Lowering alpha_s by flipping SU(5)

Abstract

We show that the prediction for ${\alpha }_s(M_Z)$ in flipped SU(5) is naturally lower than in minimal SU(5), and that the former can accommodate the full range of ${\alpha }_s(M_Z)$ presently allowed by experiment. Our computations include two-loop (${\delta }_{2loop}$) and light (${\delta }_{\mathrm{light}}$) and heavy (${\delta }_{\mathrm{heavy}}$) threshold effects. Unlike minimal SU(5), in flipped SU(5) the heavy threshold effects can naturally decrease the predicted value of ${\alpha }_s(M_Z)$. We also show that the value of the proton lifetime into the dominant channel $p\to e^{+}{\pi }^0$ is within the observable range at SuperKamiokande, and should discriminate against minimal supersymmetric SU(5), where the dominant mode is $p\to \bar{\nu }{K}^{+}$.

11 pages, LaTeX, 2 figures (uuencoded)

References in corpus (6)

• Observation of the Top Quark
• Precision Corrections to Supersymmetric Unification
• Precision determination of ${\alpha }_s$ and $m_b$ from QCD sum rules for $b\overline{b}$.
• ${\sin }^2{\theta }_W(M_Z)$ ~in the MSSM and Unification of Couplings
• Determining ${\alpha }_s$ from Measurements at $Z$: How Nature Prompts us about New Physics
• A Global Fit of LEP/SLC Data with Light Superpartners

Cited by in corpus (29)

• How generic is cosmic string formation in SUSY GUTs
• Not Even Decoupling Can Save Minimal Supersymmetric SU(5)
• Search for Proton Decay via p -> e+ pi0 in a Large Water Cherenkov Detector
• WMAPing the Universe: Supersymmetry, Dark Matter, Dark Energy, Proton Decay and Collider Physics
• Suggested new modes in supersymmetric proton decay
• Beyond the CMSSM without an Accelerator: Proton Decay and Direct Dark Matter Detection
• Deriving Models for keV sterile Neutrino Dark Matter with the Froggatt-Nielsen mechanism
• Flipping SU(5) out of Trouble
• Elements of F-ast Proton Decay
• Dark Matter, Proton Decay and Other Phenomenological Constraints in $\mathcal{F}$-SU(5)
• Fast Proton Decay
• Proton Decay: Flipped vs Unflipped SU(5)
• Leptophobic $Z^{\prime }$ in stringy flipped SU(5)
• SO(10) GUT in Four and Five Dimensions: A Review
• Observable Proton Decay in Flipped SU(5)
• A 125.5 GeV Higgs Boson in F-SU(5): Imminently Observable Proton Decay, A 130 GeV Gamma-ray Line, and SUSY Multijets & Light Stops at the LHC8
• On Supersymmetric b-tau Unification, Gauge Unification, and Fixed Points
• Hypercharge and baryon minus lepton number in E6
• Supersymmetry: From the Fermi Scale to the Planck Scale
• Realizing unification in two different SO(10) models with one intermediate breaking scale
• Experimental study of the atmospheric neutrino backgrounds for proton decay to positron and neutral pion searches in water Cherenkov detectors
• The Diboson Excesses in Leptophobic $U(1{)}_{\mathrm{LP}}$ Models from String Theories
• Experimental constraints on a stringy SU(5)$\times$U(1) model
• Moderately Suppressed Dimension-five Proton Decay in a Flipped $SU(5)$ Model
• Alpha_s and Gauge Coupling Unification in Flipped SU(5) Models with Gauge-Mediated Supersymmetry Breaking
• Application of Pade Approximants to Determination of alpha_s(M_Z^2) from Hadronic Event Shape Observables in e+e- Annihilation
• String Unification and Leptophobic $Z^{\prime }$ in Flipped SU(5)
• Seesaw scales and the steps from the Standard Model towards superstring-inspired flipped E_6
• Randall-Sundrum and Flipped SU(5)