x-slice energy spread

[Jafarinia]

Hi Michael,

I am trying to reduce the x-slice energy spread at the end of the beam line. I am using dipole to disperse the beam but due to the beam large energy spread (or any other reason) the x-slice energy spread is too large for the TGU. I am using sextupole to reduce transverse emittances and getting linear chirp (x-p). I have attached the final x-p phase space. I am not sure that it is the best way to reduce the x-slice ES. I was wondering if there is another way to do that.

Thanks,
Farzad



Farzad

[michael_borland]

Farzad,

If I understand the problem, you are ideally hoping to produce a p-x distribution that is a thin line. This means that anything other than the linear dispersion needs to be negligible at the observation point. That suggests making sigma matrix elements like s12 as small as possible. That could mean small emittance or large betax, or both in some combination. Also, making the dispersion large will help. You can also try to restrain second order matrix elements such as T162 and T166.

--Michael