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arXiv · hep-ph/0001335

Fat Brane Phenomena

A. De Rujula·A. Donini·M. B. Gavela·S. Rigolin
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Abstract

Gravitons could permeate extra space dimensions inaccessible to all other particles, which would be confined to ``branes''. We point out that these branes could be ``fat'' and have a non-vanishing width in the dimensions reserved for gravitons. In this case the other particles, confined within a finite width, should have ``branon'' excitations. Chiral fermions behave differently from bosons under dimensional reduction, and they may --or may not-- be more localized than bosons. All these possibilities are in principle testable and distinguishable, they could yield spectacular signatures at colliders, such as the production of the first branon excitation of $γ$'s or $Z$'s, decaying into their ground state plus a quasi-continuum of graviton recurrences. We explore these ideas in the realm of a future lepton collider and we individuate a {\it dimensiometer}: an observable that would cleanly diagnose the number of large ``extra'' dimensions.

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A. De Rujula, A. Donini, M. B. Gavela, S. Rigolin. 2000-02-14. Fat Brane Phenomena. https://doi.org/10.1016/s0370-2693(00)00479-2

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