EGSnrc multiple scattering look-up table

[KlaasWillems]

Hi,

I've been going through the EGSnrc documentation[1]. For my work, I need to sample the multiple scattering distribution based on the screened Rutherford cross-section. The algorithm for this is given in section 2.4.8.i of [1] and involves working with the look-table newms.data, which I found here under a slightly different name. I have several questions regarding this look-up table.

1. From my understanding of the init_ms_SR routine, the newms.data file contains four lookup tables: ums_array, fms_array, wms_array and ims_array. Which of these contains the multiple scattering distribution q_SR^{2+}? Having looked at the code, I assume it is ums_array, however, could someone confirm?
2. ums_array is three-dimensional (64x8x32). Could you confirm the first dimension corresponds to the ln(\lambda) and the second to G_{1, SR} (notation from section 2.4.8.i in [1])? Having plotted the data, I assume the third dimension is the q_{SR}^{2+} distribution given as a cumulative probability distribution. Is this correct?
3. For which values of ln(\lambda) and G_{1, SR} was the look-up table generated?

Kind regards,
Klaas

[1] The EGSnrc Code System: Monte Carlo Simulation of Electron and Photon Transport - Kawrakow et al.

[rtownson]

Maybe this is something @eric11210 looked at somewhat recently?

[eric11210]

Sorry @rtownson, for some reason I didn't note that I was mentioned here.

@KlaasWillems, unfortunately I haven't into this at all, so I don't have any answers for you anyway.