Next-to-minimal SOFTSUSY

Abstract:We provide the two-loop corrections to the Higgs boson masses of the CPviolating NMSSM in the Feynman diagrammatic approach with vanishing external momentum at O(α t α s ). The adopted renormalization scheme is a mixture between DR and on-shell conditions. Additionally, the renormalization of the top/stop sector is provided both for the DR and the on-shell scheme. The calculation is performed in the gaugeless limit. We find that the two-loop corrections compared to the one-loop corrections are of the order of 5-10%, depending on the top/stop renormalization scheme. The theoretical error on the Higgs boson masses is reduced due to the inclusion of these higher order corrections.

Section: Jhep05(2015)128mentioning

confidence: 99%

Two-loop contributions of the order O α t α s $$ \mathcal{O}\left({\alpha}_t{\alpha}_s\right) $$ to the masses of the Higgs bosons in the CP-violating NMSSM

Mühlleitner

Nhung

Rzehak

et al. 2015

“…This allows us to calculate the mass spectrum of the model at the full one-loop level. With the recent framework FlexibleSUSY [47] v1.0.2, a second spectrum generator was generated which has similarities with Softsusy [48,49] and which was used for comparison. The correctness of all calculations was checked at great length, and especially details for the calculation of the Higgs and W boson mass will be presented in the following sections 3 and 4.…”

Section: Calculation Setup and Benchmark Pointsmentioning

confidence: 99%

Higgs boson mass and electroweak observables in the MRSSM

Diessner

Kalinowski

Kotlarski

et al. 2014

159

R-symmetry is a fundamental symmetry which can solve the SUSY flavor problem and relax the search limits on SUSY masses. Here we provide a complete next-toleading order computation and discussion of the lightest Higgs boson mass, the W boson mass and muon decay in the minimal R-symmetric SUSY model (MRSSM). This model contains non-MSSM particles including a Higgs triplet, Dirac gauginos and higgsinos, and leads to significant new tree-level and one-loop contributions to these observables. We show that the model can accommodate the measured values of the observables for interesting regions of parameter space with stop masses of order 1 TeV in spite of the absence of stop mixing. We characterize these regions and provide typical benchmark points, which are also checked against further experimental constraints. A detailed exposition of the model, its mass matrices and its Feynman rules relevant for computations in this paper is also provided.

“…[15]. For pMSSM models, the sparticle mass spectra were calculated with Softsusy 3.7.3 [44,45] MG5 aMC@NLO interfaced to PYTHIA8 for PS and hadronization was used to generate the tt+V (where V is a W or Z boson) and tt+γ samples at NLO with the NNPDF3.0NLO PDF set. The underlying-event tune used is A14 with the NNPDF2.3LO PDF set.…”

mentioning

confidence: 99%

Search for a scalar partner of the top quark in the jets plus missing transverse momentum final state at s = 13 $$ \sqrt{s}=13 $$ TeV with the ATLAS detector

Aaboud¹,

Aad²,

Abbott³

et al. 2017

106

A search for pair production of a scalar partner of the top quark in events with four or more jets plus missing transverse momentum is presented. An analysis of 36.1 fb −1 of √ s = 13 TeV proton-proton collisions collected using the ATLAS detector at the LHC yields no significant excess over the expected Standard Model background. To interpret the results a simplified supersymmetric model is used where the top squark is assumed to decay viat 1 → t ( * )χ0 1 andt 1 → bχ ± 1 → bW ( * )χ0 1 , whereχ 0 1 (χ ± 1 ) denotes the lightest neutralino (chargino). Exclusion limits are placed in terms of the top-squark and neutralino masses. Assuming a branching ratio of 100% to tχ 0 1 , top-squark masses in the range 450-1000 GeV are excluded forχ 0 1 masses below 160 GeV. In the case where mt The ATLAS collaboration 39 IntroductionSupersymmetry (SUSY) [1][2][3][4][5][6] is an extension of the Standard Model (SM) that can resolve, for example, the gauge hierarchy problem [7][8][9][10] by introducing supersymmetric partners of the known bosons and fermions. The SUSY partner to the top quark, the top squark (t), plays an important role in cancelling potentially large top-quark loop corrections in the Higgs boson mass. The superpartners of the left-and right-handed top quarks,t L and t R , mix to form the two mass eigenstatest 1 andt 2 , wheret 1 is the lighter one. Throughout this paper it is assumed that the analysis is only sensitive tot 1 . In R-parity-conserving SUSY models [11], the supersymmetric partners are produced in pairs. Top squarks are produced by strong interactions through quark-antiquark (qq) annihilation or gluon-gluon fusion, and the cross section of direct top-squark pair production is largely decoupled from the specific choice of SUSY model parameters [12][13][14][15]. The decay of the top squark depends on the mixing of the superpartners of left-and righthanded top quarks, the masses of the top superpartner, and the mixing parameters of the fermionic partners of the electroweak and Higgs bosons. The mass eigenstates of the partners of electroweak gauge and Higgs bosons (binos, winos, higgsinos) are collectively known as charginos,χ JHEP12(2017)085to be the lightest supersymmetric particle (LSP) which is stable and a dark-matter candidate [16,17]. For the models considered, eitherχ 0 2 orχ ± 1 is assumed to be the next lightest supersymmetric particle (NLSP). Three different decay scenarios are considered in this search: (a) both top squarks decay viat 1 → t ( * )χ 0 1 , (b) at least one of the top squarks decays viat 1 → bχ [18][19][20] where only one or two decay steps are allowed. In the case with two allowed decays, referred to later in this paper as a natural SUSY-inspired mixed grid, the mass splitting between theχ , is assumed to be 1 GeV. A grid of signal samples is generated across the plane of the top-squark andχ 0 1 masses with a grid spacing of 50 GeV across most of the plane, assuming maximal mixing between the partners of the left-and right-handed top quarks. In both the one-and ...