Strong gravitational lensing for the charged black holes with scalar hair

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The strong gravitational lensing for charged black holes with scalar hair in Einstein-Maxwell-Dilaton theory are studied.

• We find, with the increase of scalar hair, that the radius of the photon sphere, minimum impact parameter, angular image position and relative magnitude increase, while the deflection angle and angular image separation decrease.
• Our results can be reduced to those of the Schwarzschild black hole in two cases, one of them is that the scalar hair disappears, the other is that the coupling constants take particular values with arbitrary scalar hair.