7.19 coupled_twiss_output

&coupled_twiss_output  
    STRING filename = NULL;  
    long output_at_each_step = 0;  
    long emittances_from_twiss_command = 1;  
    double emit_x = 0;  
    double emittance_ratio = 0.01;  
    double sigma_dp = 0;  
    long calculate_3d_coupling = 1;  
    long verbosity = 0;  
    long concat_order = 2;  
&end

This feature was added to elegant using code supplied by V. Sajaev, based on Ripkin’s method. The code computes the coupled lattice functions, then uses the supplied emittance, emittance ratio, and momentum spread to compute the beam sizes, bunch length (if rf is included), and beam tilt.

divide_elements