Dark matter effect on the weak deflection angle by black holes at the center of Milky Way and M87 galaxies

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In this paper, we investigated the effect of dark matter on the weak deflection angle by black holes at the galactic center.

• We consider three known dark matter density profiles such as the Cold Dark Matter (CDM), Scalar Field Dark Matter (SFDM), and the Universal Rotation Curve (URC) from the Burkert profile.
• To achieve this goal, we used how the positional angles are measured by Ishihara et al.
• method based on Gauss-Bonnet theorem (GBT) on the optical metric.