Exploring ALPs beyond the canonical

Understand

Axion-like particles (ALPs) are interesting dark matter candidates both from the theoretical as well as from the experimental perspective.

• Usually they are motivated as pseudo-Nambu-Goldstone bosons.
• In this case one of their most important features is that their coupling to other particles is suppressed by a large scale, the vacuum expectation value of the field breaking the symmetry that gives rise to them.
• This naturally endows them with very weak interactions but also restricts the maximal field value and therefore the regions where sufficient dark matter is produced.