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arXiv · 2307.01529

Shadows and photon rings of a spherically accreting Kehagias-Sfetsos black hole

Mohaddese Heydari-Fard·Malihe Heydari-Fard·Nematollah Riazi
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Abstract

By considering Kehagias-Sfetsos black hole in the framework of the Ho\v{r}ava-Lifshitz gravity, we study the optical appearance of such black holes surrounded by spherical accretion flow. For the static/infalling spherical accretion flow, we compute the observed specific intensity as a function of impact parameter. We also investigate the effect of the Ho\v{r}ava parameter and accreting matter on the luminosity of shadows and photon rings. It is found that an increase in the Ho\v{r}ava parameter decreases the shadow size, while the shadows and photon rings luminosities increase. Moreover, we constrain the Ho\v{r}ava parameter from the observational data reported by the Event Horizon Telescope for M87* and Sgr A*.

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Mohaddese Heydari-Fard, Malihe Heydari-Fard, Nematollah Riazi. 2023-07-04. Shadows and photon rings of a spherically accreting Kehagias-Sfetsos black hole. https://doi.org/10.1142/s0218271823500888

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