In this work, we study the possibility that dark matter fields transform in the ð1; 0Þ ⊕ ð0; 1Þ representation of the homogeneous Lorentz group. In an effective theory approach, we study the lowest-dimension interacting terms of dark matter with standard model fields, assuming that dark matter fields transform as singlets under the standard model gauge group. There are three dimension-four operators, two of them yielding a Higgs portal to dark matter. The third operator couples the photon and Z 0 fields to the higher multipoles of dark matter, yielding a spin portal to dark matter. For low mass dark matter (D), the decays Z 0 →DD and H →DD are kinematically allowed and contribute to the invisible widths of the Z 0 and H bosons. We use experimental results on these invisible widths to constrain the values of the low-energy constants g t (for the spin portal) and g s , g p (for the Higgs portal) for this mass region. We calculate the dark matter relic density in our formalism and, using the above constraints, we find that consistency with the experimental value requires dark matter to have a mass M > 43 GeV in the case of the spin portal and M > 62 GeV for the Higgs portal. For higher mass dark matter (M > M H =2), we calculate the velocity averaged cross section for the annihilation of dark matter intobb and τ þ τ − and compare with the upper bounds recently reported by Fermi-LAT and DES Collaborations, finding that both portals yield results consistent with the reported upper bounds. Finally, we study direct detection by elastic scattering on nuclei. The Higgs portal yields results consistent with the upper bounds reported recently by the XENON Collaboration. The spin portal can also accommodate this data but requires higher values of the dark matter mass or smaller values of the corresponding coupling.

In this work we study the possibility that the gamma ray excess (GRE) at the Milky Way galactic center come from the annihilation of dark matter with a (1, 0) ⊕ (0, 1) space-time structure (spin-one dark matter, SODM). We calculate the production of prompt photons from initial state radiation, internal bremsstrahlung, final state radiation including the emission from the decay products of the µ, τ or hadronization of quarks. Next we study the delayed photon emission from the inverse Compton scattering (ICS) of electrons (produced directly or in the prompt decay of µ, τ leptons or in the hadronization of quarks produced in the annihilation of SODM) with the cosmic microwave background or starlight. All these mechanisms yield significant contributions only for Higgs resonant exchange, i.e. for M ≈ M H /2, and the results depend on the Higgs scalar coupling to SODM, g s. The dominant mechanism at the GRE bump is the prompt photon production in the hadronization of b quarks produced inDD →bb, whereas the delayed photon emission from the ICS of electrons coming from the hadronization of b quarks produced in the same reaction dominates at low energies (ω < 0.3 GeV) and prompt photons from c and τ , as well as from internal bremsstrahlung, yield competitive contributions at the end point of the spectrum (ω ≥ 30 GeV). Taking into account all these contributions, our results for photons produced in the annihilation of SODM are in good agreement with the GRE data for g s ∈ [0.98, 1.01]×10 −3 and M ∈ [62.470, 62.505] GeV. We study the consistency of the corresponding results for the dark matter relic density, the spin-independent dark matter-nucleon cross-section σ p and the cross section for the annihilation of dark matter intobb, τ + τ − , µ + µ − and γγ, taking into account the Higgs resonance effects, finding consistent results in all cases.

In this work we show that the excess of antiprotons in the range EK = 10 − 20 GeV reported by several groups in the analysis of the AMS-02 Collaboration data, can be explained by the production of antiprotons in the annihilation of dark matter with a (1, 0) ⊕ (0, 1) space-time structure (tensor dark matter). First, we calculate the proton and antiproton flux from conventional mechanisms and fit our results to the AMS-02 data, confirming the antiproton excess. Then we calculate the antiproton production in the annihilation of tensor dark matter. For the window M ∈ [62. 470, 62.505] GeV to which the measured relic density, XENO1T results and the gamma ray excess from the galactic center constrain the values of the tensor dark matter mass, we find sizable contributions of antiprotons in the excess region from the annihilation into bb and smaller contributions from the cc channel. We fit our results to the AMS-02 data, finding an improvement of the fit for these values of M .

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