$B_0\bar B_0$-Mixing Involving Supersymmetry

1997 ◽  
Vol 12 (06) ◽  
pp. 419-426 ◽  
Author(s):  
J. Urban ◽  
F. Krauss ◽  
Ch. Hofmann ◽  
G. Soff
Keyword(s):  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Minimal Supersymmetric Standard Model ◽  
Higgs Mass ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Feynman Diagrams ◽  
Lower Edge ◽  
Expectation Value ◽  
The Standard Model

We calculate all relevant Feynman-diagrams in lowest order for [Formula: see text]-mixing. We add to the Standard Model (SM) two scalar Higgs-doublets and take into account the Minimal Supersymmetric Standard Model (MSSM). Within the Standard Model which has been extended by two Higgs-doublets we find the following relation between the Higgs-mass and its vacuum expectation value (vev): mH=5000/7(au-0.43). Inclusion of the MSSM pushes the value of Vtd to the lower edge of the experimentally allowed range.

scholarly journals Weak scale from Planck scale: Mass scale generation in a classically conformal two-scalar system

2020 ◽  
Vol 2020 (3) ◽  
Author(s):  
Junichi Haruna ◽  
Hikaru Kawai
Keyword(s):  
Scalar Field ◽  
Standard Model ◽  
Planck Scale ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
The Other ◽  
Expectation Value ◽  
Weak Scale ◽  
The Standard Model ◽  
The One

Abstract In the standard model, the weak scale is the only parameter with mass dimensions. This means that the standard model itself cannot explain the origin of the weak scale. On the other hand, from the results of recent accelerator experiments, except for some small corrections, the standard model has increased the possibility of being an effective theory up to the Planck scale. From these facts, it is naturally inferred that the weak scale is determined by some dynamics from the Planck scale. In order to answer this question, we rely on the multiple point criticality principle as a clue and consider the classically conformal $\mathbb{Z}_2\times \mathbb{Z}_2$ invariant two-scalar model as a minimal model in which the weak scale is generated dynamically from the Planck scale. This model contains only two real scalar fields and does not contain any fermions or gauge fields. In this model, due to a Coleman–Weinberg-like mechanism, the one-scalar field spontaneously breaks the $ \mathbb{Z}_2$ symmetry with a vacuum expectation value connected with the cutoff momentum. We investigate this using the one-loop effective potential, renormalization group and large-$N$ limit. We also investigate whether it is possible to reproduce the mass term and vacuum expectation value of the Higgs field by coupling this model with the standard model in the Higgs portal framework. In this case, the one-scalar field that does not break $\mathbb{Z}_2$ can be a candidate for dark matter and have a mass of about several TeV in appropriate parameters. On the other hand, the other scalar field breaks $\mathbb{Z}_2$ and has a mass of several tens of GeV. These results will be verifiable in near-future experiments.

scholarly journals MUON ANOMALY AND A LOWER BOUND ON HIGGS MASS DUE TO A LIGHT STABILIZED RADION IN THE RANDALL–SUNDRUM MODEL

2006 ◽  
Vol 21 (26) ◽  
pp. 5205-5220 ◽  
Author(s):  
PRASANTA KUMAR DAS
Keyword(s):  
Lower Bound ◽  
Extra Dimension ◽  
Higgs Mass ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Quartic Coupling ◽  
Muon Anomalous Magnetic Moment ◽  
Expectation Value ◽  
The Standard Model ◽  
Standard Model Result

We investigate the Randall–Sundrum model with a light stabilized radion (required to fix the size of the extra dimension) in the light of muon anomalous magnetic moment [Formula: see text]. Using the recent data (obtained from the E821 experiment of the BNL Collaboration) which differs by 2.6σ from the Standard Model result, we obtain constraints on radion mass mϕ and radion vacuum expectation value 〈ϕ〉. In the presence of a radion the beta functions β(λ) and β(gt) of Higgs quartic coupling (λ) and top-Yukawa coupling (gt) gets modified. We find these modified beta functions. Using these beta functions together with the anomaly constrained mϕ and 〈ϕ〉, we obtain lower bound on Higgs mass mh. We compare our result with the present LEP2 bound on mh.

scholarly journals UTILITY OF A SPECIAL SECOND SCALAR DOUBLET

2008 ◽  
Vol 23 (09) ◽  
pp. 647-652 ◽  
Author(s):  
ERNEST MA
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Neutrino Mass ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Grand Unification ◽  
Particle Interactions ◽  
Expectation Value ◽  
The Standard Model

This review deals with the recent resurgence of interest in adding a second scalar doublet (η+, η0) to the Standard Model of particle interactions. In most studies, it is taken for granted that η0 should have a nonzero vacuum expectation value, even if it may be very small. What if there is an exactly conserved symmetry which ensures 〈η0 〉 = 0? The phenomenological ramifications of this idea include dark matter, radiative neutrino mass, leptogenesis, and grand unification.

INFLUENCE OF CHARGINOS AND NEUTRALINOS ON THE ANOMALOUS MAGNETIC MOMENT OF THE MUON WITH AND WITHOUT R-PARITY BREAKING

1992 ◽  
Vol 07 (04) ◽  
pp. 279-292 ◽  
Author(s):  
HEINZ KÖNIG
Keyword(s):  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Detailed Calculation ◽  
Expectation Value ◽  
Tau Neutrino ◽  
Parity Breaking

We present a detailed calculation of the contribution ∆aμ to the anomalous magnetic moment of the muon, when charginos and neutralinos are taken into account inside the relevant penguin diagrams. We consider the minimal supersymmetric standard model and include spontaneous R-parity breaking through the vacuum expectation value ντ of the scalar tau neutrino [Formula: see text]. We show that R-parity breaking leads to a result for Δaμ, which is less than a factor 10 below the experimental value.

scholarly journals FERMION-BOSON LOOPS WITH BILINEAR R-PARITY VIOLATION LEADING TO MAJORANA NEUTRINO MASS AND MAGNETIC MOMENTS

2008 ◽  
Vol 17 (01) ◽  
pp. 276-281 ◽  
Author(s):  
MAREK GÓŹDŹ ◽  
WIESŁAW A. KAMIŃSKI
Keyword(s):  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Minimal Supersymmetric Standard Model ◽  
Parity Violation ◽  
Magnetic Moments ◽  
Majorana Neutrino ◽  
Feynman Diagrams ◽  
Neutrino Masses ◽  
Analytic Expressions ◽  
Majorana Neutrino Mass

We present analytic expressions corresponding to a set of one loop Feynman diagrams, built within R-parity violating (RpV) minimal supersymmetric standard model (MSSM). Diagrams involve both bilinear and trilinear RpV couplings and represent Majorana neutrino masses and magnetic moments.

scholarly journals Electroweak Phase Transitions in Einstein’s Static Universe

2018 ◽  
Vol 2018 ◽  
pp. 1-5
Author(s):  
M. Gogberashvili
Keyword(s):  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Electroweak Phase Transition ◽  
Static Universe ◽  
Expectation Value ◽  
First Order ◽  
Higgs Vacuum ◽  
The Standard Model ◽  
Effective Reduction ◽  
New Phase

We suggest using Einstein’s static universe metric for the metastable state after reheating, instead of the Friedman-Robertson-Walker spacetime. In this case, strong static gravitational potential leads to the effective reduction of the Higgs vacuum expectation value, which is found to be compatible with the Standard Model first-order electroweak phase transition conditions. Gravity could also increase the CP-violating effects for particles that cross the new phase bubble walls and thus is able to lead to the successful electroweak baryogenesis scenario.

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