160
10
10
14
10
~(e)
12
10
10
10
8
10
•
10
4
10
2
10
0
10
-2
10
-4
10
-.
10
108
r~
_10 1
10
90'
120
150
180
30
60
e
Figure 4. Volume scattering functions, {1 (0), computed through Mie theory when the index of refraction is real
(n = 1.05) and the size parameter a is given successive values of 0.1, I, 10, 100, 1000 and 10000
(curves from bottom to top). The numerical values of (1(0) (dimension m" sr") are internally consistent,
albeit arbitrary (because the wavelength is not fixed).
In Figure 4 shows the volume scattering functions (VSF) computed through Mie theory for
a single spherical particle with a real relative index n = 1.05 (no absorption) and with
increasing values given to the size parameter a (namely 0.1, 1, 10, 100, 1000, 10 000). If
the wavelength is assumed to be 421 nm, it comes ex = 10 d, so that the corresponding sizes
range from 0.01 to 100 ILm. Two important features emerge from this figure: i) the shape of
the VSF is symmetrical with respect to the scattering angle q = 90° only in the Rayleigh
domain (when ex = 0.1 and p = 0.01), and departs from symmetry by the progressive