Dark matter interacting via a massive spin-2 mediator in warped extra-dimensions

Abstract

We study dark matter interacting via a massive spin-2 mediator. To have a consistent effective theory for the spin-2 particle, we work in a warped extra-dimensional model such that the mediator(s) are the Kaluza-Klein (KK) modes of the 5D graviton. We pay close attention to dark matter annihilations into KK-gravitons. Due to the high energy behavior of longitudinal modes of spin-2 fields, these channels exhibit a tremendous growth at large center of mass energies $$ \sqrt{s} $$ s if only one spin-2 mediator is considered. For the first time, we include the full KK-tower in this dark matter production process and find that this growth is unphysical and cancels once the full field content of the extra-dimensional theory is taken into account. Interestingly, this implies that it is not possible to approximate the results obtained in the full theory with a reduced set of effective interactions once $$ \sqrt{s} $$ s is greater than the first graviton mass. This casts some doubt on the universal applicability of previous studies with spin-2 mediators within an EFT framework and prompts us to revisit the phenomenological allowed parameter space of gravitationally interacting scalar dark matter in warped extra-dimensions.

Erratum to: Gravity-mediated scalar Dark Matter in warped extra-dimensions

“…In agreement with ref. [2], we find that it is possible to reproduce the DM energy density via freeze-out and comply with all the constraints near the radion resonance, m DM m r /2 (we have taken m r = 1 TeV). In ref.…”

“…We show this particular value of m r here in order to compare more easily with the results of ref. [2]. Figure 1 (right panel), on the other hand, shows the region in the (m DM , m G 1 ) plane for which the observed DM relic abundance is obtained, together with experimental bounds from DM direct detection and LHC resonant KK-graviton searches, as well as theoretical constraints, namely the unitarity limit and the region where the perturbativity of the effective theory is doubtful.…”

“…In ref. [2], the authors reconsider gravity-mediated scalar Dark Matter within the Randall-Sundrum scenario, studied in this paper, and they find that once the summation over all the KK virtual gravitons is performed, the DM annihilation cross-section into KKgravitons is indeed subleading with respect to the annihilation into SM particles. This changes drastically our previous results, summarized in figure 10 of the paper.…”

“…After this article was published, we became aware of refs. [1,2], where it was shown that the fast growth of the scalar DM annihilation cross section into KK-gravitons for large DM mass (m DM m Gn ) is in fact an artifact of not summing over the full tower of KK-gravitons of the 5-dimensional theory. When one adds coherently to our result for the cross-section SS → G n G m in eq.…”

“…We refer the readers to refs. [1,2] for the technical details, and here we just have updated our plots using the corrected DM annihilation cross-section, now dominated by the SM final states. Notice that we restrict ourselves to the case in which the radion plays a role, since we find that otherwise it is not possible to reproduce the Dark Matter relic abundance in any point allowed by current LHC bounds and theoretical constraints.…”