ORIGINS Guest Sam Witte: Producing Axions in the Polar Caps of Neutron Stars

Cluster Basement Seminar Room, Building R1 on IPP Campus

Cluster Basement Seminar Room, Building R1 on IPP Campus

Boltzmannstr. 2, 85748 Garching

Dr. Sam Witte (GRAPPA, University of Amsterdam) is a long-term guest of Georg Raffelt (MPP) whose current research focuses on the astrophysical probes of axions.

In this talk I will discuss a novel idea for the production and subsequent detection of axions produced in the polar caps of neutron stars. The production of these particles is driven by the non-linear dynamics of the plasma in localized regions of the neutron star magnetosphere, and can lead to the generation of more than 10^50 axions / second, with characteristic energies spanning O(MHz) to O(100 GHz). The sourced axions can be divided into two populations: (i) a relativistic population that streams out of the magnetosphere, and (ii) a semi-relativistic population that contributes to a growing bound state cloud of axions. Depending on the properties of the neutron star magnetosphere, either one or both of these populations can lead to powerful electromagnetic signatures in the radio band. I will show that existing radio data of nearby pulsars can already be used to constrain axions with masses below ~10^-6 eV.  

Excellence Cluster ORIGINS
Boltzmannstr. 2 / Building R1 on IPP Campus
Basement Seminar Room (Hybrid event)
Meeting ID: 620 9129 6955
Passcode: 762629

Please arrive a bit early and grab a coffee and some cookies in our Cluster kitchen on the ground floor before or after the talk.

Organized by

Excellence Cluster ORIGINS
Dr. Alice M. Smith-Gicklhorn
Scientific Manager