# KROSS-SAMI: A Direct IFS Comparison of the Tully-Fisher Relation Across 8 Gyr since z ~ 1

We construct Tully-Fisher relations (TFRs), from large samples of galaxies with spatially-resolved Hα emission maps from the K-band Multi-Object Spectrograph (KMOS) Redshift One Spectroscopic Survey (KROSS) at z ≈ 1. We compare these to data from the Sydney-Australian-Astronomical-Observatory Multi-object Integral- Field Spectrograph (SAMI) Galaxy Survey at z ≈ 0. We stringently match the data quality of the latter to the former, and apply identical analysis methods and sub-sample selection to both to conduct a direct comparison of the absolute K-band magnitude and stellar mass TFRs at z ≈ 1 and z ≈ 0. We find that the degraded data quality of the SAMI data matched to the quality of KROSS results in TFRs that differ significantly in slope, zero-point and (sometimes) scatter in comparison to the corresponding relations constructed from the original SAMI data. Further, these differences are, in every case, as large or larger than the differences between the KROSS z ≈ 1 and matched SAMI z ≈ 0 relations. We account for these differences, making a comparison of the TFR at z ≈ 1 and z ≈ 0 matched in both selection and data quality - the first of its kind. We find no change to the K-band TFR zero-point and only a small change of 0.15 ± 0.05 dex to the stellar mass TFR zero-point for strictly rotation-dominated (v2.2/σ > 3, where v2.2 is the intrinsic rotation velocity at 2.2 times the disk scale radius and σ is the intrinsic velocity dispersion), disk-like star-forming galaxies since z ≈ 1. This suggests the growth of stellar mass and dark matter in these galaxies may be intimately linked over the last ≈ 8 Gyr.

Publication Date:
January 2019
Paper PDF: