Search for dark matter particles in proton-proton collisions at sqrt(s) = 8 TeV using the razor variables

TL;DR

This paper reports a search for dark matter particles in proton-proton collisions at 8 TeV using the CMS detector, employing razor variables to analyze jet events and setting limits on dark matter production.

Contribution

It introduces the use of razor variables in dark matter searches at the LHC, providing complementary results to previous analyses.

Findings

No significant excess observed over background.

Dark matter production is excluded at 90% CL for mediator mass below 1 TeV.

Razor variables effectively discriminate signal from background.

Abstract

A search for dark matter particles directly produced in proton-proton collisions recorded by the CMS experiment at the LHC is presented. The data correspond to an integrated luminosity of 18.8 inverse femtobarns, at a center-of-mass energy of 8 TeV. The event selection requires at least two jets and no isolated leptons. The razor variables are used to quantify the transverse momentum balance in the jet momenta. The study is performed separately for events with and without jets originating from b quarks. The observed yields are consistent with the expected backgrounds and, depending on the nature of the production mechanism, dark matter production at the LHC is excluded at 90% confidence level for a mediator mass scale Lambda below 1 TeV. The use of razor variables yields results that complement those previously published.