Using a sample of 67 galaxies from the MIGHTEE Survey Early Science data we study the HI-based baryonic Tully-Fisher relation (bTFr), covering a period of ∼one billion years (0≤z≤0.081). We consider the bTFr based on two different rotational velocity measures: the width of the global HI profile and Vout, measured as the outermost rotational velocity from the resolved HI rotation curves. Both relations exhibit very low intrinsic scatter orthogonal to the best-fit relation (σ⊥=0.07±0.01), comparable to the SPARC sample at z≃0. The slopes of the relations are similar and consistent with the z≃0 studies (3.66+0.35−0.29 for W50 and 3.47+0.37−0.30 for Vout). We find no evidence that the bTFr has evolved over the last billion years, and all galaxies in our sample are consistent with the same relation independent of redshift and the rotational velocity measure. Our results set up a reference for all future studies of the HI-based bTFr as a function of redshift that will be conducted with the ongoing deep SKA pathfinders surveys.
MIGHTEE-HI: The baryonic Tully-Fisher relation over the last billion years, Anastasia A. Ponomareva (Oxford), Wanga Mulaudzi, Natasha Maddox, Bradley S. Frank, Matt J. Jarvis, Enrico M. Di Teodoro, Marcin Glowacki, Renée C. Kraan-Korteweg, Tom A. Oosterloo, Elizabeth A. K. Adams, Hengxing Pan, Isabella Prandoni, Sambatriniaina H. A. Rajohnson, Francesco Sinigaglia, Nathan J. Adams, Ian Heywood, Rebecca A. A. Bowler, Peter W. Hatfield, Jordan D. Collier, Srikrishna Sekhar, accepted for publication in MNRAS, arXiv:2109.04992