Precision sparticle spectroscopy in the inclusive same-sign dilepton channel at LHC

TL;DR

This paper proposes methods for precise measurement of sparticle masses in supersymmetry using the inclusive same-sign dilepton channel at the LHC, focusing on techniques that utilize only lepton momenta and total transverse momentum to improve accuracy.

Contribution

It introduces three novel inclusive techniques for measuring chargino and sneutrino masses that avoid jet-related uncertainties and combinatorics, enhancing precision in early LHC data.

Findings

Methods achieve high precision in mass measurements

Techniques are robust against jet measurement uncertainties

Applicable to early LHC supersymmetry searches

Abstract

The inclusive same-sign dilepton channel is already recognized as a promising discovery signature for supersymmetry in the early days of the LHC. We point out that it can also be used for precision measurements of sparticle masses after the initial discovery. As an illustration, we consider the LM6 CMS study point in minimal supergravity, where the same-sign leptons most often result from chargino decays to sneutrinos. We discuss three different techniques for determining the chargino and sneutrino masses in an inclusive manner, i.e. using only the two well measured lepton momenta, while treating all other upstream objects in the event as a single entity of total transverse momentum PT. This approach takes full advantage of the large production rates of colored superpartners, but does not rely on the poorly measured hadronic jets, and avoids any jet combinatorics problems. We discuss the anticipated precision of our methods in the early LHC data.