Predicting the sparticle spectrum from GUTs via SUSY threshold corrections with SusyTC

Abstract

Grand Unified Theories (GUTs) can feature predictions for the ratios of quark and lepton Yukawa couplings at high energy, which can be tested with the increasingly precise results for the fermion masses, given at low energies. To perform such tests, the renormalization group (RG) running has to be performed with sufficient accuracy. In supersymmetric (SUSY) theories, the one-loop threshold corrections (TC) are of particular importance and, since they affect the quark-lepton mass relations, link a given GUT flavour model to the sparticle spectrum. To accurately study such predictions, we extend and generalize various formulas in the literature which are needed for a precision analysis of SUSY flavour GUT models. We introduce the new software tool SusyTC, a major extension to the Mathematica package REAP [1], where these formulas are implemented. SusyTC extends the functionality of REAP by a full inclusion of the (complex) MSSM SUSY sector and a careful calculation of the one-loop SUSY threshold corrections for the full down-type quark, up-type quark and charged lepton Yukawa coupling matrices in the electroweak-unbroken phase. Among other useful features, SusyTC calculates the one-loop corrected pole mass of the charged (or the CP-odd) Higgs boson as well as provides output in SLHA conventions, i.e. the necessary input for external software, e.g. for performing a two-loop Higgs mass calculation. We apply SusyTC to study the predictions for the parameters of the CMSSM (mSUGRA) SUSY scenario from the set of GUT scale Yukawa relations

Predictions from a flavour GUT model combined with a SUSY breaking sector

“…[38]). 3 • Connected to the above, in the dark matter sector we predict the correlation between the WIMP mass and the WIMP-nucleon cross section. Since the WIMP is the neutralino, figure 2 shows the 1σ and 2σ HPD regions of the MCMC analysis as well as the sensitivities of the XENON1T and the XENONnT experiments [37].…”

“…E.g., the model can then also predict ranges for the sparticle masses (cf. [3,4]), for the DM relic density, and for the various flavour violating processes and precision observables which can be used as indirect searches for new physics.…”

“…We followed the notation used in SusyTC [3], which in particular is the RL convention for the definition of the Yukawa matrices. The θ 2 , θ 102 , ξ 1 , ξ 2 and ξ u are additional flavon fields that are singlets under A 4 .…”

“…In addition, the squared soft masses of the right-handed neutrinos have the form (5) is a simple Lie group, and assuming a simple gauge kinetic function of the form f ab = f (φ)δ ab , the three soft masses of the MSSM's gauginos are all given by the same mass parameter m λ at the GUT scale. For the definition of the soft terms we followed again the notation used in SusyTC [3].…”

“…The numerical analysis is performed in the following way: using the one-loop MSSM and soft term RGEs, we run the parameters from M GUT = 2 · 10 16 GeV down to Λ SUSY with the Mathematica package SusyTC [3], which is an extension of the Mathematica package REAP [18]. The heavy, right-handed neutrinos are integrated out at their corresponding mass scales.…”