Two-loop corrections to radiative electroweak symmetry breaking in the MSSM

113

Taking the supersymmetric inverse seesaw mechanism as the explanation for neutrino oscillation data, we investigate charged lepton flavor violation in radiative and 3-body lepton decays as well as in neutrinoless µ − e conversion in muonic atoms. In contrast to former studies, we take into account all possible contributions: supersymmetric as well as non-supersymmetric. We take CMSSM-like boundary conditions for the soft supersymmetry breaking parameters. We find several regions where cancellations between various contributions exist, reducing the lepton flavor violating rates by an order of magnitude compared to the case where only the dominant contribution is taken into account. This is in particular important for the correct interpretation of existing data as well as for estimating the reach of near future experiments where the sensitivity will be improved by one to two orders of magnitude. Moreover, we demonstrate that ratios like BR(τ → 3µ)/BR(τ → µe + e − ) can be used to determine whether the supersymmetric contributions dominate over the W ± and H ± contributions or vice versa.

Section: Numerical Setupmentioning

confidence: 99%

Lepton flavor violation in low-scale seesaw models: SUSY and non-SUSY contributions

Abada

Krauss

Porod

et al. 2014

113

“…For our numerical analyses we use SPheno [40,41] created by SARAH [42][43][44][45]. This version performs a complete one-loop calculation of all SUSY and Higgs masses [46,47] and includes the dominant two-loop corrections for the scalar Higgs masses [48][49][50][51]. We have extended SPheno by incorporating routines to calculate the fine tuning as presented in [15].…”

Section: Susy Higgs and Dm Cutsmentioning

confidence: 99%

Non-universal gaugino masses and fine tuning implications for SUSY searches in the MSSM and the GNMSSM

Kaminska

Ross

Schmidt-Hoberg

2013

For the case of the MSSM and the most general form of the NMSSM (GN-MSSM) we determine the reduction in the fine tuning that follows from allowing gaugino masses to be non-degenerate at the unification scale, taking account of the LHC8 bounds on SUSY masses, the Higgs mass bound, gauge coupling unification and the requirement of an acceptable dark matter density. We show that low-fine tuned points fall in the region of gaugino mass ratios predicted by specific unified and string models. For the case of the MSSM the minimum fine tuning is still large, approximately 1:60 allowing for a 3 GeV uncertainty in the Higgs mass (1:500 for the central value), but for the GNMSSM it is below 1:20. We find that the spectrum of SUSY states corresponding to the low-fine tuned points in the GNMSSM is often compressed, weakening the LHC bounds on coloured states. The prospect for testing the remaining low-fine-tuned regions at LHC14 is discussed.

“…For this purpose we use the SPheno version [78,79] for the GNMSSM created by SARAH [80][81][82][83] which has been presented in [55]. This version performs a complete oneloop calculation of all SUSY and Higgs masses [84,85] and includes the dominant two-loop corrections for the scalar Higgs masses [86][87][88][89]. In addition, it calculates the decay widths and branching ratios of all SUSY and Higgs particles.…”

Section: A Benchmark Scenariomentioning

confidence: 99%

Enhanced diphoton rates at Fermi and the LHC

Schmidt-Hoberg

Staub²,

Winkler

2013

We show that within MSSM singlet extensions the experimental hints beyond the standard model from the Fermi LAT telescope as well as from the LHC can be explained simultaneously while being consistent with all experimental constraints. In particular we present an example point which features a ∼ 130 GeV lightest neutralino with an annihilation cross section into photons consistent with the indication from the Fermi satellite with simultaneously the right relic abundance, a continuum photon spectrum consistent with observation, direct detection cross section below the experimental limits, electroweak observables consistent with experiment and a 125 GeV light Higgs boson with a slightly enhanced h → γγ rate.