[Paper Review] Precision calculations in the MSSM Higgs-boson sector with FeynHiggs 2.14

Henning Bahl, Thomas Hahn+5 more|arXiv (Cornell University)|Nov 22, 2018

Particle physics theoretical and experimental studies207 references107 citations

TL;DR

The paper updates FeynHiggs to version 2.14.3, detailing improved fixed-order and EFT calculations for MSSM Higgs masses, along with code structure enhancements.

ABSTRACT

We present an overview of the status and recent developments of FeynHiggs (current version: 2.14.3) since version 2.12.2. The main purpose of FeynHiggs is the calculation of the Higgs-boson masses and other physical observables in the MSSM. For a precise prediction of the Higgs-boson masses for low and high SUSY scales, state-of-the-art fixed-order and effective-field-theory calculations are combined. We first discuss improvements of the fixed-order calculation, namely an optional $\\overline{\ ext{DR}}$ renormalization of the stop sector and a renormalization of the Higgs sector ensuring the chosen input mass to be equivalent with the corresponding physical mass. Second, we describe improvements of the EFT calculation, i.e. an implementation of non-degenerate threshold corrections as well as an interpolation for complex parameters. Lastly, we highlight some improvements of the code structure easing future extensions of FeynHiggs to models beyond the MSSM.

Motivation & Objective

• Provide an overview of the current status and recent developments of FeynHiggs since version 2.12.2.
• Describe improvements in fixed-order calculations, including DRbar renormalization and Higgs-sector renormalization.
• Describe improvements in EFT calculations, including non-degenerate threshold corrections and complex-parameter interpolation.
• Explain code-structure improvements aimed at extending FeynHiggs to models beyond the MSSM.

Proposed method

• Combine state-of-the-art fixed-order (diagrammatic) and EFT calculations to predict MSSM Higgs masses for small and large SUSY scales.
• Implement optional DRbar renormalization of the stop sector and adapted two-loop Higgs sector renormalization.
• Incorporate non-degenerate threshold corrections at one- and two-loop level and interpolate EFT results for complex parameters.
• Include non-degenerate thresholds enabling independent gluino thresholds in NNLL resummation.
• Provide a 3x3 neutral Higgs propagator matrix with self-energies and logs for pole mass extraction.
• Describe improvements in the code structure to ease future extensions.

Experimental results

Research questions

• RQ1 How do fixed-order and EFT approaches combine to yield precise MSSM Higgs mass predictions across SUSY scales?
• RQ2 What specific renormalization scheme choices (OS/DRbar) improve fixed-order accuracy and their impact on resummation?
• RQ3 How do non-degenerate threshold corrections affect EFT matching and Higgs mass predictions?
• RQ4 Can complex parameters be reliably treated via interpolation within the EFT part of FeynHiggs?
• RQ5 What code-structure changes facilitate extensions beyond the MSSM?

Key findings

• FeynHiggs now supports an optional DRbar renormalization of the stop sector, improving flexibility and comparison to OS inputs.
• The Higgs sector renormalization at two loops is adapted to align input masses with physical masses, enhancing consistency.
• Non-degenerate threshold corrections at one- and two-loop levels are implemented in the EFT calculation, improving accuracy for hierarchies in SUSY masses.
• An interpolation for complex parameters in the EFT calculation enables handling of phases in practice.
• The code now features a more modular structure to ease extensions to models beyond the MSSM.