Image of a regular phantom compact object and its luminosity under spherical accretions

TL;DR

This study analyzes the shadow and luminosity of a regular phantom compact object under spherical accretion, revealing how phantom hair influences observable features like shadow size and brightness.

Contribution

It introduces the effects of phantom hair on the shadow and luminosity of compact objects, including black holes and wormholes, under spherical accretion models.

Findings

Phantom hair increases shadow size and darkens the image.

Luminosity at the photon ring decreases with higher phantom parameter.

A jump in intensity occurs at the black hole-wormhole transition point.

Abstract

We have studied the shadow and its luminosity for a static and regular phantom compact object under the static spherical accretion and the infalling spherical accretion, respectively. Comparing with the usual Schwarzschild black hole, the presence of phantom hair yields the larger black hole shadow and the darker image. In both spherical accretion models, with the increase of phantom parameter, the maximum luminosity occurred at photon ring and the brightness of the central region in the shadow decrease, but in the region far from the shadow, the luminosity of image slightly increases. The image of a phantom wormhole and its luminosity have similar behaviors. Moreover, as the phantom charge parameter $\alpha$ increases up to the critical value at where the compact object changes from black hole to wormhole, there exists a jump for the specific intensity, which also appears in the slowly rotating case. This implies that the phantom hair is imprinted on both the shadow radius and the intensity of the electromagnetic flux radiation around compacted object.