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Updated: May 18, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Probing new physics via the B(s)0→μ(+)μ- effective lifetime.
Kristof De Bruyn1, Robert Fleischer, Robert Knegjens
1Nikhef, Science Park 105, NL-1098 XG Amsterdam, Netherlands.
Physical Review Letters
|September 26, 2012
Summary
New physics searches using B(s) meson decays are refined. The measured decay width difference ΔΓ(s) impacts branching ratio calculations and offers a new clean probe, the effective lifetime τ(μ(+)μ(-)), for discovering physics beyond the standard model.
Area of Science:
- High Energy Physics
- Particle Physics
- Cosmology
Background:
- New upper bounds for B(s)(0)→μ(+)μ(-) branching ratio are established.
- A non-vanishing decay width difference ΔΓ(s) in the B(s) system has been experimentally measured.
Purpose of the Study:
- To investigate the impact of ΔΓ(s) on the extraction of the B(s)(0)→μ(+)μ(-) branching ratio.
- To develop formulas for incorporating the effect of ΔΓ(s) into new physics parameter space constraints.
- To introduce and analyze the effective B(s)(0)→μ(+)μ(-) lifetime τ(μ(+)μ(-)) as a new observable for new physics searches.
Main Methods:
- Theoretical analysis of B(s) meson decay dynamics.
- Derivation of formulas to include ΔΓ(s) effects in branching ratio calculations.
- Formulation of the effective lifetime observable τ(μ(+)μ(-)).
Main Results:
- The decay width difference ΔΓ(s) significantly affects the extraction of the B(s)(0)→μ(+)μ(-) branching ratio.
- Formulas are provided to accurately account for ΔΓ(s) in new physics searches.
- The effective lifetime τ(μ(+)μ(-)) is proposed as a theoretically clean probe for new physics, complementary to the branching ratio.
Conclusions:
- Accurate extraction of the B(s)(0)→μ(+)μ(-) branching ratio requires considering ΔΓ(s).
- The effective lifetime τ(μ(+)μ(-)) offers a novel and sensitive method for discovering new physics, even if the branching ratio aligns with standard model predictions.
- Future measurements of τ(μ(+)μ(-)) at upgraded Large Hadron Collider experiments could reveal substantial new physics effects.
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