Singlet Mesons in Dark Sp(4) Theories
Abstract
We explore some aspects of $Sp(4)$ gauge theory with two fundamental fermions in the context of composite Goldstone Dark Matter. We present preliminary lattice results for the mass of the pseudoscalar iso-singlet meson $\eta'$ using unimproved Wilson fermions and the standard plaquette action. We find that the $\eta'$ is slightly heavier than the pseudoscalar non-singlets $\pi$ and lighter than the vector mesons $\rho$ for multiple ensembles with $m_\pi/m_\rho \geq 0.77$. This pattern is potentially relevant for Beyond the Standard Model physics model building. Furthermore, we show that for $N_f=1+1$ flavours the disconnected contributions to the unflavoured pseudoscalar $\pi^0$ are small. We supplement this measurement by a calculation of the $\pi\pi$ scattering length $a_0$ which shows that the ensemble studied might be phenomenologically relevant for Dark Matter models such as the Strongly Interacting Massive Particles paradigm.
- Publication:
-
The 39th International Symposium on Lattice Field Theory,
- Pub Date:
- April 2023
- DOI:
- 10.48550/arXiv.2210.11187
- arXiv:
- arXiv:2210.11187
- Bibcode:
- 2023slft.confE.225Z
- Keywords:
-
- High Energy Physics - Lattice;
- High Energy Physics - Phenomenology
- E-Print:
- 8 pages, 2 figures, Proceedings of the 39th International Symposium on Lattice Field Theory (LATTICE2022), 8th-13th August 2022, Bonn, Germany