The Higgs mass and the scale of SUSY breaking in the NMSSM

TL;DR

This paper explores how the NMSSM allows for higher SUSY-breaking scales than the MSSM by analyzing the Higgs mass and the effects of the singlet on the quartic coupling at high energies.

Contribution

It demonstrates that the NMSSM's additional singlet contribution permits SUSY-breaking scales up to the GUT scale, unlike the MSSM which limits it near 10^{10} GeV.

Findings

In the NMSSM, the Higgs mass constrains SUSY-breaking scale up to the GUT scale.

The singlet contribution allows for negative quartic coupling at high scales.

Universal soft terms favor SUSY-breaking scales close to the GUT scale.

Abstract

In this letter we study the Higgs mass in the NMSSM with supersymmetry breaking at high scales $M_{SS}$. With the Standard Model as the effective low energy theory, the computation of the Higgs mass relies on the matching condition of the quartic coupling $\lambda$ at $M_{SS}$. In the MSSM, the latter is fixed to a semi-positive value and, thus, sets an upper bound on the SUSY-breaking scale near $M_{SS}\simeq 10^{10}\text{GeV}$. In the NMSSM, $\lambda(M_{SS})$ receives an additional contribution induced by the singlet which allows for negative values of $\lambda(M_{SS})$. In turn, for the measured value of the Higgs mass we find that $M_{SS}$ can take any value up to the GUT scale. Furthermore, the choice of universal soft terms favors SUSY-breaking scales close to the GUT scale.