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arXiv · 2605.24102

Red/Blue shifts of photons in a Hayward black hole immersed in perfect fluid dark matter

L. Marlene. López·L. A. López
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Abstract

We investigate the red/blue shifts of photons emitted by particles moving along stable circular orbits around a Hayward black hole immersed in perfect fluid dark matter (PFDM). The PFDM contribution modifies the horizon structure and shifts the characteristic radii associated with circular motion, including the photon sphere and the ISCO radius. The corresponding redshift and blueshift are found to be sensitive to both the magnitude and sign of the PFDM parameter, providing potentially observable signatures of the surrounding dark matter distribution. Finally, we analyze the black hole shadow and compare its size with the observational constraints from Sgr A*. Positive values of the PFDM parameter reduce the shadow radius, whereas negative values produce larger deviations from the Schwarzschild case, suggesting that shadow observations may constrain the PFDM contribution.

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L. Marlene. López, L. A. López. 2026-05-22. Red/Blue shifts of photons in a Hayward black hole immersed in perfect fluid dark matter. https://arxiv.org/abs/2605.24102

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