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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Proton decay and flavor violating thresholds in SO(10) models
Bhaskar Dutta1, Yukihiro Mimura, Rabindra N Mohapatra
1Department of Physics, Texas A&M University, College Station, Texas 77843-4242, USA.
Physical Review Letters
|June 4, 2008
Summary
Supersymmetric SO(10) models explain neutrino mass but face proton decay issues. Simple threshold effects can suppress proton decay by increasing Higgsino masses and the grand unification scale, resolving a key challenge.
Area of Science:
- Particle Physics
- Cosmology
- Grand Unification Theories
Background:
- Neutrino mass discovery highlights the supersymmetric SO(10) model for unifying forces and matter.
- A significant challenge in these models is suppressing proton decay to experimentally viable levels.
Purpose of the Study:
- To address the proton decay problem in supersymmetric SO(10) grand unified models.
- To explore methods for increasing the colored Higgsino masses and the grand unification scale.
Main Methods:
- Investigated simple threshold effects within the supersymmetric SO(10) framework.
- Analyzed specific SO(10) representations that can induce these threshold effects.
- Examined the impact on flavor violation in quark and lepton sectors.
Main Results:
- Demonstrated that threshold effects can raise colored Higgsino masses and the grand unification scale above 10^17 GeV, suppressing proton decay.
- Identified four types of fields from different SO(10) representations capable of generating these crucial threshold effects.
- Observed that some fields lead to significant flavor violation in the quark sector relative to the lepton sector.
Conclusions:
- The proposed threshold effects offer a viable solution to the proton decay problem in supersymmetric SO(10) models.
- These models can accommodate b-tau unification even with intermediate values of tanbeta.
- The findings provide a pathway for realistic grand unification theories incorporating neutrino mass.
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