Search for dark matter in events with a hadronically decaying vector boson and missing transverse momentum in pp collisions at √s=13 TeV with the ATLAS detector

• Main Author: Santos, S. P. Amor dos
• Publication Date: 2018
• Other Authors: Fiolhais, M. C. N., Galhardo, B., Veloso, F., Wolters, H., ATLAS Collaboration
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: https://hdl.handle.net/10316/107740; https://doi.org/10.1007/JHEP10(2018)180
• topic: Beyond Standard Model; Dark matter; Hadron-Hadron scattering (experiments)

A search for dark matter (DM) particles produced in association with a hadronically decaying vector boson is performed using pp collision data at a centre-of-mass energy of s=13 TeV corresponding to an integrated luminosity of 36.1 fb−1, recorded by the ATLAS detector at the Large Hadron Collider. This analysis improves on previous searches for processes with hadronic decays of W and Z bosons in association with large missing transverse momentum (mono-W/Z searches) due to the larger dataset and further optimization of the event selection and signal region definitions. In addition to the mono-W/Z search, the as yet unexplored hypothesis of a new vector boson Z′ produced in association with dark matter is considered (mono-Z′ search). No significant excess over the Standard Model prediction is observed. The results of the mono-W/Z search are interpreted in terms of limits on invisible Higgs boson decays into dark matter particles, constraints on the parameter space of the simplified vector-mediator model and generic upper limits on the visible cross sections for W/Z+DM production. The results of the mono-Z′ search are shown in the framework of several simplified-model scenarios involving DM production in association with the Z′ boson.