Saved in:
Bibliographic Details
Main Authors: McDonough, Bryanne, Curtis, Olivia, Brainerd, Tereasa
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2503.15702
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916801986691072
author McDonough, Bryanne
Curtis, Olivia
Brainerd, Tereasa
author_facet McDonough, Bryanne
Curtis, Olivia
Brainerd, Tereasa
contents Scaling relationships, both integrated and spatially resolved, arise due to the physical processes that govern galaxy evolution and are frequently measured in both observed and simulated data. However, the accuracy and comparability of these measurements are hindered by various differences between studies such as spatial resolution, sample selection criteria, and fitting technique. Here, we compare variations of standard least squares techniques to the ridge line method for identifying spatially resolved scaling relations ($Σ_*-Σ_{\rm SFR}$, $Σ_*-Σ_{\rm gas}$, and $Σ_{\rm gas}-Σ_{\rm SFR}$) for TNG100 galaxies. We find that using the ridge line technique to fit these scaling relations with a double linear function results in significantly better fits than fitting with ordinary least squares. We further illustrate the utility of the ridge line technique with an investigation into the dependence of rSFMS measurements on spatial resolution and smoothing scale. Specifically, we find that the slope of the rSFMS at low-$Σ_*$ is independent (within $2σ$) of spatial resolution and smoothing scale. Finally, we discuss the need for a consistent re-analysis of resolved scaling relations in the literature and physically motivate adoption of the ridge line technique over other fitting methods.
format Preprint
id arxiv_https___arxiv_org_abs_2503_15702
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Measuring Scaling Relationships: Fitting Technique Matters
McDonough, Bryanne
Curtis, Olivia
Brainerd, Tereasa
Astrophysics of Galaxies
Scaling relationships, both integrated and spatially resolved, arise due to the physical processes that govern galaxy evolution and are frequently measured in both observed and simulated data. However, the accuracy and comparability of these measurements are hindered by various differences between studies such as spatial resolution, sample selection criteria, and fitting technique. Here, we compare variations of standard least squares techniques to the ridge line method for identifying spatially resolved scaling relations ($Σ_*-Σ_{\rm SFR}$, $Σ_*-Σ_{\rm gas}$, and $Σ_{\rm gas}-Σ_{\rm SFR}$) for TNG100 galaxies. We find that using the ridge line technique to fit these scaling relations with a double linear function results in significantly better fits than fitting with ordinary least squares. We further illustrate the utility of the ridge line technique with an investigation into the dependence of rSFMS measurements on spatial resolution and smoothing scale. Specifically, we find that the slope of the rSFMS at low-$Σ_*$ is independent (within $2σ$) of spatial resolution and smoothing scale. Finally, we discuss the need for a consistent re-analysis of resolved scaling relations in the literature and physically motivate adoption of the ridge line technique over other fitting methods.
title Measuring Scaling Relationships: Fitting Technique Matters
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2503.15702