PIRSA:26050052

Video URL

https://pirsa.org/26050052

Probing Axion Clouds with EHT Data Using Closure Trace Analyses

Wang, Z. (2026). Probing Axion Clouds with EHT Data Using Closure Trace Analyses. Perimeter Institute for Theoretical Physics. https://pirsa.org/26050052

Wang, Zhiren. Probing Axion Clouds with EHT Data Using Closure Trace Analyses. Perimeter Institute for Theoretical Physics, May. 04, 2026, https://pirsa.org/26050052 

          @misc{ scivideos_PIRSA:26050052,
            doi = {10.48660/26050052},
            url = {https://pirsa.org/26050052},
            author = {Wang, Zhiren},
            keywords = {Other Physics},
            language = {en},
            title = {Probing Axion Clouds with EHT Data Using Closure Trace Analyses},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2026},
            month = {may},
            note = {PIRSA:26050052 see, \url{https://scivideos.org/pirsa/26050052}}
          }

Zhiren Wang Perimeter Institute for Theoretical Physics

Talk numberPIRSA:26050052
DOI10.48660/26050052
Source RepositoryPIRSA
Collection
Talk Type Scientific Series
Subject

Abstract

Axion-like particles can form clouds around rotating supermassive black holes through superradiant instability. Via axion-photon coupling, these clouds can imprint time-dependent oscillations on the observed electric vector position angle. I will present constraints on such clouds around M87* and Sgr A* using 2017 Event Horizon Telescope polarimetric data. The analysis is based on conjugate closure trace products, which are non-imaging and insensitive to dominant calibration systematics such as station gains and polarization leakage. I will highlight the contrast between the relatively stable M87* data and the highly variable Sgr A* case, and discuss the prospects of applying this pipeline to future EHT and more sensitive next-generation EHT observations.