Thick accretion disk configurations around a compact object in the brane-world scenario

TL;DR

This study analyzes how the PPN parameter influences the structure and size of thick accretion disks around a brane-world compact object, revealing that larger PPN parameters lead to smaller disks but larger Roche lobes, affecting disk stability.

Contribution

It provides a detailed analysis of equipotential surfaces and disk configurations around a brane-world compact object, highlighting the impact of the PPN parameter on disk morphology and stability.

Findings

Increased PPN parameter decreases disk size

Larger PPN parameter enlarges Roche lobe regions

Pressure gradient in the disk decreases with PPN parameter

Abstract

We have studied equipotential surfaces of a thick accretion disk around a Casadio-Fabbri-Mazzacurati (CFM) compact object in the brane-world scenario, which owns a mass parameter together with a parameterized post-newtonian (PPN) parameter. With the increase of the PPN parameter, the size of the thick accretion disk decreases, but the corresponding Roche lobe size increases. Thus, the larger PPN parameter yields the larger region of existing bound disk structures where the fluid is not accreted into the central wormhole. Moreover, with the increase of the PPN parameter, the position of the Roche lobe gradually moves away from the central compact object, the thickness of the region enclosed by the Roche lobe decreases near the compact object, but increases in the region far from the compact object. Our results also show that the pressure gradient in the disk decreases with the PPN parameter. These effects of the PPN parameter on thick accretion disk could help to further understand compact objects in brane-world scenario.