Elegant users forum

Dear Elegant developers,

My name is Vladimir Kornilov, I am an accelerator physicist at GSI Darmstadt, Germany.

I am using elegant for beam tracking simulations for our synchrotrons, with the effects of magnet errors and especially effects of high-intensity, space-charge.

My question is about the implementation of values of N, sigma_x, sigma_y and sigma_z in the formulas for space-charge:
https://ops.aps.anl.gov/manuals/elegant ... 0500010.90

Are these fixed values from the input file, or are they recalculated during the bunch tracking?

Is it possible to keep these values constant? Or averaged over certain number of turns (for slow processes)?

The issue which I detected is the unstable behavior (beam losses) due to space-charge kicks. These losses decrease for higher number of particles "n_particles_per_bunch". I think this maybe because of fluctuations of emittances due to field errors, and thus fluctuations in space-charge kicks.

Thank you, and
Best regards,
Vladimir

Vladimir,

The beams sizes are computed turn-by-turn from the particle distribution. At present, there is no option to use fixed sizes or averaged sizes, but adding that is a good idea. I'll try to get it in the next release.

Meanwhile, using Pelegant will allow running with more particles without excessive run times.

--Michael