Model of Block et al.

References

[1]	​BLOCK, M. M., GREGORES, E. M., HALZEN, F. and PANCHERI, G., Phys. Rev. D60 (1999) 054024
[2]	​BLOCK, M. M., Phys. Rept. 436 (2006) 71-215

Implementation notes

Implemented in class BHModel (see in Doxygen).

There have been two issues discovered when implementing the model.

1. The definition of N_g is inconsistent between [1] and [2]. As confirmed in private communication with the authors, the correct normalisation is such that the average x carried by the gluons is 1/2 - which is the case of the value published in [1].
2. Using Eq. (478) from [2] does not give reasonable dsigma/dt. However, if a factor of 1/2 is applied to the r.h.s. (see BHModel::chi_without_i) the results overlap with the published predictions from the original authors (see a ​test sheet with Elegent calculations in green). It is possible that the 1/2 factor was omitted due to confusion with the other 1/2 factor mentioned in point 1.