eval_tidal_coeff
The eval_tidal_coeff tool evaluates one of a number of coefficients used in tidal expansions, as follows:
Label |
Symbol |
Description |
|---|---|---|
|
\(\cbar_{\ell,m,k}\) |
expansion coefficient for tidal potential |
|
\(\Gbar^{(1)}_{\ell,m,k}\) |
expansion coefficient for secular rate-of-change of longitude of periapsis |
|
\(\Gbar^{(2)}_{\ell,m,k}\) |
expansion coefficient for secular rate-of-change of semi-major axis |
|
\(\Gbar^{(3)}_{\ell,m,k}\) |
expansion coefficient for secular rate-of-change of eccentricity |
|
\(\Gbar^{(4)}_{\ell,m,k}\) |
expansion coefficient for secular rate-of-change of spin |
|
\(X^{-(\ell+1),-m}_{-k}\) |
Hansen coefficient |
|
\(\real[Y^{m}_{\ell}(\pi/2,0)]\) |
spherical harmonic at equator/prime meridian |
|
\(\real[Y^{m*}_{\ell}(\pi/2,0)]\) |
complex conjugate spherical harmonic at equator/prime meridian |
The full definitions of these coefficients can be found in Sun et al. (2023).
Syntax
Parameters
- coeff
Coefficient to calculate. For possible choices, see the label field in the table above.
- R_a
Ratio of stellar radius \(R\) to orbital semi-major axis \(a\)
- e
Orbital eccentricity \(e\)
- l
Harmonic degree \(\ell\)
- m
Azimuthal order \(m\)
- k
Fourier index \(k\)
Output
The coefficient is printed to standard output.