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Topic: Projection of isotropic 3D radiation on flat screen
Replies: 1   Last Post: Nov 20, 2012 1:16 PM

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 machiel Posts: 8 Registered: 11/20/12
Re: Projection of isotropic 3D radiation on flat screen
Posted: Nov 20, 2012 1:16 PM

To answer my own question.
From the point source to the nearest point on the screen is distance r1. This is a vector lying on a sphere with area (4 pi r1^2). The density of vectors on this sphere is N/(4 pi r1^2).
For a point further on the screen, the vector from the point source is distance r2. The density of vectors on this sphere is N/(4 pi r2^2).
Density_2 / Density_1 = r1^2 / r2^2 < 1.
This will give you the density of the flux on any point of the screen.

On Tuesday, November 20, 2012 4:21:09 PM UTC+1, machiel wrote:
> Hi,
>
>
>
> When I have an isotropic point-like source that radiates isotropically in 3-D space, how can I calculate the number of events that reach a screen a
>
> certain distance away, with the probability as a function of (transversal) x and/or y on that screen.
>
> Hence, I want to know how to derive a function for the amount of events that reach a certain region on a flat screen, when the origin of these events is some isotropic point-like source.
>
> Any help would very much be appreciated.
>
> Best regards,
>
>
>
> Machiel

Date Subject Author
11/20/12 machiel
11/20/12 machiel