"beamline unstable" problem
Posted: 27 Feb 2015, 12:18
Dear Michael,
I'm simulating the focusing of an ultra-short electron bunch for plasma injection, in LWFA .
The beam emittance in really low (0.2e-6 m, for 15pC of charge). It's a cylindrical beam and it's envelope is 1 mm and Ss = 4.2e-6 m.
The tracking of this beam, by using ASTRA, doesn't give any problem. Now I'm trying to optimize the focusing channel, for the plasma injection, by using a triplet; Elegant replies "warning: beamline unstable for y plane--can't match beta functions." (Using only a drift the error is "Unable to compute dispersion: unstable").
The problem is that with this error it's not possible to perform the optimization that I'm trying to do.
If you belive that the problem lies in the bunch
Thank you in advance for your precius help
Marcello
I'm simulating the focusing of an ultra-short electron bunch for plasma injection, in LWFA .
The beam emittance in really low (0.2e-6 m, for 15pC of charge). It's a cylindrical beam and it's envelope is 1 mm and Ss = 4.2e-6 m.
The tracking of this beam, by using ASTRA, doesn't give any problem. Now I'm trying to optimize the focusing channel, for the plasma injection, by using a triplet; Elegant replies "warning: beamline unstable for y plane--can't match beta functions." (Using only a drift the error is "Unable to compute dispersion: unstable").
The problem is that with this error it's not possible to perform the optimization that I'm trying to do.
If you belive that the problem lies in the bunch
Thank you in advance for your precius help
Marcello