transmission diffraction

In my experimental simulation graph, the central position cannot be as large as in the experimental data graph. I suspect this may be due to transmission. Is it possible to make adjustments in the software to address this issue? Or do you have any other suggestions to make it closer to reality? Thank you.

Dear Wei,

Do you mean peak intensity value or spot size on the detector array?

Dear Mikhail,

I mean spot size on the detector array.

In my experience, the shape of the reflected beam is determined partly by the original intensity profile and partly by the beam divergence curve. Estimation of contribution weights requires knowledge of the experimental conditions.

For the time being it would be better to exclude near-specular area from fitting by applying masks

But it shouldn't be related to the transmitted intensity.

Are you suggesting that I should ignore the central part? Or do you have any other suggestions? Thank you.

Currently BornAgain addresses the intensity of specular peak according to polar and azimuthal beam divergence. The beam itself is "thin" before the divergence, there is no internal intensity profile. That is why the good match of measured and simulated data is unlikely to expect. For that reason the area selected black is not of high importance for the analysis with BornAgain.

Nevertheless, you can set polar(grazing) angle distribution to Gauss or Lorenz and see how it changes the observable result.

I see, thank you very much. So, should I also disregard the halo indicated by the black arrow? 圖片1

By the way, My grazing angle is already Gaussian distributed.! 螢幕擷取畫面_2023-09-12_172017

To my knowledge, such galo is presumably related to diffuse scattering from sample or its environment. So it shouldn't be neglected by default unless you want to focus on other features of scattering pattern.

Then Gauss decays too quickly, more long-tailed distribution like Lorentzian can lead to another observable behavior.

added instrument & resolution r&t user request labels

Dear Wei, I hope Mikhail's explanations were somehow helpful for you. I will now close this issue. For further questions and suggestions you are always welcome to open a new issue or write to contact@bornagainproject.org.

closed