A search is presented for production of dark-matter particles recoiling against a leptonically decaying Z boson in 20.3fb-1 of pp collisions at s=8TeV with the ATLAS detector at the Large Hadron Collider. Events with large missing transverse momentum and two oppositely charged electrons or muons consistent with the decay of a Z boson are analyzed. No excess above the Standard Model prediction is observed. Limits are set on the mass scale of the contact interaction as a function of the dark-matter particle mass using an effective field theory description of the interaction of dark matter with quarks or with Z bosons. Limits are also set on the coupling and mediator mass of a model in which the interaction is mediated by a scalar particle. © 2014 CERN, for the ATLAS Collaboration.
Aad, G., Abajyan, T., Abbott, B., Abdallah, J., Abdel Khalek, S., Abdinov, O., … Zwalinski, L. (2014). Search for dark matter in events with a Z boson and missing transverse momentum in pp collisions at s =8TeV with the ATLAS detector. Physical Review D - Particles, Fields, Gravitation and Cosmology, 90(1). https://doi.org/10.1103/PhysRevD.90.012004