Zero score in some bins

Dear Experts,

rotdef.flair (4.0 KB) rotdef_1E07,1cycle.lis (3.5 KB) rotdef_2E07,1cycle.lis (3.5 KB) rotdef_8E06,1cycle.lis (3.5 KB) rotdef_9E06,1cycle.lis (3.5 KB)

Regarding Cartesian binning: zero score in few bins - the simulation was Run for a No. of primaries, say X, 1 cycle: Scoring in successive bins was obtained but few bins, in between, score ‘zero” values with ‘zero’ statistical error.
On increasing the no. of primaries, say Y (>X) I observed that the no. of bins scoring ‘zero’ have reduced but still one or more score ‘zero’.

Now, the question is: is this ‘zero’ score in between somewhere implies incorrectness of my input (because photon disappearing suddenly and then appearing again doesn’t seem logical ??) or I should keep on increasing no. of primaries to get a finite score in all the bins (yes, with 99 % statistical error, as it is 1 cycle) and then Run the simulation with good no. of cycles to reduce the statistical value to an acceptable value ?

Please find attached the input and .lis files for increasing number of primaries to show what I said above. (Zero scores in USRBIN “4 DERear1m”). Surprisingly, USRBIN “2 DEFron1m” scores values in all the bins. I don’t understand why this is happening ? The source is isotropic.
Kindly advise.

Thanks and regards,

Dear Raksha,

it seems to me that the location – the x coordinates – of the DERear1m scoring is incorrect, thus you don’t get what you expect.