6.2 [35] generator, which provides matrix elements (ME) at NLO in the strong coupling constant αS, with the NNPDF3.1nlo [36] PDF set. The functional form of the renormalisation and factorisation scales was set to μr = μf = mT/4, where mT is defined as the scalar sum of the ...
All SM background MC processes were passed through the full ATLAS detector simulation [31] based on Geant4 [32]; samples for the BSM signal processes were simulated using the ATLAS fast simulation framework, ATLFAST-II, which uses parameterisations of electromagnetic and hadronic showers in the...
The hatched histograms denote the full event selection while the dashed histograms show the events at generator level that fall in the geometric acceptance (both the tracks are required to have |η| < 2.5 while the photon is required to have |ηγ| < 2.37, excluding the region 1....
the full ATLAS detector [49] based on Geant4 [50]. Only the MC samples describing SM tt¯tt¯ production and system- atic variations of the tt¯ simulation are processed through a faster simulation making use of parameterised showers in the calorimeters [51]. Additional simulated pp...
The innermost part of the ATLAS detector is the inner tracking detector (ID), which has full coverage in φ and cov- ers the pseudorapidity range |η| < 2.5. The ID is immersed in the 2 T axial magnetic field of a superconducting solenoid and measures the trajectories of charged ...
For all samples, a full simulation of the ATLAS detector response [50] was performed using the Geant 4 toolkit [51]. The effect of multiple interactions in the same and neighbour- ing bunch crossings (pile-up) was modelled by overlaying the original hard-scattering event with simulated ...