The centers of our Galaxy and the nearby Messier 87 are known to contain supermassive black holes, which support accretion flows that radiate across the electromagnetic spectrum. Although the composition of the accreting gas is unknown, it is likely a mix of ionized hydrogen and helium. We use a simple analytic model and a suite of numerical general relativistic magnetohydrodynamic accretion simulations to study how polarimetric images and spectral energy distributions of the source are influenced by the hydrogen/helium content of the accreting matter. We aim to identify general trends rather than make quantitatively precise predictions, since it is not possible to fully explore the parameter space of accretion models. If the ion-to-electron temperature ratio is fixed, then increasing the helium fraction increases the gas temperature; to match the observational flux density constraints, the number density of electrons and magnetic field strengths must therefore decrease. In our numerical simulations, emission shifts from regions of low to high plasma
This content will become publicly available on February 1, 2024
- Award ID(s):
- 1816420
- NSF-PAR ID:
- 10406755
- Date Published:
- Journal Name:
- Galaxies
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2075-4434
- Page Range / eLocation ID:
- 11
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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