SFITTER: SUSY Parameter Analysis at LHC and LC

TL;DR

The paper presents SFITTER, a grid+fit framework for extracting weak-scale MSSM parameters from collider data, capable of handling correlations and combining multiple data sources. It first demonstrates parameter determination within mSUGRA/cMSSM using SPS1a data, highlighting precision in m0 and m1/2 but weaker sensitivity to tanβ and A0. It then extends to the general MSSM with 24 parameters, showing that a grid-initialized fit can recover most parameters from masses alone, though some (Aτ, Ab) require additional observables. Across toy studies, the synergy between LHC and LC measurements proves crucial for a nearly complete, model-independent mapping of the weak-scale MSSM, underscoring the value of joint analyses and grid+fit strategies.

Abstract

SFITTER is a new analysis tool to determine supersymmetric model parameters from collider measurements. Using the set of supersymmetric mass measurements at the LC and at the LHC we show how both colliders probe different sectors of the MSSM Lagrangian. This observation is a strong motivation to move from a parameter fit assuming a certain model to the unconstrained weak-scale MSSM Lagrangian. We argue how the technical challenges can be dealt with in a combined fit/grid approach with full correlations.