Speaker
Description
The Strongly Interacting Massive Particle (SIMP) paradigm has recently been increasingly studied. It provides dark matter candidates as pseudo-Goldstone bound states of dark fermions under a new gauge group. In this scenario freezeout occurs through $3\to 2$ dark matter self-annihilation and points to DM particles with masses of $\mathcal O(100 ~\text{MeV})$. We study the spectrum of the lightest mesons of $Sp(4)$ gauge theory with 2 massive almost-degenerate fundamental Dirac fermions using lattice gauge theory. This setup leads to a total of 5 pseudo-Goldstone bosons which can self-annihilate. In particular, we investigate the breaking of the flavour symmetry when making the fermions non-degenerate. We report that one pseudo-Goldstone is lighter than the others while the remaining heavier four pseudo-Goldstones are still mass-degenerate.
