Visible light exposure of galaxy cluster Abell 2744 from NASA/ESA Hubble Space Telescope and ESO's Very Large Telescope, X-ray data from NASA's Chandra X-ray Observatory & math reconstruction of dark matter location. D. Coe & J. Merten/ESO/NASA/ESA/CXC
Theory Seminar

Physics Theory Seminar with Samuel Witte on Neutron Stars

Samuel Witte (Hosted by Ferrer) from GRAPPA, University of Amsterdam will be presenting the seminar "Neutron Stars as Axion Laboratories"

The QCD axion and axion-like particles are among the most well-motivated and sought after physics beyond the Standard Model — this is a consequence of the fact that they appear copiously in high energy theories and can resolve major outstanding problems in modern physics (including the strong CP problem and dark matter). In this talk I will show that the magnetospheres of neutron stars, hosting large magnetic fields and a dilute inhomogeneous plasma, offer incredibly powerful probes of axion physics. I will focus in particular on novel theoretical developments and search strategies targeting: (i) resonant photon production from axion dark matter, and (ii) the production of axions due to the collapse of vacuum gaps in the polar caps of active neutron stars. These are promising and highly complementary searches which offer significant promise of testing a broad range of the most well-motivated axion parameter space.

Zoom link available upon request at physics@wustl.edu.
Post-docs and students' Q&A with the speaker starts at 2:15 pm. Contact Garrett King for the Q&A Zoom link.