Clockwork Higgs portal model for freeze-in dark matter

Abstract

The clockwork mechanism can explain interactions which are dimensionally very weak without the need for very large mass scales. We present a model in which the clockwork mechanism generates the very small Higgs portal coupling and dark matter particle mass necessary to explain cold dark matter via the freeze-in mechanism. We introduce a TeV-scale scalar clockwork sector which couples to the Standard Model via the Higgs portal. The dark matter particle is the lightest scalar of the clockwork sector. We show that the freezein mechanism is dominated by decay of the heavy clockwork scalars to light dark matter scalars and Higgs bosons. In the model considered, we find that freeze-in dark matter is consistent with the clockwork mechanism for global charge q in the range 2 ≲ q ≲ 4 when the number of massive scalars is in the range 10 ≤ N ≤ 20. The dark matter scalar mass and portal coupling are independent of q and N. For a typical TeV-scale clockwork sector, the dark matter scalar mass is predicted to be of the order of a MeV.

The clockwork supergravity

“…Some applications of the clockwork mechanism have been worked out in a series of recent papers [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18].…”

Clockworked VEVs and neutrino mass

“…It can be generated by deconstruction of the extra dimension on a discrete lattice [8]. The clockwork mechanism has been applied to wide class of scenarios that necessitates small couplings, for example, axion physics [7,8,[17][18][19], dark matter scenarios [20][21][22][23], inflation [5,24,25], neutrino mass and flavour hierarchy [26][27][28], relaxion models [6,29,30] etc.…”

General continuum clockwork

“…To get the continuum limit of the lagrangian densities (2.1) and (2.3), one can make the following substitutions: 19) together with the field and parameter redefinitions: 20) JHEP07 (2018)113 and finally take the limit ∆r → 0. One then finds…”

“…Among the many possible implementations of the mechanism [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23], the CW axions [2,3] and U(1) gauge bosons [4,5] are particularly interesting as the key features of the mechanism can be understood in terms of a specific pattern of symmetry breaking of the underlying N + 1 (global or local) U(1) symmetries [U (1)] N +1 = N i=0 U(1) i , which is (explicitly or spontaneously) broken down to a U(1) CW subgroup. Furthermore, the key model parameters such as the CW parameter q and the involved axion-instanton couplings and U(1) gauge charges, are required to be integervalued (in appropriate units) by the compact [U (1)] N +1 , so the model has a built-in criterion for natural size of these model parameters.…”