GM2Calc: Precise MSSM prediction for $(g - 2)$ of the muon
Peter Athron, Markus Bach, Helvecio G. Fargnoli, Christoph Gnendiger, Robert Greifenhagen, Jae-hyeon Park, Sebastian Paßehr, Dominik Stöckinger, Hyejung Stöckin… 展开作者
Peter Athron, Markus Bach, Helvecio G. Fargnoli, Christoph Gnendiger, Robert Greifenhagen, Jae-hyeon Park, Sebastian Paßehr, Dominik Stöckinger, Hyejung Stöckinger-Kim, Alexander Voigt
备注：
27 pages, 4 figures, 4 listings; version sent to EPJC
We present GM2Calc, a public C++ program for the calculation of MSSM contributions to the anomalous magnetic moment of the muon, $(g-2)_μ$. The code computes $(g-2)_μ$ precisely, by taking into account the latest two-loop corrections and by performing the calculation in a physical on-shell renormalization scheme. In particular the program includes a $\tanβ$ resummation so that it is valid for arbitrarily high values of $\tanβ$, as well as fermion/sfermion-loop corrections which lead to non-decoupling effects from heavy squarks. GM2Calc can be run with a standard SLHA input file, internally converting the input into on-shell parameters. Alternatively, input parameters may be specified directly in this on-shell scheme. In both cases the input file allows one to switch on/off individual contributions to study their relative impact. This paper also provides typical usage examples not only in conjunction with spectrum generators and plotting programs but also as C++ subroutines linked to other programs.
The precision observables M_W and g-2 of the muon are discussed in the framework of the MSSM. Recent progress in the evaluation of the theoretical predictions is described, and the MSSM predictions are compared with the SM predictions and the experimental values.
The current experimental values of anomalous magnetic moments of muon and electron deviate from the Standard Model predictions by few standard deviations, which might be a hint of new physics. The sizes and signs of these deviations are different and opposite between the electron and muon, which makes it difficult to explain both of these anomalies in a consistent model without introducing large flavour-violating effects. It is shown that they can be simultaneously explained in the Minimal Supersymmetric Standard Model (MSSM) by arranging the sizes of bino-slepton and chargino-sneutrino contri…
If the one term $(\hat ν_e \hat μ- \hat e \hat ν_μ) \hat τ^c$ is added to the MSSM (Minimal Supersymmetric Standard Model) superpotential, the recently observed muon g--2 (anomalous magnetic moment) excess can be explained very simply by a light $\tilde ν_e$. If the soft symmetry-breaking terms $\hat ν_α\hat h_2^0 - \hat l_α\hat h_2^+$ are also added, realistic neutrino masses (with bimaximal mixing) are generated as well.
We explore the possibility of distinguishing the SM-like MSSM Higgs boson from the SM Higgs boson via Higgs boson pair production at future muon collider. We study the behavior of the production cross section in SM and MSSM with Higgs boson mass for various choices of MSSM parameters tan βand m\sub A. We observe that at fixed CM energy, in the SM, the total cross section increases with the increase in Higgs boson mass whereas this trend is reversed for the MSSM case. The changes that occur for the MSSM case in comparison to the SM predictions are quantified in terms of the relative percentage …
The minimal supersymmetric extension of standard model (MSSM) is examined by analyzing its quantum effects on the precision electroweak measurements and the muon g-2. We examine carefully the effects of light charginos and neutralinos that are found to improve the fit to the electroweak data. We identify two distinct regions on the $(μ, M_2)$-plane that fit well to the electroweak data and give significant contribution to muon g-2.
We study phenomenological aspects of the MSSM with extra U(1) gauge symmetry. We find that the lightest Higgs boson mass can be increased up to 125 GeV, without introducing a large SUSY scale or large A-terms, in the frameworks of the CMSSM and gauge mediated SUSY breaking (GMSB) models. This scenario can simultaneously explain the discrepancy of the muon anomalous magnetic moment (muon g-2) at the 1 sigma level, in both of the frameworks, U(1)-extended CMSSM/GMSB models. In the CMSSM case, the dark matter abundance can also be explained.
