How can I accurately plot the Bragg curve for alpha particles?

[naiveBen]

it`s needless to say that dx is supposed to be really small amount.

but i need some reasonable clue.. let me know why it has to be 0.01 or something..

T^T

 

[spenmurphy]

Thank you very much Bob. You've been very helpful. I don't have Truebasic, so I write your code in Excel worksheet.

What did this code look like? I'm just learning how to use Excel VBA.

Thanks!

 

[ekosulistya]

naiveBen,
did you mean that it has to do with the free path length of the ion? I think, dx in the equation is a small step the ion make, whatever the interaction that has happened to the ion, and in any direction. it's computational step, the smaller step we choose, the graph is more smooth.

spenmurphy,
I wasn't using VBA Excel, but worksheet formula only. You can see the snapshot of part of the worksheet in my previous message. I rewritten the code from Bob in worksheet cell, step by step, copy all the way down, and the result is a data set, from which we can choose the value of x and dE/dx, and plot it with Excel scatter chart

 

[Moho]

In case anybody is still around, I have a question about the Bragg curve for alpha particles. I was able to follow Bob S's code above (albeit in Excel) and I get a good result, but I notice that energy (E, not dE/dX) never goes to 0. The alpha particle still seems to have a lot of energy (~0.18 MeV) even after it has traversed its stopping distance. Does this make physical sense? What could be wrong? I'm a PhD geology student but my physics is at undergraduate level so I'm a bit confused.