Upgrade of the Monte Carlo program BHLUMI for Bhabha scattering at low angles to version 4.04

Abstract
The new version of the Monte Carlo program for small-angle Bhabha scattering BHLUMI with an overall precision of 0.11% is presented. The main improvements are in the matrix element of the main multi-photon sub-generator based on the Yennie—Frautschi—Suura exponentiation, where the missing second-order terms in the leading-logarithmic (LL) approximation are supplemented and the contribution from the Z resonance is improved. In the LUMLOG sub-generator based on the LL approximation, we implemen...

Title of program: BHLUMI version 4.04
Catalogue Id: ACHI_v2_0 [ADFD]

Nature of problem
The small-angle Bhabha scattering process is used in all electron- positron colliders to calculate machine luminosity. This process is subject to QED radiative corrections, which have to be known for arbitrary cut-offs and/or acceptance with a precision at least a factor of 2 better than the pure experimental precision. This means that the level of 0.05% should be reached. A realistic simulation should include emission of the bremsstrahlung photons.

Versions of this program held in the CPC repository in Mendeley Data
ACHI_v1_0; BHLUMI version 2.01; 10.1016/0010-4655(92)90196-6
ACHI_v2_0; BHLUMI version 4.04; 10.1016/S0010-4655(96)00156-7

This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)