ImpactX
Public Attributes | List of all members
impactx::Quad_field_data Struct Reference

#include <SoftQuad.H>

Public Attributes

amrex::Vector< amrex::ParticleReal > default_cos_coef
 
amrex::Vector< amrex::ParticleReal > default_sin_coef
 

Detailed Description

Default Fourier coefficients

Fourier coefficients for the on-axis quadrupole field gradient k = 1/(Brho)*dBy/dx as a function of longitudinal position z. The default on-axis gradient is described by the function: k(z) = gscale/2*(tanh((z-zi)/g) - tanh((z-zf)/g)), where zf = -zi = L/2, L is the magnetic length of the quadrupole, and g is the full gap parameter. Here the parameters are chosen so that g/L = 1/10. This is based on a similar model used for soft-edge elements in MaryLie and ML/I, eg. http://www.physics.umd.edu/dsat/docs/MaryLieMan.pdf

This is equivalent to a single-parameter Enge model for the fields in the fringe region.

Usually superseded by user-provided input values.

Member Data Documentation

◆ default_cos_coef

amrex::Vector<amrex::ParticleReal> impactx::Quad_field_data::default_cos_coef
Initial value:
= {
0.834166514794446,
0.598104328994702,
0.141852844428785,
-0.118211272182381,
-9.056149864743113E-002,
1.803476331179615E-002,
4.464887700797893E-002,
7.364410636252136E-003,
-1.697541023436736E-002,
-9.012679515542771E-003,
4.367667630047725E-003,
5.444030542119803E-003,
-5.889959910931886E-005,
-2.409098101409192E-003,
-7.962712154165590E-004,
7.855814707106538E-004,
6.174930463182168E-004,
-1.340154094301854E-004,
-3.167213724698439E-004,
-4.925292460592617E-005,
1.221580597451921E-004,
6.331025910961789E-005,
-3.202416719002774E-005,
-3.872103053895529E-005,
8.212882937116278E-007
}

◆ default_sin_coef

amrex::Vector<amrex::ParticleReal> impactx::Quad_field_data::default_sin_coef
Initial value:
= {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0
}

The documentation for this struct was generated from the following file: