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arXiv · 0709.4054

The process gg -> h_0 -> gamma gamma in the Lee-Wick Standard Model

Abstract

The process gg -> h_0 -> gamma gamma is studied in the Lee-Wick extension of the Standard Model (LWSM) proposed by Grinstein, O'Connell and Wise. In this model negative norm partners for each SM field are introduced with the aim to cancel quadratic divergences in the Higgs mass. All sectors of the model relevant to gg -> h_0 -> gamma gamma are diagonalized and results are commented on from the perspective of both the Lee-Wick and higher derivative formalisms. Deviations from the SM rate for gg -> h_0 are found to be of the order of 15% - 5% for Lee-Wick masses in the range 500GeV - 1000GeV. Effects on the rate for h_0-> gamma gamma are smaller, of the order of 5% - 1% for Lee-Wick masses in the same range. These comparatively small changes may well provide a means of distinguishing the LWSM from other models such as universal extra dimensions where same-spin partners to Standard Model fields also appear. Corrections to determinations of CKM elements |V_{t(b,s,d)}| are also considered and are shown to be positive, allowing the possibility of measuring a CKM element larger than unity, a characteristic signature of the ghost-like nature of the Lee-Wick fields.

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BibTeXRIS

F. Krauss, T. E. J. Underwood, R. Zwicky. 2011-01-20. The process gg -> h_0 -> gamma gamma in the Lee-Wick Standard Model. https://doi.org/10.1103/physrevd.77.015012

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