The Spitzer-HETDEX Exploratory Large Area Survey. IV. Model-Based Multi-wavelength Photometric Catalog

TL;DR

This paper introduces a comprehensive 16-band photometric catalog for the SHELA survey, combining new imaging and model-based extraction methods to improve source detection and photometry over a large area, facilitating advanced extragalactic research.

Contribution

It presents a new model-based multi-wavelength photometric catalog with enhanced depth and accuracy, validated against existing surveys, covering 27 square degrees with four million sources.

Findings

The catalog reaches 80% completeness at AB mag 24.7 in riz bands.

Photometric redshifts have a 1σ scatter of 0.04 up to z=1.

Model-based photometry captures more flux from resolved sources.

Abstract

We present a 0.3--4.5 $\mu$m 16-band photometric catalog for the Spitzer/HETDEX Exploratory Large-Area (SHELA) survey. SHELA covers a $\sim 27$ deg$^2$ field within the footprint of the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). Here we present new DECam imaging and a $rizK_s$-band-selected catalog of four million sources extracted using a fully model-based approach. We validate our photometry by comparing with the model-based DECam Legacy Survey. We analyze the differences between model-based and aperture photometry by comparing with the previous SHELA catalog, finding that our model-based photometry can measure point sources to fainter fluxes and better capture the full emission of resolved sources. The catalog is $80\%$ ($50\%$) complete at $riz \sim 24.7$ ($25.1$) AB mag, and the optical photometry reaches a $5\sigma$ depth of $\sim 25.5$ AB mag. We measure photometric redshifts and achieve $1\sigma$ scatter of $\Delta z/(1+z)$ of 0.04 with available spectroscopic redshifts at $0 \le z \le 1$. This large area, multi-wavelength photometric catalog, combined with spectroscopic information from HETDEX, will enable a wide range of extragalactic science investigations.