -filter=col,y,-1e-6,1e-6 -filter=col,x,-1e-6,1e-6 -graph=sym I get plot-x0-y0.png Also, if try to plot By(x,y) as a function of z using $ sddssort m...
by michael_borland
25 Jan 2024, 11:05
Forum: General
Topic: ADTS calculation
Replies: 2
Views: 746

Re: ADTS calculation

As the manual states: "this command is deprecated, because it is too difficult to tune it to get reliable answers. The use of driving term computation in twiss_output is recommended instead, even though it doesn’t include all possibly relevant effects. For tune-spread calculations, the tune_footprin...
by michael_borland
25 Jan 2024, 10:20
Forum: General
Topic: field mapping by BMAPXY
Replies: 7
Views: 1316

Re: field mapping by BMAPXY

I converted small2.csv to SDDS. The range of data is quite small (+/-0.01mm), so there's hardly any room for the beam to move. Also, the grid is only 5x5, so the interpolation may not work well. Your data needs to cover the range of motion of the beam and have sufficient points in each dimension, e....