Dust effects on the derived Sersic indexes of disks and bulges in spiral galaxies

TL;DR

This study quantifies how dust affects the measurement of Sersic indexes in spiral galaxy disks and bulges, showing that dust generally lowers the observed index, especially in optically thick regions.

Contribution

It provides a theoretical analysis using radiative transfer simulations to understand dust's impact on Sersic index measurements in spiral galaxies.

Findings

Dust lowers measured Sersic indexes in most cases.

Effects are stronger for disks and bulges viewed through optically thick lines of sight.

Simulations used radiative transfer models to quantify these effects.

Abstract

We present a theoretical study that quantifies the effect of dust on the derived Sersic indexes of disks and bulges. The changes in the derived parameters from their intrinsic values (as seen in the absence of dust) were obtained by fitting Sersic distributions on simulated images of disks and bulges produced using radiative transfer calculations and the model of Popescu et al. 2011. We found that dust has the effect of lowering the measured Sersic index in most cases, with stronger effects for disks and bulges seen through more optically thick lines of sight.