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Appendix A: Coefficients in the equations

The coefficients that appear in Eq. (31) can be computed with the help of a symbolic computation program. These coefficients turn out to be rather cumbersome quotients of polynomic expressions in our model with uniform twist, (A.1)(A.2)(A.3)(A.4)Next, we can compute the coefficients in Eq. (33), (A.5)(A.6)Then, the coefficients that appear in the boundary conditions (Eq. (56)) are given by (A.7)(A.8)The coefficients that appear in the thin tube limit for the differential equations (Eqs. (57), (58)) can be cast as (A.9)(A.10)

The coefficients for the boundary conditions suitable for analytical solution (Eq. 65), which also appear in the dispersion relation (Eq. 66), are (A.11)(A.12)Finally, the coefficients that appear on the sixth-order algebraic equation (Eq. 69) for m > 0 are

(A.13)

© ESO, 2011