| Summary: | I examine kinematic disturbance of star-forming gas in nearby galaxies, as part of the SAMI Galaxy Survey (SGS) on the Anglo-Australian telescope. Analysis of the frequency, causes, and nature of local galaxy disturbance will contribute to understanding galaxy evolution, one of the foremost areas of study in modern astronomy. I calculate the fraction of galaxies within the SGS sample that are disturbed. A method based on kinemetry is used to measure the asymmetry in the gas kine- matics for each galaxy. A kinematic asymmetry coefficient (vasym) is calculated, which clearly distinguishes between perturbed and normal galaxies. This is not the case for quantitative morphology coefficients G, M20, and A. Concentration of star formation and asymmetry are correlated, particularly for high stellar mass galaxies. There is an inverse link between vasym and stellar mass. Using data from the GAMA survey, it is found that the link between vasym and stellar mass is stronger than any trends in distance to first nearest neighbour (d1). For high mass galaxies, there is an inverse trend between d1 and vasym, not lower stellar mass galaxies. That is, for low mass galaxies, internal gas dynamics drive vasym. The Tully-Fisher relation (TFR) for our sample is shown. The TFR covers 7.5 < log(M∗/M8) < 11.0, with increased scatter at lower log(M∗/M8). There is a strong link between vasym and scatter below the TFR. Several causes of scatter are examined, and a slit placed on our velocity maps to compare with existing analysis. Misalignment between the kinematic and photometric position angles (PA) is linked to asymmetry and a significant cause of scatter, when the simulated slit is placed along the photometric PA. This demonstrates an important means of identifying the cause of and, where necessary, minimising scatter, in future TFR studies.
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