Sam Witte, GRAPPA Institute, University of Amsterdam
Aula 507, Pere Pascual
Abstract: Axions constitute excellent dark matter candidates, can resolve one of the major outstanding problems in particle physics (the Strong CP problem), and appear ubiquitously in well-motivated high energy theories — as such, these particles represent one of the best candidates for physics beyond the Standard Model. In this talk I will discuss novel avenues to probe axion physics by looking at the behaviour of these particles in the magnetospheres of neutron star; I will focus in particular on three distinct signatures, including: (1) looking for narrow radio spectral lines arising from the resonant transition of axion dark matter, (2) looking for broadband radio emission generated from relativistic axions sourced in the polar caps of neutron stars, and (3) looking for radio bursts arising from dense clouds of axions around neutron stars. I will highlight recent efforts on the observational front, showing that these processes have led to leading limits on axions across a broad range of parameter space.