Probing light thermal dark matter with a Higgs portal mediator

By G. Krnjaic. 2015

247 citations recorded by the source corpus.

We systematically study light (< few GeV) Dark Matter (DM) models that thermalize with visible matter through the Higgs portal and identify the remaining gaps in the viable parameter space. Such models require a comparably light scalar mediator that mixes with the Higgs to avoid DM overproduction and can be classified according to whether this mediator decays (in)visibly. In a representative benchmark model with Dirac fermion DM, we find that, even with conservative assumptions about the DM-mediator coupling and mass ratio, the regime in which the mediator is heavier than the DM is fully ruled out by a combination of collider, rare meson decay, and direct detection limits; future and planned experiments including NA62 can further improve sensitivity to scenarios in which the Higgs portal interaction does not determine the DM abundance. The opposite, regime in which the mediator is lighter than the DM and the latter annihilates to pairs of visibly-decaying mediators is still viable, but much of the parameter space is covered by rare meson decay, supernova cooling, beam dump, and direct detection constraints. Nearly all of these conclusions apply broadly to the simplest variations (e.g. scalar or asymmetric DM). Future experiments including SHiP, NEWS, and Super-CDMS SNOLAB can greatly improve coverage to this class of models.

Subfields: Acoustics and Ultrasonics, Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/a8382f7a08ef938a921fdc67365ec8b77dc6a8dd

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Acoustics and Ultrasonics

1. Tongyan Lin
2. S. Knapen
3. Miguel Escudero

In Astronomy and Astrophysics

1. Tongyan Lin
2. M. Fairbairn
3. Miguel Escudero
4. S. Knapen
5. K. Zurek
6. J.B.G. Alvey
7. N. Sabti
8. D. Blas

In Nuclear and High Energy Physics

1. Tongyan Lin
2. K. Zurek
3. S. Knapen
4. P. Schuster
5. M. Fairbairn
6. D. Curtin
7. Miguel Escudero
8. D. Blas

Citations in the corpus

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• Light dark matter: Models and constraints (2017, background): “Note that these constraints have significant overlap with Higgs mixing models, which were considered recently in the context of thermal dark matter with mχ > 1 MeV [56].”
• Physics beyond colliders at CERN: beyond the Standard Model working group report (2019, background): “Most viable dark matter models in the sub-EW scale range imply 2 ·mχ > mS [29].”
• Dark matter models and direct detection (2019, background): “For the scalar Higgs portal mediator specifically, dark sector models are only viable in the mass range mχ &MeV and for mφ < mχ [123] (assuming no additional hidden sector states beyond the mediator and DM).”
• Refined bounds on MeV-scale thermal dark sectors from BBN and the CMB (2019, background): “[28] G.”