We give a simultaneous analysis of $g_μ-2$ and lepton flavor violation within MSSM. Working on the interaction basis, we give direct relations between $δa_μ$ and Br$(τ\toμγ)$ induced by the supersymmetric particles. We find the SUSY parameter space to satisfy the $g_μ-2$ constraint can be considerably different from that given in case of no lepton flavor mixing in the soft SUSY breaking sector.
A muon collider with controllable energy resolution and transverse beam polarization provides a powerful probe of the Higgs sector in the minimal supersymmetric standard model with explicit CP violation, through s-channel production of Higgs bosons. The production rates and the CP-even and CP-odd transverse-polarization asymmetries are complementary in diagnosing CP violation in the Higgs sector.
The muon anomalous magnetic moment $a_μ$ is studied in the infinite $\tanβ$ limit of the MSSM. Since the muon mass arises completely from loop effects, large corrections to $a_μ$ are expected in comparison to the usual case with moderately high $\tanβ$. Due to the qualitatively different parameter dependence, the gap between the experimental value and the Standard Model prediction can be filled only in parameter volumes in which a mass hierarchy suppresses the chargino loop in favour of the neutralino contribution. Two such possibilities are found to have either large Higgsino mass or large mu…
We show that the best fits of the MSSM constrained by a simple SO(10) SUSY GUT are consistent with the present data on the muon anomalous magnetic moment. The best fits assume rather large values of tan$β\approx 50$, and in our analysis they are not {\em a priori} correlated in any way, directly or indirectly, with the experimental limit on $a_μ$. Regions in the SUSY parameter space, which are currently ruled out because of too large $a_μ^{SUSY}$, are already excluded in the global fit by excessive corrections to $m_b$, unacceptable $BR(b\to sγ)$, or direct experimental limits on sparticle mas…
We investigate the possibility that both dark matter and the long-standing discrepancy in the anomalous magnetic moment of the muon may be explained within the MSSM. In light of the stringent bounds from direct detection, we argue that the most promising viable scenarios have bino-like dark matter produced via either bino-wino or bino-slepton co-annihilation. We find that the combination of next-generation direct detection experiments and the LHC will be able to probe much of the interesting parameter space, however a future high-energy collider is needed to comprehensively explore this scenar…
We demonstrate that the recent measurement of the anomalous magnetic moment of the muon and dark matter can be simultaneously explained within the Minimal Supersymmetric Standard Model. Dark matter is a mostly-bino state, with the relic abundance obtained via co-annihilations with either the sleptons or wino. The most interesting regions of parameter space will be tested by the next generation of dark matter direct detection experiments.
We study the constraints of the CP violation in the muon $g-2$ preferred region of the minimal supersymmetric standard model assuming a universal slepton masses within first two generations. We present two particular scenarios where the $g-2$ anomaly is predicted within 2 $σ$ level mainly through the chargino loop or the bino loop. We found that for both cases the electron EDM experiment already highly constrained the CP phase of the parameters: either the Arg[$μM_1]$ or Arg[$μM_2]$ should be smaller than $\mathcal O$(2-3)$\times10^{-5}$. If the muon $g-2$ anomaly is explained by the MSSM, a p…
We establish a correspondence between those Feynman diagrams in the MSSM which give supersymmetric contributions to the muon anomalous magnetic moment and those which contribute to the flavor violating processes $μ--> eγ$ and $τ--> μγ$. Using current experimental limits on the branching ratios of these decay modes, combined with the assumption of a supersymmetric contribution to the muon anomalous magnetic moment, we establish bounds on the size of the lepton flavor violating soft masses in the MSSM largely independent of assumptions about other supersymmetric parameters. If the deviation meas…
We study the electric dipole moment (EDM) and the anomalous magnetic dipole moment (MDM) of the muon in the CP-violating Minimal Supersymmetric extension of the Standard Model (MSSM). We take into account the contributions from the chargino- and neutralino-mediated one-loop graphs and the dominant two-loop Higgs-mediated Barr-Zee diagrams. We improve earlier calculations by incorporating CP-violating Higgs-boson mixing effects and the resummed threshold corrections to the Yukawa couplings of the charged leptons as well as that of the bottom quark. The analytic correlation between the muon EDM …
We present recent results of two interesting classes of supersymmetric two-loop contributions to (g-2)_mu. Two-loop diagrams involving either a closed sfermion loop or a closed chargino/neutralino loop can amount to 5*10^{-10}, which is almost one standard deviation of the current experimental uncertainty. We discuss the dependence of these two classes on the unknown supersymmetric parameters and their impact on the supersymmetric prediction of (g-2)_mu.
