The Higgs Boson Lineshape
Abstract
The current searches for a heavy Higgs boson assume on-shell (stable) Higgs-boson production. The Higgs-boson production cross section is then sampled with a Breit-Wigner distribution (with fixed-width or running-width) and implemented in MonteCarlo simulations. Therefore the question remains of what is the limitation of the narrow Higgs-width approximation. The main focus of this work is on the description of the Standard Model Higgs--boson-lineshape in the heavy Higgs region, typically above . The framework discussed in this paper is general enough and can be used for all processes and for all kinematical regions. Numerical results are shown for the gluon-fusion process. Issues of gauge invariance and residual theoretical uncertainties are also discussed. Limitations due to a breakdown of the perturbative expansion are comprehensively discussed, including a discussion of th equivalence theorem for (off-shell) virtual vector-bosons. Analytic continuation in a theory with unstable particles is thoroughly discussed.
Cite
@article{arxiv.1112.5517,
title = {The Higgs Boson Lineshape},
author = {Stefano Goria and Giampiero Passarino and Dario Rosco},
journal= {arXiv preprint arXiv:1112.5517},
year = {2015}
}
Comments
51 pages, 16 eps figures, v2 a major extension to our previous work