Low Resolution Spectral Templates For Galaxies From 0.2 -- 10 microns

TL;DR

This paper presents a set of optimized low resolution spectral templates for galaxies across 0.2 to 10 microns, enabling improved photometric redshift estimation and galaxy property analysis.

Contribution

It introduces a novel method to derive galaxy spectral templates from multi-band photometry and develops algorithms for accurate photometric redshifts, K corrections, and luminosity calculations.

Findings

Photometric redshifts achieve an accuracy of σ_z/(1+z)=0.04 for 95% of the sample.

Spectral templates reveal a bimodal 5-8μm color distribution in galaxies.

Templates facilitate studies of galaxy spectral types and luminosity functions across redshifts.

Abstract

We built an optimal basis of low resolution templates for galaxies over the wavelength range from 0.2 to 10 $\mu$m using a variant of the algorithm presented by Budavari et al. (2000). We derived them using eleven bands of photometry from the NDWFS, FLAMEX, zBo\"otes and IRAC Shallow surveys for 16033 galaxies in the NDWFS Bo\"otes field with spectroscopic redshifts measured by the AGN and Galaxy Evolution Survey. We also developed algorithms to accurately determine photometric redshifts, K corrections and bolometric luminosities using these templates. Our photometric redshifts have an accuracy of $\sigma_z/(1+z) = 0.04$ when clipped to the best 95%. We used these templates to study the spectral type distribution in the field and to estimate luminosity functions of galaxies as a function of redshift and spectral type. In particular, we note that the 5-8$\mu$m color distribution of galaxies is bimodal, much like the optical g--r colors.