We investigate the muon anomalous magnetic dipole moment (MDM), the muon electric dipole moment (EDM) and the lepton-flavour-violating decays of the $τ-$lepton, $τ\to μγ$ and $τ\to 3μ$, in the CP-violating Minimal Supersymmetric Standard Model (MSSM) with nonuniversal soft-supersymmetry breaking. We evaluate numerically the muon EDM and the branching ratios $B(τ\to μγ)$ and $B(τ\to 3μ)$, after taking into account the experimental constraints from the electron EDM and muon MDM. Upon imposition of the experimental limits on our theoretical predictions for the aforementioned branching ratios and …
The Fermi-Lab Collaboration has announced the results for the measurement of muon anomalous magnetic moment. Combining with the previous results by the BNL experiment, we have $4.2 σ$ deviation from the Standard Model (SM), which strongly implies the new physics around 1 TeV. To explain the muon anomalous magnetic moment naturally, we analyze the corresponding five Feynman diagrams in the Supersymetric SMs (SSMs), and show that the Electroweak Supersymmetry (EWSUSY) is definitely needed. We realize the EWSUSY in the Minimal SSM (MSSM) with Genernalized Mininal Supergravity (GmSUGRA). We find l…
We analyze two minimal supersymmetric constrained models with low-energy vector-like matter preserving gauge coupling unification. In one we add to the MSSM spectrum a pair of 5-plets of SU(5), in the other a pair of 10-plets. We show that the muon g-2 anomaly can be explained in these models while retaining perturbativity up to the unification scale, satisfying electroweak and flavor precision tests and current LHC data. We examine also some related phenomenological features of the models, including Higgs mass, fine-tuning, dark matter and several LHC signatures. We stress that, at least for …
Recent progress on the (g-2)_μprediction is presented. In the SM, the Higgs-boson mass dependent contributions have been evaluated exactly up to the two-loop level and consistently combined with leading three-loop effects. Thus, the currently most accurate value including a detailed error analysis for the SM electroweak contributions has been obtained. The SUSY two-loop corrections from fermion/sfermion-loop insertions have been computed; they are generally large and logarithmically enhanced for heavy squarks.
Recently, first results were presented for two-loop corrections to the muon (g-2) from fermion/sfermion loops in the MSSM. These corrections were shown to be generally large and even logarithmically enhanced for heavy sfermions. Here, full details of the calculation and analytical results are presented. Also, a very compact formula is provided which can be easily implemented and serves as a good approximation of the full result as a function of the fourteen most important input parameters. Finally, a thorough discussion of the numerical behaviour of the fermion/sfermion-loop corrections to (g-…
We update the electroweak study of the predictions of the Minimal Supersymmetric Standard Model (MSSM) including the recent results on the muon anomalous magnetic moment, the weak boson masses, and the final precision data on the Z boson parameters from LEP and SLC. We find that the region of the parameter space where the slepton masses are a few hundred GeV is favored from the muon g-2 for \tanβ\ltsim 10, whereas for \tanβ\simeq 50 heavier slepton mass up to \sim 1000 GeV can account for the reported 3.2 σdifference between its experimental value and the Standard Model (SM) prediction. As for…
The muon $g-2$ anomaly is a long-standing discrepancy from its standard model prediction. The recent improved measurement of the fine structure constant makes the electron $g-2$ anomaly very interesting for both sign and magnitude in comparison to the muon $g-2$ anomaly. In order to explain both muon and electron $g-2$ anomalies, we introduce flavor violation in the minimal supersymmetric standard model (MSSM) as a low energy theory. The lepton flavor violating process $τ\to eγ$ is one the major constraints to explain both $g-2$ anomalies simultaneously emerging from flavor violating terms. We…
We give a thorough analysis of the correlation between the muon anomalous magnetic moment and the radiative lepton flavor violating (LFV) processes within the minimal supersymmetric standard model. We find that in the case when the slepton mass eigenstates are nearly degenerate, $δa_μ$, coming from SUSY contributions, hardly depends on the lepton flavor mixing and, thus, there is no direct relation between $δa_μ$ and the LFV processes. On the contrary, if the first two generations' sleptons are much heavier than the 3rd one, i.e., in the effective SUSY scenario, the two quantities are closely …
The muon anomalous magnetic dipole moment (MDM) is calculated in the framework of the minimal supersymmetric standard model (MSSM). In this paper, we discuss how the muon MDM depends on the parameters in MSSM in detail. We show that the contribution of the superparticle-loop becomes significant especially when $\tanβ$ is large. Numerically, it becomes $O(10^{-8}-10^{-9})$ in a wide parameter space, which is within the reach of the new Brookhaven E821 experiment.
We perform a systematic study of the production of a third-generation fermion-pair, $μ^+μ^-\to f\bar{f}$ for $f=τ^-,b$, and t in the minimal supersymmetric standard model (MSSM) with explicit CP violation, which is induced radiatively by soft trilinear interactions related to squarks of the third generation. We classify all the observables for probing the CP property of the Higgs bosons constructed by the initial muon beam polarization along with the unpolarized final fermions and with the final-fermion polarization configuration of equal helicity, respectively. The observables allow for compl…
We analyse the low energy predictions of the minimal supersymmetric standard model (MSSM) arising from a GUT scale Pati-Salam gauge group further constrained by an $A_4 \times Z_5$ family symmetry, resulting in four soft scalar masses at the GUT scale: one left-handed soft mass $m_0$ and three right-handed soft masses $m_1,m_2,m_3$, one for each generation. We demonstrate that this model, which was initially developed to describe the neutrino sector, can explain collider and non-collider measurements such as the dark matter relic density, the Higgs boson mass and, in particular, the anomalous …
The measurement of the anomalous magnetic moment of the muon exhibits a long standing discrepancy compared to the Standard model prediction. In this paper, we concentrate on this issue in the framework of $R$-parity violating Minimal supersymmetric standard model. Such a scenario provides substantial contribution to the anomalous magnetic moment of the muon while satisfying constraints from low energy experimental observables as well as neutrino mass. In addition, we point out that the implication of such operators satisfying muon $g-2$ are immense from the perspective of the LHC experiment, l…
In general, we can propose the hybrid supersymmetry breakings and hybrid mediations in the Supersymmetric Standard Models (SSMs). In this paper, we study the hybrid mediation for supersymmetry (SUSY) breaking. In particular, we study how to keep the good properties of gravity mediation, gauge mediation, and anomaly mediation, while solve their problems simultaneously. As an example, we consider the anomaly-gravity mediation, where all the supersymmetric particles (sparticles) obtain the SUSY breaking soft terms from the traditional gravity mediation while gauge mediation gives dominant contrib…
The discovery of the Higgs boson at the Large Hadron Collider (LHC) has a great impact on the minimal supersymmetric extension of the Standard Model (MSSM). In the context of the constrained MSSM (CMSSM) and its extension with non-universal masses for the MSSM Higgs doublets (NUHM2), sparticles with masses $ > 1$ TeV are necessary to reproduce the observed Higgs boson mass of 125-126 GeV. On the other hand, there appears to be a significant amount of discrepancy between the measured muon $g-2$ and the Standard Model prediction. A successful explanation of this discrepancy in the MSSM requires …
We discuss a generalization of the minimal supersymmetric extension of the Standard Model in the form of three additional singlet superfields, which would explain the essential features of the CDF multi-muon events presented recently: a large production cross section of ~ 100 pb originates from the production of a CP-odd scalar A with a mass in the 70 - 80 GeV range and a large value of tan(beta) ~ 40. The CP-odd scalar A decays dominantly into CP-odd and CP-even scalars a_1 and h_1, which generate decay cascades h_1 -> 2 h_2 -> 4 a_2 -> 8 tau-leptons, and a_1 -> h_1 a_2 with h_1 decaying as a…
In view of the recent measurement of the muon g-2 and finalization of the LEP electroweak data, we re-examine all the new particle contributions to those observables in the MSSM. The SM fits the latest electroweak data excellently with the observed top-quark mass and the Higgs-boson mass of around 100 GeV, and so does the MSSM in the decoupling limit. The MSSM gives a slightly better fit to the data than the SM (Δχ^2_{min} \sim -2) when relatively light left-handed sleptons of mass \sim 200 GeV and a light chargino of mixed higgsino-wino character (μ/M_2 \sim 1) with mass \sim 100 GeV co-exist…
Effects of CP violation on the supersymmetric electro-weak correction to the anomalous magnetic moment of the muon are investigated with the most general allowed set of CP violating phases in MSSM. The analysis includes contributions from the chargino and the neutralino exchanges to the muon anomaly. The supersymmetric contributions depend only on specific combinations of CP phases. The independent set of such phases is classified. We analyse the effects of the phases under the EDM constraints and show that large CP violating phases can drastically affect the magnitude of the supersymmetric el…
As discussed recently by Hooper and Tait, the singlino-like dark matter in the Minimal Supersymmetric Standard Model (MSSM) extended by a singlet Higgs superfield can give a perfect explanation for both the relic density and the Pamela result through the Sommerfeld-enhanced annihilation into singlet Higgs bosons ($a$ or $h$ followed by $h->a a$) with $a$ being light enough to decay dominantly to muons or electrons. In this work we analyze the parameter space required by such a dark matter explanation and also consider the constraints from the LEP experiments. We find that although the light si…
The recent experimental results including $R_{K^{(\ast)}}$, $R_{D^{(\ast)}}$, $(g-2)_μ$ and $W$ mass show deviations from the standard model (SM) predictions, implying the clues of new physics (NP). In this work, we investigate the explanations of these anomalies in the $R$-parity violating minimal supersymmetric standard model (RPV-MSSM) extended with the inverse seesaw mechanism. The non-unitarity extent $η_{ee}$ and the loop corrections from the interaction $λ'\hat L \hat Q \hat D$ are utilized to raise the prediction of $W$ mass through muon decays. We also find that the interaction $λ'\ha…
The electroweak (EW) sector of the Minimal Supersymmetric extension of the Standard Model (MSSM), assuming the lightest neutralino as Dark Matter (DM) candidate, can account for a variety of experimental results. In particular it can account for the discrepancy between the experimental result for the anomalous magnetic moment of the muon, $(g-2)_μ$, and its Standard Model (SM) prediction. The new "MUON G-2" result, combined with the older BNL result on $(g-2)_μ$, yields a deviation from the SM prediction of $Δa_μ = (25.1 \pm 5.9) \times 10^{-10}$, corresponding to $4.2~σ$. Using this updated b…
Motivated by the tension between the Higgs mass and muon g-2 in minimal supersymmetric standard model (MSSM), we analyze the muon g-2 in supersymmertic B-L extension of the standard model (BLSSM) with inverse seesaw mechanism. In this model, the Higgs mass receives extra important radiative corrections proportional to large neutrino Yukawa coupling. We point out that muon g-2 also gets significant contribution, due to the constructive interferences of light neutralino effects. The light neutralinos are typically the MSSM Bino like and the supersymmetric partner of U(1)_B-L gauge boson (B'-ino)…
The recent results of the LHC search for electroweak production of supersymmetric (SUSY) particles at $\sqrt{s}=13$ TeV have shown improved lower limits for their masses. In addition, the projected experiment E989 will be able to measure the muon anomalous magnetic moment precisely so that the experimental uncertainty can be reduced by a factor of four. It was pointed out that if the center value of the muon $g-2$ remains unchanged the deviation between the standard model (SM) prediction and the experimental value will be as large as 7.0$σ$. Such a large deviation will be solid evidence for ne…
In the MSSM, the tension between the observed Higgs boson mass and the experimental result of the muon $g-2$ measurement requires a large mass splitting between stops and smuons/charginos/neutralinos. We consider a 5-dimensional (5D) framework of the MSSM with the Randall-Sundrum warped background metric, and show that such a mass hierarchy is naturally achieved in terms of geometry. In our setup, the supersymmetry is broken at the ultraviolet (UV) brane, while all the MSSM multiplets reside in the 5D bulk. An appropriate choice of the bulk mass parameters for the MSSM matter multiplets can na…
We report on a two-loop supersymmetric contribution to the magnetic moment (g-2)_mu of the muon which is enhanced by two powers of tan(beta). This contribution arises from a shift in the relation between the muon mass and Yukawa coupling and can increase the supersymmetric contribution to (g-2)_mu sizably. As a result, if the currently observed 3 sigma deviation between the experimental and SM theory value of (g-2)_mu is analyzed within the Minimal Supersymmetric Standard Model (MSSM), the derived constraints on the parameter space are modified significantly: If (g-2)_mu is used to determine t…
We study the muon anomalous magnetic moment a_μ= (g_μ- 2)/2 in a supersymmetric U(1)' model. The neutralino sector has extra components from the superpartners of the U(1)' gauge boson and the extra Higgs singlets that break the U(1)' symmetry. The theoretical maximum bound on the lightest neutralino mass is much smaller than that of the Minimal Supersymmetric Standard Model (MSSM) because of the mixing pattern of the extra components. In a U(1)' model where the U(1)' symmetry is broken by a secluded sector (the S-model), tanβis required to be < 3 to have realistic electroweak symmetry breaking…
We employ two different statistical tests to examine whether, in the framework of the Constrained MSSM, the experimentally determined values of BR(b->s gamma) and the anomalous magnetic moment of the muon, (g-2), are consistent with each other. Our tests are designed to compare the theoretical predictions of the CMSSM in data space with the actual measurements, once all of the CMSSM free parameters have been integrated out and constrained using all other available data. We investigate the value of (g-2) as obtained by using e+e- data alone (which shows a ~3sigma discrepancy with the SM predict…
The recent Fermilab muon $g-2$ result and the same for electron due to fine-structure constant measurement through ${}^{133}{\rm Cs}$ matter-wave interferometry are probed in relation to MSSM with non-holomorphic (NH) trilinear soft SUSY breaking terms, referred as NHSSM. Supersymmetric contributions to charged lepton $(g-2)_l$ can be enhanced via the new trilinear terms involving a wrong Higgs coupling with left and right-handed scalars. Unlike many MSSM based analyses, the model does not require a light electroweakino, or light sleptons, or unequal left and right slepton masses, or a very la…
This contribution describes precision width measurements that could be done at a muon collider for very narrow resonances as the Higgs or a possible pseudogoldstone boson, or for almost degenerate resonances as the A0 and H0 in the MSSM for large values of tanβ.
