PIRSA:22090085

Video URL

https://pirsa.org/22090085

Cusps of cusps: a universal model for extreme scattering events in the ISM

Jow, D. (2022). Cusps of cusps: a universal model for extreme scattering events in the ISM. Perimeter Institute for Theoretical Physics. https://pirsa.org/22090085

Jow, Dylan. Cusps of cusps: a universal model for extreme scattering events in the ISM. Perimeter Institute for Theoretical Physics, Sep. 20, 2022, https://pirsa.org/22090085 

          @misc{ scivideos_PIRSA:22090085,
            doi = {10.48660/22090085},
            url = {https://pirsa.org/22090085},
            author = {Jow, Dylan},
            keywords = {Cosmology},
            language = {en},
            title = {Cusps of cusps: a universal model for extreme scattering events in the ISM},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2022},
            month = {sep},
            note = {PIRSA:22090085 see, \url{https://scivideos.org/pirsa/22090085}}
          }

Dylan Jow Canadian Institute for Theoretical Astrophysics (CITA)

Talk numberPIRSA:22090085
DOI10.48660/22090085
Source RepositoryPIRSA
Collection
Talk Type Scientific Series
Subject

Abstract

Since the 80s, radio sources have been observed to undergo extreme scattering events (ESEs): large, frequency dependent flux modulations due to scattering off the ISM. Recently, the study of these events has undergone a revived interest due to the increase in pulsar timing data, as well as the realization that FRBs will be scattered by the same structures in the ISM. Models of the structures responsible for ESEs range from spherical-cow approximations (e.g. simple Gaussian profiles) to more exotic models (e.g. plasma shells around compact dark matter). Here we present a new model in which ESEs are produced by corrugated sheets in the ISM, which, when projected onto the plane of the sky, generically form A3 cusp catastrophes. We will argue that this model naturally explains several features in scattering data, including observations of PSR 0834+06 and the original Fiedler et al. 0954+658 ESE.  Moreover, this model is consistent with models of pulsar scintillation and does not require exotic physics to explain. We will discuss potential applications to FRB cosmology that arise from the universality of this model.

Zoom link:  https://pitp.zoom.us/j/94260081028?pwd=Vm8zVUd5ak1saWJYZFZ3MWF0L3g2dz09