We describe two natural scenarios in which both dark matter WIMPs (weakly interacting massive particles) and a variety of supersymmetric partners should be discovered in the foreseeable future. In the first scenario, the WIMPs are neutralinos, but they are only one component of the dark matter, which is dominantly composed of other relic particles such as axions. (This is the multicomponent model of Baer, Barger, Sengupta, and Tata.) In the second scenario, the WIMPs result from an extended Higgs sector and may be the only dark matter component. In either scenario, both the dark matter WIMP and a plethora of other neutral and charged particles await discovery at many experimental facilities. The new particles in the second scenario have far weaker cross-sections for direct and indirect detection via their gauge interactions, which are either momentum-dependent or second-order. However, as we point out here, they should have much stronger interactions via the Higgs. We estimate that their interactions with fermions will then be comparable to (although not equal to) those of neutralinos with a corresponding Higgs interaction. It follows that these newly proposed dark matter particles should be within reach of emerging and proposed facilities for direct, indirect, and collider-based detection.

The WIMP proposed here yields the observed abundance of dark matter, and is consistent with the current limits from direct detection, indirect detection, and collider experiments, if its mass is ∼ 72 GeV/c 2 . It is also consistent with analyses of the gamma rays observed by Fermi-LAT from the Galactic center (and other sources), and of the antiprotons observed by AMS-02, in which the excesses are attributed to dark matter annihilation. These successes are shared by the inert doublet model (IDM), but the phenomenology is very different: the dark matter candidate of the IDM has first-order gauge couplings to other new particles, whereas the present candidate does not. In addition to indirect detection through annihilation products, it appears that the present particle can be observed in the most sensitive direct-detection and collider experiments currently being planned.

We consider the gauge couplings of a new dark matter candidate and find that they are comparable to those of a neutralino.

We review a dark matter scenario with a number of favorable aspects: (1) all of the well-known successes of supersymmetry are preserved, (2) the parameters can satisfy naturalness, (3) the addition of an extended Higgs sector implies a doubly rich plethora of new particles and new physics to be discovered in the near or foreseeable future, (4) the mass of the dominant dark matter WIMP is ≤ 125 GeV/c 2 , (5) the gauge couplings of this particle are precisely defined, and (6) naturalness implies that its Higgs-mediated couplings are also comparable to those of a natural neutralino. Recent (and earlier) analyses of the data from Planck, Fermi-LAT, AMS-02, and other experiments indicate that (i) the positron excess at ∼ 800 GeV or above is not evidence of highmass dark matter particles (which would have disconfirmed the present theory with a rigorous upper limit of 125 GeV), (ii) the Galactic center excess of gamma rays observed by Fermi is evidence for dark matter particles with a mass below or near 100 GeV, (iii) the gamma-ray excess from Omega Centauri is similar evidence of annihilation of such relatively low-mass particles, and (iv) the antiproton excess observed by AMS is again evidence of 100 GeV dark matter particles. The present scenario, with two stable spin 1/2 WIMPs (a high-mass neutralino and a more abundant "Higgson" with a mass of ≤ 125 GeV/c 2) is consistent with these results (as well as all others which have been verified), and it also suggests that detection should be near in a variety of experiments for direct, indirect, and collider detection.

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