1. Relative depolarization of the black hole photon ring in GRMHD models of Sgr A* and M87.
- Author
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Jiménez-Rosales, A, Dexter, J, Ressler, S M, Tchekhovskoy, A, Bauböck, M, Dallilar, Y, de Zeeuw, P T, Drescher, A, Eisenhauer, F, von Fellenberg, S, Gao, F, Genzel, R, Gillessen, S, Habibi, M, Ott, T, Stadler, J, Straub, O, and Widmann, F
- Subjects
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BLACK holes , *PHOTONS , *GENERAL relativity (Physics) , *LINEAR polarization , *MAGNETIC traps - Abstract
Using general relativistic magnetohydrodynamic simulations of accreting black holes, we show that a suitable subtraction of the linear polarization per pixel from total intensity images can enhance the photon ring feature. We find that the photon ring is typically a factor of ≃2 less polarized than the rest of the image. This is due to a combination of plasma and general relativistic effects, as well as magnetic turbulence. When there are no other persistently depolarized image features, adding the subtracted residuals over time results in a sharp image of the photon ring. We show that the method works well for sample, viable GRMHD models of Sgr A* and M87*, where measurements of the photon ring properties would provide new measurements of black hole mass and spin, and potentially allow for tests of the 'no-hair' theorem of general relativity. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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