Photometric Redshifts based on standard SED fitting procedures

TL;DR

This paper evaluates the accuracy of photometric redshifts obtained via standard SED fitting, introduces a public code, and analyzes how observational and theoretical factors influence redshift estimation.

Contribution

It presents a detailed study of photometric redshift accuracy using SED fitting, along with a publicly available code and analysis of various observational and model assumptions.

Findings

Photometric redshift accuracy varies with filter set and photometric precision.

The fraction of catastrophic errors depends on redshift and data quality.

The study provides expected error rates for real observational data.

Abstract

In this paper we study the accuracy of photometric redshifts computed through a standard SED fitting procedure, where SEDs are obtained from broad-band photometry. We present our public code hyperz, which is presently available on the web. We introduce the method and we discuss the expected influence of the different observational conditions and theoretical assumptions. In particular, the set of templates used in the minimization procedure (age, metallicity, reddening, absorption in the Lyman forest, ...) is studied in detail, through both real and simulated data. The expected accuracy of photometric redshifts, as well as the fraction of catastrophic identifications and wrong detections, is given as a function of the redshift range, the set of filters considered, and the photometric accuracy. Special attention is paid to the results expected from real data.