Search for scalar leptoquarks and T-odd quarks in the acoplanar jet topology using 2.5 fb-1 of ppbar collision data at sqrt(s)=1.96 TeV

TL;DR

This paper reports a search for new particles, scalar leptoquarks and T-odd quarks, using collider data, setting mass limits and finding no significant deviation from the standard model in the acoplanar jet topology.

Contribution

It provides new lower mass limits for scalar leptoquarks and T-odd quarks based on analysis of 2.5 fb-1 of collider data, extending previous constraints.

Findings

No excess events observed beyond standard model predictions.

Set a lower mass limit of 205 GeV for scalar leptoquarks.

Derived limits on T-odd quark masses as a function of T-odd photon mass.

Abstract

A search for new physics in the acoplanar jet topology has been performed in 2.5 fb-1 of data from ppbar collisions at sqrt(s)=1.96 TeV, recorded by the D0 detector at the Fermilab Tevatron Collider. The numbers of events with exactly two acoplanar jets and missing transverse energy are in good agreement with the standard model expectations. The result of this search has been used to set a lower mass limit of 205 GeV at the 95% C.L. on the mass of a scalar leptoquark when this particle decays exclusively into a quark and a neutrino. In the framework of the Little Higgs model with T-parity, limits have also been obtained on the T-odd quark mass as a function of the T-odd photon mass.