[Gate-users] Strange Dose Profiles

[Ashok Tiwari]

Hi Chris, 

First, it would be easy for us if you copy-paste the part of your macro instead of attaching images.

Size of the dose actor is different than the size of the spherical phantom (say target according to your macro), but you have to set the size of actor (setSize parameter) is equal to size of sphere, so that you can store all the dose informations up to the boundary of the sphere. Therefore, diameter of spherical volume would be equal = Resolution of matrix * voxel size. In other words, setSize of dose actor = resolution * voxel size.

Yes, we need to attach dose actor to the center of spherical volume. You did it correctly. 

Your dose actor seems ok. Now, you can check:
1. the radius of the sphere, I suggest you to put 125 mm as its radius (0.5*500=250, 250/2=125)
2. Source: use discrete spectrum of P-32 beta emitter
3. You may want to save your dose matrix at every 60 seconds instead 20 to lessen the simulation time
4. One more important thing: if you want to have particle interaction in each voxel volume (many authors defined this volume as a dosel) then set step size as 0.5 mm and activate the step limiter parameter. 

Try these things, if these does not work then send me your main macro, I will take a look.

Thanks, 
Ashok