Backscattering vs scattering

[nicodemoor]

Hello,

I've found something weird when I compare the backscattering efficiency and the scattering efficiency of gold particle (50nm=R).

The former is higher than the last which I think could not be possible!

What's wrong?

Here the code :

` import PyMieScatt as ps from Mie2 import Miedata import matplotlib.pyplot as plt from numpy import array md = Miedata("Au")

wvl,n,k = md.indice()

m = n + k*1j

Qext_list = [] Qsca_list = [] Qabs_list = [] g_list = [] Qpr_list = [] Qback_list = [] Qratio_list = []

print(len(wvl))

for i in range(len(wvl)): [Qext,Qsca,Qabs,g,Qpr,Qback,Qratio] = ps.AutoMieQ(m[i],wvl[i],50,1.33,asCrossSection=False)

Qext_list.append(Qext)
Qsca_list.append(Qsca)
Qabs_list.append(Qabs)
g_list.append(g)
Qpr_list.append(Qpr)
Qback_list.append(Qback)
Qratio_list.append(Qratio)

plt.plot(wvl,Qratio_list,label="Qratio") plt.plot(wvl,array(Qback_list)/array(Qsca_list),"--",label="calculate") plt.plot(wvl,Qback_list,label="Qback") plt.plot(wvl,array(Qsca_list)array(Qratio_list),"--",label="QscaQratio") plt.plot(wvl,array(Qsca_list),".",label="Qsca") plt.ylabel("Q") plt.xlabel("Wavelength (nm)") plt.legend() plt.show()

`