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Updated: Jun 26, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
S parameter and pseudo Nambu-Goldstone boson mass from lattice QCD
1High Energy Accelerator Research Organization (KEK), Tsukuba 305-0801, Japan.
Physical Review Letters
|December 31, 2008
Summary
We calculated key parameters for chiral perturbation theory using lattice calculations. These results help distinguish between technicolor models by determining the S parameter and pseudo Nambu-Goldstone boson mass.
Area of Science:
- * Lattice Quantum Chromodynamics (LQCD)
- * High Energy Physics
- * Theoretical Particle Physics
Background:
- * Chiral perturbation theory describes low-energy interactions of quarks and mesons.
- * Technicolor models propose new strong dynamics beyond the Standard Model.
- * Distinguishing between technicolor models requires precise theoretical predictions.
Purpose of the Study:
- * To perform a lattice calculation of the low-energy constant L10.
- * To compute the charged-neutral pion squared-mass splitting.
- * To assess the utility of lattice techniques for technicolor model discrimination.
Main Methods:
- * Employed dynamical overlap fermion for lattice calculations.
- * Utilized the exact chiral symmetry of overlap fermions.
- * Analyzed the difference between vector and axial-vector current vacuum polarization functions.
Main Results:
- * Determined the value of L10, a low-energy constant.
- * Calculated the charged-neutral pion squared-mass splitting.
- * Demonstrated the connection of these quantities to technicolor model parameters.
Conclusions:
- * The lattice calculation successfully extracted L10 and the pion mass splitting.
- * These results provide crucial data for discriminating technicolor models.
- * The employed lattice techniques are feasible for broader technicolor gauge theory studies.
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