bhcoat: Calculate the efficiency factors for coated spherical...
In AlexCast/rho: R Hydrology Optics

Description Usage Arguments Details Value References Examples

This function calculates the efficiency factors of extinction, absorption, scattering and backscattering for particle consisting of two concentric spheres.

1	bhcoat(ri, ro, ni, no, lambda)

`ri`	Radius of the inner sphere.
`ro`	Radius of the outer sphere.
`ni`	Refractive index of the inner sphere relative to surrounding medium.
`no`	Refractive index of the outer sphere relative to surrounding medium.
`lambda`	Wavelength in the surrounding medium, in the same units as the radius.

This function is a translation of the BHCOAT FORTRAN subroutine published by Bohren & Huffman (1983). Minor modifications were made, such as requiring refractive index and wavelength to be provided relative to the surrounding medium. The function should not be used for large, highly absorbing spheres and will issue a warning if input parameters describe this condition.

Note that all parameters must be scalars, while ni and no can be complex numbers. The refractive indexes should be relative to the surrounding medium (water) and lambda be in the same units as the radius of the concentric spheres.

A numerical vector with the efficiency factors for extinction, absorption, scattering and backscattering.

Bohren, C. F.; Huffman, D. R. 1983. Absorption and Scattering of Light by Small Particles. John Wiley & Sons, New York, 533 pp.

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ni  <-  complex(real = 1.02, imaginary = 0.006)
no  <-  complex(real = 1.10, imaginary = 0.0)
bhcoat(ri = 5, ro = 5.2, ni = ni, no = no, lambda = 0.675)