Scattering of dark pions in an Sp(4)-gauge theory

In this work we consider strongly interacting dark matter candidates as composite states of Nf=2 fermions charged under a dark Sp(4) gauge group in the fundamental representation. We give expressions that allow the calculation of correlation functions of two pseudo-Nambu-Goldstone-bosons with lattice field theory and present first results on the scattering phase shift in the isospin-2 channel in the theory from first principles. We give a lower limit on the dark matter particle mass by comparing our results with astrophysical constraints on the cross-section

Dependence of the Landau gauge ghost-gluon-vertex on the number of flavors

The gauge-boson, ghost and fermion propagators as well as the gauge-boson–ghost vertex functionare studied for SU(N ), Sp(2N ) and SO(N ) gauge groups. We solve a set of coupled Dyson-Schwingerequations in Landau gauge for a variable, fractional number Nf of massless fermions in the funda-mental representation. For large Nf we find a phase transition from a chirally broken into a chirallysymmetric phase that is consistent with the behavior expected inside the conformal window. Evenin the presence of fermions the gauge-boson–ghost-vertex dressing remains small. In the conformalwindow this vertex shows the expected power law behavior. It does not assume its tree-level valuein the far infrared, but the respective dressing function is a constant greater than on

Scattering of dark pions in an Sp(4) gauge theory

In this work we consider strongly interacting dark matter candidates as composite states of $N_f=2$ fermions charged under a dark $Sp(4)$ gauge group in the fundamental representation. We give expressions that allow the calculation of correlation functions of two pseudo-Nambu-Goldstone-bosons with lattice field theory and present first results on the scattering phase shift in the isospin-2 channel in the theory from first principles. We give a lower limit on the dark matter particle mass by comparing our results with astrophysical constraints on the cross-section.Comment: 7 pages, 2 figures, The 40th International Symposium on Lattice Field Theory (Lattice 2023