We present the photometric redshift characterization and calibration for the Dark Energy Camera All Data Everywhere (DECADE) weak lensing dataset: a catalog of 107 million galaxies observed by the Dark Energy Camera (DECam) in the northern Galactic cap. The redshifts are estimated from a combination of wide-field photometry, deep-field photometry with associated redshift estimates, and a transfer function between the wide field and deep field that is estimated using a source injection catalog. We construct four tomographic bins for the galaxy catalog, and estimate the redshift distribution, n(z), within each one using the Self-organizing Map Photo-Z (SOMPZ) methodology. Our estimates include the contributions from sample variance, zeropoint calibration uncertainties, and redshift biases, as quantified for the deep-field dataset. The total uncertainties on the mean redshifts are σ⟨z⟩≈0.01. The SOMPZ estimates are then compared to those from the clustering redshift method, obtained by cross-correlating our source galaxies with galaxies in spectroscopic surveys, and are shown to be consistent with each other.
@article{arxiv.2502.17675,
title = {The DECADE cosmic shear project II: photometric redshift calibration of the source galaxy sample},
author = {D. Anbajagane and A. Alarcon and R. Teixeira and C. Chang and L. F. Secco and C. Y. Tan and A. Drlica-Wagner and M. Adamow and R. A. Gruendl and G. Giannini and M. R. Becker and P. S. Ferguson and N. Chicoine and Z. Zhang and K. Herron and D. Suson and A. N. Alsina and A. Amon and C. R. Bom and J. A. Carballo-Bello and W. Cerny and A. Choi and Y. Choi and C. Doux and K. Eckert and M. Gatti and D. Gruen and W. G. Hartley and K. Herner and E. M. Huff and D. J. James and N. Kuropatkin and C. E. Martínez-Vázquez and P. Massana and S. Mau and J. McCullough and G. E. Medina and B. Mutlu-Pakdil and J. Myles and M. Navabi and N. E. D. Noël and A. B. Pace and M. Raveri and A. H. Riley and J. D. Sakowska and D. Sanchez-Cid and D. J. Sand and L. Santana-Silva and I. Sevilla-Noarbe and M. Soares-Santos and G. S. Stringfellow and A. K. Vivas and M. Yamamoto},
journal= {arXiv preprint arXiv:2502.17675},
year = {2025}
}