Theory Seminar

Dark glueballs and their ultralight axions

by Gustavo Salinas (Northeastern Univ., Boston)

Europe/Berlin
313 (MPI Meeting rooms)

313

MPI Meeting rooms

Description
I discuss dark matter as a mixture of dark glueballs and their associated ultralight axions, a scenario well-motivated from a string theory perspective. Glueballs from a confining hidden gauge sector oversaturate the observed relic density for much of the natural UV parameter space. However, if the dark glueballs are only a fraction of the dark matter and the associated axion has a decay constant near the string scale, then this axion is ultralight and naturally realizes the fuzzy dark matter scenario with a modest tuning of a temperature ratio. The glueball self-interactions are much stronger than the typical self-interacting dark matter bounds. Astrophysical observations constrain the size of the glueball component relative to the axionic component, while electric dipole moments constrain mixing with the QCD axion.