[Paper Review] Short review about the MSSM with three right-handed neutrinos (MSSM3RHN)

M. C. Rodriguez|arXiv (Cornell University)|Mar 10, 2020

Particle physics theoretical and experimental studies67 references6 citations

TL;DR

This paper presents a comprehensive review of the Minimal Supersymmetric Standard Model with three right-handed neutrinos (MSSM3RHN), extending the MSSM to include heavy Majorana neutrinos via superfields. It constructs the Lagrangian in superspace formalism, derives neutrino and sneutrino masses through Yukawa couplings and soft SUSY-breaking terms, and connects the model to broader supersymmetric frameworks like SUSYB-L, SUSYLR, and two SUSYGUTs, all featuring three right-handed neutrinos for neutrino mass generation and leptogenesis.

ABSTRACT

We give a review about the Minimal Supersymmetric Standard Model with three right-handed neutrinos (MSSM3RHN). We, first introduce the minimal set of fields to built this model in their superfields formalism. After it, we build the lagrangian of the model in the superspace formalism and also introduce the soft terms to break SUSY. We show how to get masses to the neutrinos and sneutrinos in this model.

Motivation & Objective

• To extend the Minimal Supersymmetric Standard Model (MSSM) by introducing three right-handed neutrino superfields to address neutrino masses and mixing.
• To construct the complete Lagrangian of the MSSM3RHN in superspace formalism, including superpotential and soft-breaking terms.
• To demonstrate how Majorana masses for neutrinos and sneutrinos arise via Yukawa couplings and the seesaw mechanism in a supersymmetric context.
• To connect the MSSM3RHN to broader supersymmetric models such as SUSYB-L, SUSYLR, and two SUSYGUT scenarios, all featuring three right-handed neutrinos.
• To provide a foundation for exploring leptogenesis, dark matter, and flavor physics in a supersymmetric framework with heavy right-handed neutrinos.

Proposed method

• The model is formulated using superfields, with three right-handed neutrino chiral supermultiplets added to the MSSM spectrum.
• The superpotential includes Yukawa couplings for charged leptons and Majorana neutrinos, enabling the seesaw mechanism for light neutrino masses.
• The Lagrangian is constructed in superspace, incorporating F-terms, D-terms, and kinetic terms for all fields, including gaugino and sfermion interactions.
• Soft SUSY-breaking terms are introduced via mass terms for scalar partners and gaugino masses, preserving gauge invariance and R-parity.
• The neutrino mass matrix is derived from the seesaw mechanism, with light neutrino masses suppressed by the large right-handed neutrino masses.
• The model is embedded in larger frameworks like SUSYB-L, SUSYLR, and two SUSYGUT models, all of which naturally accommodate three right-handed neutrinos.

Experimental results

Research questions

• RQ1 How can the MSSM be consistently extended to include three right-handed neutrinos while preserving supersymmetry and gauge invariance?
• RQ2 What is the structure of the superpotential and soft-breaking Lagrangian in the MSSM3RHN, and how do they generate neutrino masses?
• RQ3 How do the seesaw mechanism and Yukawa couplings in the MSSM3RHN lead to light Majorana neutrino masses and heavy right-handed neutrino states?
• RQ4 What are the implications of the MSSM3RHN for leptogenesis and baryogenesis in a supersymmetric context?
• RQ5 How does the MSSM3RHN relate to other supersymmetric grand unified theories (SUSYGUTs) and left-right symmetric models like SUSYLR and SUSYB-L?

Key findings

• The MSSM3RHN model successfully generates light Majorana neutrino masses via the seesaw mechanism, with the light neutrino mass matrix proportional to $ f^ u_{ij} rac{v^2}{M_R} $, where $ v $ is the Higgs VEV and $ M_R $ is the right-handed neutrino mass scale.
• The model includes a complete Lagrangian in superspace formalism, with F-terms, D-terms, and kinetic terms for all superfields, including the right-handed neutrino supermultiplets.
• Soft SUSY-breaking terms are consistently introduced, preserving R-parity and allowing for phenomenologically viable sfermion and gaugino masses.
• The model naturally embeds into larger frameworks such as SUSYB-L, SUSYLR, and two SUSYGUT models, all of which feature three right-handed neutrinos and can explain neutrino masses and leptogenesis.
• The seesaw mechanism in MSSM3RHN provides a viable mechanism for generating small neutrino masses and allows for the possibility of leptogenesis via decay of heavy right-handed neutrinos.
• The model offers a consistent framework for studying neutrino oscillations, dark matter (via sneutrino LSP), and flavor-changing processes in a supersymmetric extension of the Standard Model.