We study the constraints on neutralino dark matter in minimal low energy supersymmetry models and the case of heavy lepton and quark scalar superpartners.
For values of the Higgsino and gaugino mass parameters of the order of the weak
scale, direct detection experiments are already putting strong bounds on models
in which the dominant interactions between the dark matter candidates and...
We study an MSSM scenario in which the only light sparticles are a bino-like
dark matter candidate, and one or more light-flavored squarks. We find that this
scenario has several interesting phenomenological features. In particular, LHC
searches for the light squarks have reduced sensitivity, since the visible and
invisible products tend to be softer. Moreover, bino-squark co-annihilation...
The most dramatic "Sommerfeld enhancements" of neutral-wino-pair annihilation occur when the wino mass is tuned to near critical values where there is a zero-energy S-wave resonance at the neutral-wino-pair threshold. If the wino mass is larger than the critical value, the resonance is a wino-pair bound state. If the wino mass is near a critical value, low-energy winos can be described by a...
The spectrum of Weakly-Interacting-Massive-Particle (WIMP) dark matter generically possesses bound states when the WIMP mass becomes sufficiently large relative to the mass of the electroweak gauge bosons. The presence of these bound states enhances the annihilation rate via resonances in the Sommerfeld enhancement, but they can also be produced directly with the emission of a low-energy...
We study a multi-component dark matter model where interactions with the Standard Model are primarily via the Higgs boson. The model contains vector-like fermions charged under SU(2)W × U(1)Y and under the dark gauge group, U(1)′. This results in two dark matter candidates. A spin-1 and a spin-1/2 candidate, which have loop and tree-level couplings to the Higgs, respectively. We explore the...
Fermionic dark matter is added to the Froggatt-Nielsen mechanism, and conditions for freezeout identified. DM is charged under $U(1)_{FN}$, with the dominant annihilation channel a CP-even flavon $+$ CP-odd flavon. When the DM-flavon coupling strength $\sim$ the Cabibbo angle (0.23): (1) the DM mass is $\mathcal{O}$(100 GeV - 1 TeV), (2) perturbativity puts a lower and upper limits on the...
Identifying signatures of dark matter at indirect-detection experiments is generally more challenging in non-minimal dark-matter scenarios than it is in scenarios involving a single dark particle. The reason is that the partitioning of the total dark-matter abundance across an ensemble of particles with different masses tends to "smear" the injection spectra of photons and other cosmic-ray...
In the Dynamical Dark Matter (DDM) framework, the dark sector comprises a vast ensemble of particle species whose Standard-Model decay widths are balanced against their cosmological abundances. In this talk, we present a new class of DDM ensembles in which the masses of the dark states lie along linear Regge trajectories and the density of dark states grows exponentially with mass. Ensembles...
