Physical Weighting of Galaxy-Scale Synthetic Spectra

Determine whether an exponential stellar-light weighting profile or a weighting scheme restricted to sightlines back-lit by young star-cluster regions provides the more accurate representation of the background light distribution when constructing galaxy-scale synthetic down-the-barrel spectra.

Background

To combine pencil-beam Trident spectra into a galaxy-wide down-the-barrel spectrum, the paper applies a spatial weighting intended to represent the nonuniform stellar continuum. The fiducial model uses an exponential radial profile, while an alternative selects cells associated with hot star-cluster regions. The authors compare these prescriptions but do not establish which most faithfully represents the light distribution relevant to realistic simulated observations.

References

By masking for only star-forming regions in our simulation data, we can test to what extent this effect manifests in the synthetic spectra, as it is not entirely clear whether a simple exponential light profile or a light background dominated by young star clusters is the better approximation for simulated data.

— Studying Outflows with Synthetic Absorption Line Spectra from High Resolution Simulations  (2609.10868 - Magee et al., 9 Sep 2026) in Section 3.1.1, Weighting Function