Abstract
One of the important goals of the proposed future hbox {e}^{+}hbox {e}^{-} collider experiments is the search for dark matter particles using different experimental approaches. The most general search approach is based on the mono-photon signature, which is expected when production of the invisible final state is accompanied by a hard photon from initial state radiation. Analysis of the energy spectrum and angular distributions of those photons can shed light on the nature of dark matter and its interactions. Therefore, it is crucial to be able to simulate the signal and background samples in a uniform framework, to avoid possible systematic biases. The Whizard program is a flexible tool, which is widely used by hbox {e}^{+}hbox {e}^{-} collaborations for simulation of many different “new physics” scenarios. We propose the procedure of merging the matrix element calculations with the lepton ISR structure function implemented in Whizard. It allows us to reliably simulate the mono-photon events, including the two main Standard Model background processes: radiative neutrino pair production and radiative Bhabha scattering. We demonstrate that cross sections and kinematic distributions of mono-photon in neutrino pair-production events agree with corresponding predictions of the mathcal{KK} MC, a Monte Carlo generator providing perturbative predictions for SM and QED processes, which has been widely used in the analysis of LEP data.
Highlights
The search for dark matter (DM) particles is one of the main research goals of many running and planned experiments
We present results obtained for the neutrino pair production and for the Bhabha scattering, for the energy range from 240 GeV to 3 TeV, corresponding to the energy reach of the considered future e+e− collider projects: CEPC [10], FCCee [11], ILC [12] and CLIC [13]
Production of mono-photon events in e+e− collisions is considered as a possible signature for many Beyond Standard Model (BSM) scenarios
Summary
The search for dark matter (DM) particles is one of the main research goals of many running and planned experiments. The standard procedure to take ISR effects into account when generating events with Whizard is to use the builtin lepton ISR structure function which includes all orders of soft and soft-collinear photons as well as up to the third order in high-energy collinear photons This approach allows only for a proper modelling of the kinematics of the hard scattering, but is not suitable when we expect photons to be detected in the experiment. The ISR photon can be emitted by the incoming electron or positron, but for the process with the W± boson exchange, radiation is possible from the W± line, see Fig. 2 This is an additional argument to conclude that the standard approach to ISR photon generation, as implemented in Whizard, should not be used for detailed simulation of radiative neutrino pair production events. That is why a dedicated procedure for merging between the two regimes is needed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