Different approaches are used for the calculation of the SM-like Higgs boson mass in the MSSM: the fixed-order diagrammatic approach is accurate for low SUSY scales; the EFT approach,for high SUSY scales. Hybrid approaches, combining fixed-order and EFT calculations, allow to obtain a precise prediction also for intermediary SUSY scales. Here, we briefly discuss the hybrid approach implemented into the code FeynHiggs. In addition, we show how the refined Higgs mass prediction was used to define new MSSM Higgs benchmark scenarios.
We explore the ability of current and future dark matter and collider experiments in probing anomalous magnetic moment of the muon, $(g-2)_μ$, within the Minimal Supersymmetric Standard Model (MSSM). We find that the latest PandaX-II/LUX-2016 data gives a strong constraint on parameter space that accommodates the $(g-2)_μ$ within $2σ$ range, which will be further excluded by the upcoming XENON-1T (2017) experiment. We also find that a 100 TeV $pp$ collider can cover most of our surviving samples that satisfy DM relic density within $3σ$ range through $Z$ or $h$ resonant effect by searching for…
The theoretical predictions in the standard model (SM) and measurements on the anomalous magnetic dipole moments (MDM) of muon and electron have great precision, hence the MDMs of muon and electron have close relation with the new physics (NP) beyond the SM. Recently, a negative $\sim2.4σ$ discrepancy between the measured electron MDM and the SM prediction results from a recent improved determination of the fine structure constant. Combined with the long-lasting muon MDM discrepancy which is about $\sim3.7σ$, it is difficult to explain both the magnitude and opposite signs of the deviations in…
The Higgs boson of 125 GeV requires large stop masses, leading to the large $μ$-parameter in most cases of gauge mediation. On the other hand, the explanation for the muon $g-2$ anomaly needs small slepton and neutralino/chargino masses. Such disparity in masses may be obtained from a mass splitting of colored and non-colored messenger fields. However, even if the required small slepton and neutralino/chargino masses are realized, all parameter regions consistent with the muon g-2 are excluded by the recent updated ATLAS result on the wino search in the case that the messenger fields are in ${…
We present the currently most accurate evaluation of the W boson mass, M_W, in the Minimal Supersymmetric Standard Model (MSSM). The full complex phase dependence at the one-loop level, all available MSSM two-loop corrections as well as the full Standard Model result have been included. We analyse the impact of the different sectors of the MSSM at the one-loop level with a particular emphasis on the effect of the complex phases. We discuss the prediction for M_W based on all known higher-order contributions in representative MSSM scenarios. Furthermore we obtain an estimate of the remaining th…
The muon anomalous magnetic moment $a_μ$ is investigated in the MSSM for $\tanβ\to\infty$. This is an attractive example of radiative muon mass generation with completely different qualitative parameter dependence compared to the MSSM with the usual, finite $\tanβ$. The observed, positive difference between the experimental and Standard Model value can only be explained if there are mass splittings, such that bino contributions dominate over wino ones. The two most promising cases are characterized either by large Higgsino mass $μ$ or by large left-handed smuon mass $m_L$. The required mass sp…
In the framework of the MSSM extension with local gauged baryon and lepton numbers (BLMSSM), we calculate the muon anomalous magnetic dipole moment (MDM) and lepton $(e, μ, τ)$ electric dipole moment (EDM), and discuss how the muon MDM and lepton EDM depend on the parameters within the mass insertion approximation. Among many parameters, $\tanβ$,~$g_L$,~$m_L$ and $μ_H$ are more sensitive parameters for $a^{BL}_μ$. Considering the experimental limitations, our best numerical result of $a^{BL}_μ$ is around $2.5 \times 10^{-9}$, which can well compensate the departure between the experiment data …
In this letter, we show that the wino-Higgsino dark matter (DM) is detectable in near future DM direct detection experiments for almost all consistent parameter space in the spontaneously broken supergravity (SUGRA) if the muon g-2 anomaly is explained by the wino-Higgsino loop diagrams. We also point out that the present and future LHC experiments can exclude or confirm this SUGRA explanation of the observed muon g-2 anomaly.
