2.3.1. PWFA¶

class scisalt.PWFA.Ions(A, N_e, sig_r, sig_xi, r0_big=None, n_samp=1000, order=5)[source]¶

New in version 1.6.

A class to facilitate calculating ion motion in PWFA ion columns due to cylindrical, infinitely-long gaussian beams.

A¶: Ion mass in units of AMU

N_e¶: Number of electrons in bunch

k¶: Driving force term: $r'' = -k \left( \frac{1-e^{-r^2/2{\sigma_r}^2}}{r} \right)$

k_small¶

Small-angle driving force term: $r'' = -k_{small} r$ .

Note: $k_{small} = \frac{k}{2{\sigma_r^2}}$

lambda_large(r0)[source]¶: The wavelength for large ( $r_0 < \sigma_r$ ) oscillations.

lambda_small¶: The wavelength for small ( $r_0 < \sigma_r$ ) oscillations.

m¶: Ion mass

omega_big(r0)[source]¶

r(x, r0)[source]¶: Numerically solved trajectory function for initial conditons $r(0) = r_0$ and $r'(0) = 0$ .

r_large(x, r0)[source]¶: Approximate trajectory function for large ( $r_0 > \sigma_r$ ) oscillations.

r_small(x, r0)[source]¶: Approximate trajectory function for small ( $r_0 < \sigma_r$ ) oscillations.

sig_r¶: Transverse R.M.S. width

sig_xi¶: Longitudinal R.M.S. width

class scisalt.PWFA.Match(plasma, E, emit_n)[source]¶

Given a plasma of type Plasma and a beam of energy E in GeV and normalized emittance emit_n in SI units, calculates match parameters

beta(E)[source]¶: $\beta$ function of matched beam

emit_n¶: Emittance of beam

gamma¶: Relativistic $\gamma$ of beam

sigma¶: Spot size of matched beam

class scisalt.PWFA.Plasma(n_p=None, n_p_cgs=None)[source]¶

A class for relating plasma density to plasma frequency $\omega_p$ and ion focusing force.

Input either:

Plasma density n_p in SI units
Plasma density n_p_cgs in CGS units

k_ion(E)[source]¶: Geometric focusing force due to ion column for given plasma density as a function of E

n_p¶: Plasma density in SI units

n_p_cgs¶: Plasma density in CGS units

w_p¶: Plasma frequency $\omega_p$ for given plasma density