# The MSSM without Gluinos; an Effective Field Theory for the Stop Sector

## TL;DR

This paper develops an effective field theory for the MSSM focusing on the stop sector when gluinos and heavy squarks are much heavier, highlighting how parameter running differs from the full MSSM.

## Contribution

It introduces a new effective field theory framework for the MSSM that accounts for partial supersymmetry and integrates out heavy particles, providing modified parameter evolution.

## Key findings

- Sizable numerical differences between EFT and naive MSSM calculations.
- Modified running of parameters in the stop sector due to heavy gluino decoupling.
- Broken SUSY relations between parameters in the effective theory.

## Abstract

In this article we study the MSSM with stops and Higgs scalars much lighter than gluinos and squarks of the first two generations. In this setup, one should use an effective field theory with partial supersymmetry in which the gluino and heavy squarks are integrated out in order to connect SUSY parameters (given at a high scale) to observables in the stop sector. In the construction of this effective theory, valid below the gluino mass scale, we take into account $O(\alpha_3)$ and $O(Y_{t,b}^2)$ effects and calculate the matching as well as the renormalization group evolution. As a result, the running of the parameters for the stop sector is modified with respect to the full MSSM and SUSY relations between parameters are broken. We show that for some couplings sizable numerical differences exist between the effective field theory approach and the naive calculation based on the MSSM running.