We investigate the Tully-Fisher Relation ( TFR ) for a morphologically and kinematically diverse sample of galaxies from the SAMI Galaxy Survey using 2 dimensional spatially resolved H \alpha velocity maps and find a well defined relation across the stellar mass range of 8.0 < \log ( M _ { * } / M _ { \odot } ) < 11.5 .

We use an adaptation of kinemetry to parametrise the kinematic H \alpha asymmetry of all galaxies in the sample , and find a correlation between scatter ( i.e .
residuals off the TFR ) and asymmetry .
This effect is pronounced at low stellar mass , corresponding to the inverse relationship between stellar mass and kinematic asymmetry found in previous work .
For galaxies with \log ( M _ { * } / M _ { \odot } ) < 9.5 , 25 \pm 3 \% are scattered below the root mean square ( RMS ) of the TFR , whereas for galaxies with \log ( M _ { * } / M _ { \odot } ) > 9.5 the fraction is 10 \pm 1 \%

We use ‘ simulated slits ’ to directly compare our results with those from long slit spectroscopy and find that aligning slits with the photometric , rather than the kinematic , position angle , increases global scatter below the TFR .
Further , kinematic asymmetry is correlated with misalignment between the photometric and kinematic position angles .
This work demonstrates the value of 2D spatially resolved kinematics for accurate TFR studies ; integral field spectroscopy reduces the underestimation of rotation velocity that can occur from slit positioning off the kinematic axis .