The problem of dust attenuation in photometric decomposition of edge-on galaxies and possible solutions

TL;DR

This study investigates how dust affects the accuracy of photometric decomposition in edge-on galaxies, demonstrating that dust causes significant errors and proposing methods to mitigate these effects for more reliable structural parameter retrieval.

Contribution

The paper introduces radiative transfer simulations of edge-on galaxies and evaluates techniques like masking and analytical dust models to improve decomposition accuracy.

Findings

Dust causes significant systematic errors in structural parameters.

Even low dust content leads to notable offsets in measurements.

Analytical models and masking improve decomposition reliability.

Abstract

The presence of dust in spiral galaxies affects the ability of photometric decompositions to retrieve the parameters of their main structural components. For galaxies in an edge-on orientation, the optical depth integrated over the line-of-sight is significantly higher than for those with intermediate or face-on inclinations, so it is only natural to expect that for edge-on galaxies, dust attenuation should severely influence measured structural parameters. In this paper, we use radiative transfer simulations to generate a set of synthetic images of edge-on galaxies which are then analysed via decomposition. Our results demonstrate that for edge-on galaxies, the observed systematic errors of the fit parameters are significantly higher than for moderately inclined galaxies. Even for models with a relatively low dust content, all structural parameters suffer offsets that are far from negligible. In our search for ways to reduce the impact of dust on retrieved structural parameters, we test several approaches, including various masking methods and an analytical model that incorporates dust absorption. We show that using such techniques greatly improves the reliability of decompositions for edge-on galaxies.