We revisit the current LHC constraints on the electroweak-ino sector parameters in the minimal supersymmetric standard model (MSSM) that are relevant to explaining the $(g-2)_μ$ anomaly via the dominant chargino and muon sneutrino loop. Since the LHC bounds on electroweak-inos become weaker if they decay via an intermediate stau or a tau sneutrino instead of the first two generation sleptons, we perform a detailed analysis of the scenario with a bino as the lightest supersymmetric particle (LSP) and a light stau as the next-to-lightest one (NLSP). Even in this scenario, the chargino sector par…
The new CDF II measurement of $W$-boson mass shows a 7$σ$ deviation from the Standard Model (SM) prediction, while the recent FNAL measurement of the muon $g-2$ shows a 4.2$σ$ deviation (combined with the BNL result) from the SM. Both of them strongly indicate new physics beyond the SM. In this work we study the implication of both measurements on low energy supersymmetry. With an extensive exploration of the parameter space of the minimal supersymmetric standard model (MSSM), we find that in the parameter space allowed by current experimental constraints from colliders and dark matter detecti…
The long-standing discrepancy between the experimental determination by the Muon $g-2$ Collaboration at Brookhaven and the Standard Model predictions for the anomalous magnetic moment of the muon cannot be explained within simple unified framework like the Constrained Minimal Supersymmetric Standard Model, but it can within its extension with vector-like fermions. In this paper we consider a model with an additional vector-like $5+\bar{5}$ pair of $SU(5)$. Within this model we first identify its parameter space that is consistent with the current discrepancy and show that this implies the ligh…
The main production mechanism for supersymmetric Higgs particles at hadron colliders crucially depends on the size of their Yukawa couplings to bottom quarks. For sufficiently large tan(beta) the total cross section for some of the neutral Higgs bosons in the MSSM is dominated by bottom-quark fusion. After an introduction to bottom-associated Higgs production, we discuss the complete O(alpha) electroweak and O(alpha_s) strong corrections for the bb-fusion channel in the MSSM. Choosing proper renormalization and input-parameter schemes, an improved Born approximation, constructed from previousl…
We study the interplay between a soft muon Yukawa coupling generated radiatively with the trilinear A-terms of the minimal supersymmetric standard model (MSSM) and the anomalous magnetic moment of the muon. In the absence of a tree-level muon Yukawa coupling the lightest smuon mass is predicted to be in the range between 750 GeV and 2700 GeV at 2 sigma, if the bino mass M_1 is below 1 TeV. Therefore, a detection of a smuon (in conjunction with a sub-TeV bino) at the LHC would directly imply a non-zero muon Yukawa coupling in the MSSM superpotential. Inclusion of slepton flavor mixing could in …
With the latest Planck results the dark matter relic density is determined to an unprecedented precision. In order to reduce current theoretical uncertainties in the dark matter relic density prediction, we have calculated next-to-leading order SUSY-QCD corrections to neutralino (co)annihilation processes including Coulomb enhancement effects. We demonstrate that these corrections can have significant impact on the cosmologically favoured MSSM parameter space and are thus of general interest for parameter studies and global fits.
We review the comparison of the results for the neutral CP-even Higgs-boson masses recently obtained within the Feynman-diagrammatic approach with the previous results based on the renormalization group approach. We show that the results differ by new genuine two-loop contributions present in the Feynman-diagrammatic calculation. The numerical effect of these terms on the result for m_h is briefly discussed.
