The OPAL Discussion Forum

[Philippe Piot <philippe.piot AT gmail.com>]

Also, I forgot to mention that setting FAST= TRUE does not affect the results. Best,  -- Philippe.

On Tue, Jan 18, 2022 at 5:42 AM Philippe Piot <philippe.piot AT gmail.com> wrote:

Dear All,

   I am using the 1DDynamic representation of an electromagnetic field for a gunf with the following block

1DDynamic 20 True
0 11.5 2999
185.79999999999998
0.0 2.0 199

1.0710e+07

... 2998 lines ...

1.9081e+04

when I track particles arranged on an initial grid I observe a modulation of transverse momentum as function position (see plot on the right below) while the use of a 3D map directly produced in omega3P give the expected dependency (left below). Could somebody comments if anything in my block above if wrong?

The call inside OPAL is as follows:

GUN: RFCavity, L = gun_len,
     VOLT = 40.0,
     ORIGIN = {0,0,0},
     TYPE = "STANDING",
     FMAPFN = "Ezvsz.dat",
     FREQ = gun_freq,
     LAG = (gun_inj_phase*Pi)/180.0;

 

Thank you very much. All the best,  -- Philippe.

px**2+py**2 (colormap) as function of x (horizontal) and y (vertical) axis obtained by tracking in a 3D map of the EM field (left) and with the 1DDynamic field map (right).