Search for dark matter in the mono-lepton channel with pp collision events at center-of-mass energy of 8 TeV

A search for new physics in final states with an electron or a muon and a neutrino has been performed and is documented in EXO-12-060. The results can be interpreted in terms of the cross section of a W-boson recoiling against a pair of dark matter particles in an effective theory. Such process would be visible in the detector as a lepton + $E_{\mathrm{T}}^{\mathrm{miss}}$ final state. The dark matter model consideres two possible couplings, vector- and axial-vector like. They could couple to up- and down-type quarks with different strengths, parametrized by $\xi$. Possible consequences on the signal cross section and shape are studied. The results are presented in terms of production cross section limits, which are transformed to limits on the effective parameter $\Lambda$ and $M_{\chi} $-proton cross sections as measured by the direct detection experiments. The limits derived on $\Lambda$ are $\Lambda<$1000/700/300\GeV for $\xi$=-1/0/+1, for both vector and axial-vector coupling.