Limits on Low Scale Gravity from $e^+ e^- \to W^+ W^-, ZZ$ and $γγ$

K. Agashe; N. G. Deshpande

doi:10.1016/s0370-2693(99)00432-3

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arXiv · hep-ph/9902263

Limits on Low Scale Gravity from $e^+ e^- \to W^+ W^-, ZZ$ and $γγ$

K. Agashe·N. G. Deshpande

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Abstract

It has been proposed recently that the scale of quantum gravity (``the string scale'') can be $M_S \sim$ few TeV with $n \geq 2$ extra dimensions of size $R \stackrel{<}{\sim}$ mm so that, at distances greater than $R$, Newtonian gravity with $M_{Pl} \sim 10^{18}$ GeV is reproduced if $M_{Pl}^2 \sim R^n M_S^{n+2}$. Exchange of virtual gravitons in this theory generates higher-dimensional operators involving SM fields, suppressed by powers of $M_S$. We discuss constraints on this scenario from the contribution of these operators to the processes $e^+ e^- \to W^+ W^-, ZZ, γγ$. We find that LEP2 can place a limit $M_S \approx 1$ TeV from $e^+ e^- \to W^+ W^-, ZZ, γγ$.

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K. Agashe, N. G. Deshpande. 1999-03-19. Limits on Low Scale Gravity from $e^+ e^- \to W^+ W^-, ZZ$ and $γγ$. https://doi.org/10.1016/s0370-2693(99)00432-3

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