https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34514 Rₑ) and ellipticity (ϵₑ) are used to separate fast and slow rotators; there exists a good correspondence to regular and non-regular rotators, respectively, as also seen in earlier studies. We confirm that regular rotators show a strong h₃ versus V/σ anti-correlation, whereas quasi-regular and non-regular rotators show a more vertical relation in h₃ and V/σ. Motivated by recent cosmological simulations, we develop an alternative approach to kinematically classify galaxies from their individual h₃ versus V/σ signatures. Within the SAMI Galaxy Survey, we identify five classes of high-order stellar kinematic signatures using Gaussian mixture models. Class 1 corresponds to slow rotators, whereas Classes 2-5 correspond to fast rotators. We find that galaxies with similar λ_Rₑ - ϵₑ values can show distinctly different h₃ - V/σ signatures. Class 5 objects are previously unidentified fast rotators that show a weak h₃ versus V/σ anti-correlation. From simulations, these objects are predicted to be disk-less galaxies formed by gas-poor mergers. From morphological examination, however, there is evidence for large stellar disks. Instead, Class 5 objects are more likely disturbed galaxies, have counter-rotating bulges, or bars in edge-on galaxies. Finally, we interpret the strong anti-correlation in h₃ versus V/σ as evidence for disks in most fast rotators, suggesting a dearth of gas-poor mergers among fast rotators.]]> Wed 20 Mar 2019 13:17:45 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34022 −1 without the need to smooth or grid the data. Our fitting methods are validated using a set of simulated 2MTF surveys. Using these simulations we also identify that the Gaussian distributed estimator for peculiar velocities of Watkins & Feldman is suitable for measuring the velocity power spectrum, but sub-optimal for the 2MTF data compared to using magnitude fluctuations δm, and that, whilst our fits are robust to a change in fiducial cosmology, future peculiar velocity surveys with more constraining power may have to marginalize over this. We obtain scale-dependent constraints on the growth rate of structure in two bins, finding fσ₈ = [0.55^+0.16_−0.13,0.40^+0.16_−0.17] in the ranges k = [0.007–0.055, 0.55–0.150] h Mpc⁻¹. We also find consistent results using four bins. Assuming scale-independence we find a value fσ₈ = 0.51^+0.09_−0.08⁠, a ∼16 per cent measurement of the growth rate. Performing a consistency check of general relativity (GR) and combining our results with cosmic microwave background data only we find γ = 0.45^+0.10_−0.11⁠, a remarkable constraint considering the small number of galaxies. All of our results are completely independent of the effects of galaxy bias, and fully consistent with the predictions of GR (scale-independent fσ₈ and γ ≈ 0.55).]]> Tue 03 Sep 2019 18:22:23 AEST ]]>