Resonant and nonresonant new phenomena of four-fermion operators for experimental searches

Abstract

In the fermion content and gauge symmetry of the standard model (SM), we study the four-fermion operators in the torsion-free Einstein-Cartan theory. The collider signatures of irrelevant operators are suppressed by the high-energy cutoff (torsion-field mass) $\Lambda$, and cannot be experimentally accessible at TeV scales. Whereas the dynamics of relevant operators accounts for (i) the SM symmetry-breaking in the domain of infrared-stable fixed point with the energy scale $v\approx 239.5$ GeV and (ii) composite Dirac particles restoring the SM symmetry in the domain of ultraviolet-stable fixed point with the energy scale $\mathcal{E}\gtrsim 5$ TeV. To search for the resonant phenomena of composite Dirac particles with peculiar kinematic distributions in final states, we discuss possible high-energy processes: multi-jets and dilepton Drell-Yan process in LHC $pp$ collisions, the resonant cross-section in $e^{-}{e}^{+}$ collisions annihilating to hadrons and deep inelastic lepton-hadron $e^{-}p$ scatterings. To search for the nonresonant phenomena due to the form-factor of Higgs boson, we calculate the variation of Higgs-boson production and decay rate with the CM energy in LHC. We also present the discussions on four-fermion operators in the lepton sector and the mass-squared differences for neutrino oscillations in short baseline experiments.

16 pages, 2 figures, the version to appear in Phys. Lett. B

References in corpus (4)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• The phase structure of Einstein-Cartan theory
• Ultraviolet fixed point and massive composite particles in TeV scales

Cited by in corpus (8)

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• Hierarchy spectrum of SM fermions: from top quark to electron neutrino
• $W$ boson mass tension caused by its right-handed gauge coupling at high energies?
• Higgs boson origin from a gauge symmetric theory of massive composite particles and massless $W^{\pm }$ and $Z^0$ bosons at the TeV scale
• Spontaneous Peccei-Quinn symmetry breaking renders sterile neutrino, axion and $\chi$boson to be candidates for dark matter particles
• Critical fermion density for restoring spontaneously broken symmetry