S-channel dark matter simplified models and unitarity

Englert, C. , McCullough, M. and Spannowsky, M. (2016) S-channel dark matter simplified models and unitarity. Physics of the Dark Universe, 14, pp. 48-56. (doi: 10.1016/j.dark.2016.09.002)

Abstract

The ultraviolet structure of s-channel mediator dark matter simplified models at hadron colliders is considered. In terms of commonly studied s-channel mediator simplified models it is argued that at arbitrarily high energies the perturbative description of dark matter production in high energy scattering can break down. This is analogous to the well documented breakdown of an EFT description of dark matter collider production. With this in mind, to diagnose whether or not the use of simplified models at the LHC is valid, perturbative unitarity of the scattering amplitude in the processes relevant to LHC dark matter searches is studied. The results are as one would expect: at the LHC and future proton colliders the simplified model descriptions of dark matter production are in general valid. As a result of the general discussion, a simple class of ‘Fermiophobic Scalar’ simplified models is proposed, in which a scalar mediator couples to electroweak vector bosons. The Fermiophobic simplified model is well motivated and exhibits interesting collider and direct detection phenomenology.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Englert, Professor Christoph
• Authors: Englert, C., McCullough, M., and Spannowsky, M.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Physics of the Dark Universe
• Publisher: Elsevier
• ISSN: 2212-6864
• ISSN (Online): 2212-6864
• Published Online: 30 September 2016
• Copyright Holders: Copyright © 2016 Elsevier
• First Published: First published in Physics of the Dark Universe 14:48-56
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher