PHYSICS DISSERTATION DEFENSE: David Cyncynates

Ph.D. Candidate:  David Cyncynates

Research Advisor: Savas Dimopoulos

Date: April 20
Time: 2:30 PM

Location: PAB 102/103

Zoom Link:  https://stanford.zoom.us/j/6573893184

Zoom Password: email nickswan [at] stanford.edu (nickswan[at]stanford[dot]edu) for password

 

Title: Friendship in the Axiverse

Abstract: The Axiverse is a scenario in which axion-like particles are distributed over many orders of magnitude in mass and interact with one another through a joint potential. In this talk, I will show how non-linearities in this potential lead to a new type of resonant energy transfer between "friendly" axions with nearby masses. This resonance generically transfers energy from axions with larger decay constants to those with smaller decay constants, leading to a multitude of signatures. These include enhanced direct detection prospects for a resonant pair comprising even a small subcomponent of dark matter, and boosted small-scale structure if the pair is the majority of DM. Near-future iterations of experiments such as ADMX and DM Radio will be sensitive to this scenario, as will astrophysical probes of DM substructure.