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7 papers found.
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Dark matter from strong dynamics: the minimal theory of dark baryons

Abstract As a simple model for dark matter, we propose a QCD-like theory based on SU(2) gauge theory with one flavor of dark quark. The model is confining at low energy and we use lattice simulations to investigate the properties of the lowest-lying hadrons. Compared to QCD, the theory has several peculiar differences: there are no Goldstone bosons or chiral symmetry restoration...

Modeling Possible Cooling-Water Intake System Impacts on Ohio River Fish Populations

To assess the possible impacts caused by cooling-water intake system entrainment and impingement losses, populations of six target fish species near power plants on the Ohio River were modeled. A Leslie matrix model was constructed to allow an evaluation of bluegill, freshwater drum, emerald shiner, gizzard shad, sauger, and white bass populations within five river pools. Site...

αs from the Hadronic Vacuum Polarisation

We present our result for the strong coupling constant computed from the u-d vector Hadronic Vacuum Polarisation function. We use nf = 2 + 1 flavours of Domain Wall fermions at 3 lattice spacings, generated by the RBC-UKQCD collaboration. We identify several possible pitfalls in this method for determining the coupling and illustrate how to resolve them.

More on heavy tetraquarks in lattice QCD at almost physical pion mass

We report on our progress in studying exotic, heavy tetraquark states, qq′ Q̅Q̅′. Using publicly available dynamical nf = 2 + 1 Wilson-Clover gauge configurations, generated by the PACS-CS collaboration, with pion masses ≃ 164, 299 and 415 MeV, we extend our previous analysis to heavy quark components containing heavier than physical bottom quarks Q̅Q̅′ = b̅′b̅′ or Q̅Q̅′ = b̅b...

Composite Goldstone dark matter: experimental predictions from the lattice

We study, via lattice simulations, the nonperturbative dynamics of SU(2) gauge theory with two fundamental Dirac flavors. The model can be used simultaneously as a template for composite Goldstone boson dark matter and for breaking the electroweak symmetry dynamically. We compute the form factor, allowing us to estimate the associated electromagnetic charge radius. Interestingly...

Fundamental composite Higgs dynamics on the lattice: SU(2) with two flavors

Ari Hietanen Randy Lewis 1 Claudio Pica Francesco Sannino 0 -Origins & the Danish IAS, University of Southern Denmark , Campusvej 55, DK-5230 Odense M, Denmark 1 Department of Physics and

It is a graviton! or maybe not

Abstract The discovery of Kaluza-Klein (KK) gravitons is a smoking gun of extra dimensions. Other scenarios, however, could give rise to spin-two resonances of a new stronglycoupled sector and act as impostors. In this paper we prove that a spin-two resonance does not couple to the Standard Model through dimension-four operators. We then show that the massive graviton and its...