相关论文: Positronium Decays with Dark $Z$ and Fermionic Dar…
In this letter, we consider a class of scenarios in which the dark matter is part of a heavy hidden sector that is thermally decoupled from the Standard Model in the early universe. The dark matter freezes-out by annihilating to a lighter,…
We discuss positronium decays with emphasis on tests of fundamental symmetries and the constraints from measurements of other precision observables involving electrons and photons.
We explore the possibility that $Z'$ couplings can be probed using decay modes which involve neutrinos once Standard Model backgrounds are directly determined by the data itself. For some models, sufficient statistics are available at…
We discuss novel ways in which neutrino oscillation experiments can probe dark matter. In particular, we focus on interactions between neutrinos and ultra-light ("fuzzy") dark matter particles with masses of order $10^{-22}$ eV. It has been…
The possibility of direct detection of light fermionic dark matter in neutrino detectors is explored from a model-independent standpoint. We consider all operators of dimension six or lower which can contribute to the interaction $\bar{f} p…
Supersymmetry can explain the observed dark matter relic density with a neutralino dark matter particle and a coannihilating, almost mass-degenerate sparticle. If this were the case in nature, a linear electron positron collider like the…
The indirect detection of dark matter annihilation and decay using observations of photons, charged cosmic rays, and neutrinos offers a promising means of identifying the particle nature of this elusive component of the universe. The last…
We study radiative decay modes of the Z-boson into heavy quark bound states. We find that the widths for these decays are extremely small. We conclude that these decays will not be detectable for the time being unless there is a significant…
Assuming Galactic positrons do not go far before annhilating, a difference between the observed 511 keV annihilation flux distribution and that of positron production, expected from beta-plus decay in Galactic iron nucleosynthesis, was…
We present a calculation of the branching ratio of orthopositronium decay into an invisible mode, which is done in the context of Mirror World models, where ordinary positronium can disappear from our world due to oscillation into its…
Detection of a surprisingly high flux of positron annihilation radiation from the inner galaxy has motivated the proposal that dark matter is made of weakly interacting light particles (possibly as light as the electron). This scenario is…
The article describes Boltzmann equations for a potential case of multi-particle dark matter with symmetric and asymmetric dark matter components in a model-independent approach. We focus on the specific scenario where one of the DM…
The cold dark matter may be in a meta-stable state and decays to other particles with a very long lifetime. If the decaying products of the dark matter are weakly interacting, e.g. neutrinos, then it would have little impact on…
We study flavor changing neutral current decays of $B$ and $K$ mesons in the dark $U(1)_D$ model, with the dark photon/dark $Z$ mass between 10 MeV and 2 GeV. Although the model provides an improved fit (compared to the standard model) to…
A light fermionic weakly interacting massive particle (WIMP) dark matter is investigated by studying its minimal renormalizable model, where it requires a scalar mediator to have an interaction between the WIMP and standard model particles.…
We investigate constraints on the interactions of light dark matter with Standard Model quarks in a framework with effective contact operators mediating the decay of heavy flavor bound state quarkonium to dark matter and a photon. When…
Observational manifestations of possible breaking of spin-statistics relation for neutrinos are considered. It is argued that bosonic neutrinos may form cosmological cold dark matter, improve agreement of BBN predictions with observations,…
We examine in a model-independent manner the measurements that can be performed at B-factories with sensitivity to dark matter. If a singlet scalar, pseudo-scalar, or vector is present and mediates the Standard Model - dark matter…
We revisit dark matter annihilation as an explanation of the positron excess reported recently by the AMS-02 satellite-borne experiment. To this end, we propose a particle dark matter model by considering a Two Higgs Doublet Model (2HDM)…
In the first part of this note, we observe that a non-Riemannian piece in the affine connection (a "dark connection") leads to an algebraically determined, conserved, symmetric 2-tensor in the Einstein field equations that is a natural dark…