MieSimulator problem consulation

[hongxuekai]

Dear Janaka,

Hello!

I recently used Matlab to write a program about the Mie scattering phase function (hereinafter referred to as Matlab-Mie), and I encountered some problems during the test, so I would like to ask you for advice.

When comparing the results of Matlab-Mie and MieSimulator (hereinafter referred to as Mie-GUI), I found that there is a difference in the processing of the complex refractive index between the two. When the particle spectral distribution of the aerosol is the same, I input the complex refractive index m=1.41+0.007i in Mie-GUI, while in Matlab-Mie, I consider the effect of the atmospheric refractive index Nenv, and input the complex refractive index as m=1.41/Nenv + (0.007/Nenv)*i. However, this treatment results in a significant difference in the calculation of the scattering phase function between the two in the range of 160-180°, as shown in Fig1(a).

To further verify the problem, I set the imaginary part of the complex refractive index to 0, i.e., enter m=1.41+0i in Mie-GUI and m=1.41/Nenv+0*i in Matlab-Mie. At this point, the results of the aerosol scattering phase functions calculated by the two programs almost exactly coincide, as shown in Fig1(b).

Therefore, I would like to ask you, does the complex refractive index (m=x+ki) need to be divided by the atmospheric refractive index (Nenv) when calculating the Mie scattering phase function?

Looking forward to your reply and hope to get your professional guidance. Thank you!

[Annex: Charts for Fig1(a) and Fig1(b)]

	hongxuekai
hongx...@mail.dlut.edu.cn

[Janaka R]

Hello hongxuekai,

We considered the following sign convention (van de Hulst 1957).

msphere = mreal – j mimag

https://github.com/VirtualPhotonics/MieSimulatorGUI/wiki/Mie-Simulator-GUI-Running-Application

MieSimulatorGUI software already considered the minus sign.  To have a positive complex refractive index, you have to use m=1.41-0.007i in MieSimulatorGUI.

If your problem still exists, please let us know.

Best

Janaka

[hongxuekai]

Dear Janaka,

   I am writing to express my sincere gratitude for the assistance you provided in resolving the issue I had been facing. Your prompt response and comprehensive explanation were truly appreciated.

  The problem has now been successfully resolved, and I am relieved to have it behind me. Your knowledge and expertise in handling such matters were impressive, and I am glad to have had the opportunity to work with you.

  Once again, thank you for your help. I look forward to future collaborations and the chance to work with you again.

Best regards,

hongxuekai

	hongxuekai
hongx...@mail.dlut.edu.cn

---- Replied Message ----

From	hongxuekai<hongx...@mail.dlut.edu.cn>
Date	3/29/2024 00:15
To	virtual-photonics<virtual-...@googlegroups.com>
Subject	MieSimulator problem consulation