I created a cart-vol source. From the manual, i understood that centre of the box will be defined in first BEAMPOS card. In the next BEAMPOS card, the extension will be provided.
For example, in this attached image, the z center is at 148. My intension is to create the source with z from 126 to 170… (other x and y values are mentioned in the image).
Are these xin , xout etc values defined from this beam center mentioned in the first beampos card ? Or are they total length along x,y,z ??
To visualize this, I added one USRBIN card. In this regard, my doubt is
Does this USRBIN also follow the origin as the values given in first beampos card? Or are the values mentioned there defined with respect to origin of the system ? Because in my output, I could see plot for a zmin of around 135 instead of 120.
To define the source as isotropic, is it enough to keep delta phi as isotropic or do we have to change the ‘Type’ in BEAMPOS card ??
The out values should be the length of the edges of the volume, the in values are for the internal cavity of the volume, where no primary is generated (set to 0 if no cavity is needed).
The reason you don’t get what you expect is that you set Zout to 170 - (126 + 170) / 2 = 22, but is should be 170 - 126 = 44.
The Isotropic source direction has to be set on the BEAM card.
One more thing… For isotropic source, we have to choose isotropic in beam card in delta phi entry. But if we want to define direction as along positive z then we have to choose cos x = 0, cosy = 0 and type = positive in beampos, right ? In that case what should we use in delta phi in beam card? flat ??
on the BEAMPOS card you can set the direction (and position) of the beam. On the BEAM card with the DeltaPhi you can set the divergence from the set direction.
If your divergence is zero then you can leave DeltaPhi empty and it doesn’t matter if you select Flat or Gauss.
By the way, the option Isotropic is just a shorthand for an divergence angle greater than 2*Pi with Flat distribution, as you can see in the .inp file.
