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- The Heavy Neutral Higgs Signature in the gammagamma __> ZZ Process doi link

Auteur(s): Gounaris G.J., Renard F. M., Porfyriadis P.I.

(Article) Publié: European Physical Journal C, vol. p.57-76 (2001)
Texte intégral en Openaccess : arXiv


Ref Arxiv: hep-ph/0010006
DOI: 10.1007/s100520100589
Ref. & Cit.: NASA ADS
12 citations
Résumé:

If the standard model (SM) Higgs particle is sufficiently heavy, then its contribution to $\gamma \gamma \to Z Z $ should be largely imaginary, interfering with the also predominantly imaginary SM "background"generated by the W loop. For standard model Higgs masses in the region $200\lesssim m_H \lesssim 500$ GeV, this interference is found to be constructive and increasing the Higgs signal. In the minimal SUSY case an interference effect should also appear for the contribution of the heavier CP-even neutral Higgs boson H0, provided it is sufficiently heavy. The effect is somewhat reduced, though, by the smallness of the H0 width and the $\gamma\gamma$ and ZZ branching ratios. The interference is again found to be constructive for part of the parameter space corresponding to sfermion masses at the TeV scale and maximal stop mixing. For both the SM and the SUSY case, regions of the parameter space exist, though, where the interference may be destructive. It is therefore essential to take these effects into account when searching for possible scalar Higgs-like candidates. To this aim, we present the complete analytic expressions for both resonance and background amplitudes.