9,331 research outputs found
Unitarity constraints on chiral perturbative amplitudes
Low lying scalar resonances emerge as a necessary part to adjust chiral
perturbation theory to experimental data once unitarity constraint is taken
into consideration. I review recent progress made in this direction in a model
independent approach. Also I briefly review studies on the odd physical
properties of these low lying scalar resonances, including in the
processes.Comment: Talk given at: International Workshop on Effective Field Theories:
from the pion to the upsilon, February 2-6 2009, Valencia, Spai
Categorical traces and a relative Lefschetz-Verdier formula
We prove a relative Lefschetz-Verdier theorem for locally acyclic objects
over a Noetherian base scheme. This is done by studying duals and traces in the
symmetric monoidal -category of cohomological correspondences. We show that
local acyclicity is equivalent to dualizability and deduce that duality
preserves local acyclicity. As another application of the category of
cohomological correspondences, we show that the nearby cycle functor over a
Henselian valuation ring preserves duals, generalizing a theorem of Gabber.Comment: 26 pages. v3: minor improvement
Scalar resonance at 750 GeV as composite of heavy vector-like fermions
We study a model of scalars which includes both the SM Higgs and a scalar
singlet as composites of heavy vector-like fermions. The vector-like fermions
are bounded by the super-strong four-fermion interactions. The scalar singlet
decays to SM vector bosons through loop of heavy vector-like fermions. We show
that the surprisingly large production cross section of di-photon events at 750
GeV resonance and the odd decay properties can all be explained. This model
serves as a good model for both SM Higgs and a scalar resonance at 750 GeV.Comment: 12 pages, no figure, references updated, version for publicatio
- …