https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 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:34329 ⋆) ≤ 11 M_⊙ in projected densities 0 ≤ Σ₅ < 3 galaxies Mpc⁻², all Hɪ fractions of galaxies near filaments are statistically indistinguishable from the control sample. Galaxies with stellar masses log(M_⋆) ≥ 11 M_⊙ have a systematically higher Hɪ fraction near filaments than the control sample. The greatest difference is 0.75 dex, which is 5.5θ difference at mean projected densities of 1.45 galaxies Mpc⁻². We suggest that this is evidence for massive galaxies accreting cold gas from the intrafilament medium that can replenish some Hɪ gas. This supports cold mode accretion where filament galaxies with a large gravitational potential can draw gas from the large-scale structure.]]> Wed 04 Sep 2019 09:39:57 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:38595 L_{[C II]}/L_FIR, varies by a factor of at least 140 among these four clumps. In particular, for AGAL313.576+0.324, no [C II] line emission is detected despite a FIR luminosity of 24,000 L. AGAL313.576+0.324 lies a factor of more than 100 below the empirical correlation curve between L_{[C II]}/L_FIR and S_v (63 μm) S_v (158 μm) found for galaxies. AGAL313.576+0.324 may be in an early evolutionary “protostellar” phase with insufficient ultraviolet flux to ionize carbon, or in a deeply embedded “‘hypercompact” H II region phase where dust attenuation of UV flux limits the region of ionized carbon to undetectably small volumes. Alternatively, its apparent lack of [C II] emission may arise from deep absorption of the [C II] line against the 158 μm continuum, or self-absorption of brighter line emission by foreground material, which might cancel or diminish any emission within the FIFI-LS instrument’s broad spectral resolution element (AV ~ 250 km s⁻¹).]]> Tue 16 Nov 2021 15:25:30 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45558 Tue 01 Nov 2022 12:41:10 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42725 Thu 01 Sep 2022 13:18:22 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47472 Mon 23 Jan 2023 11:12:30 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:32088 Galaxy Evolution Explorer near-ultraviolet (NUV) galaxy photometry with the Sloan Digital Sky Survey group catalogue of Yang et al. We compared the (NUV − r) colours of grouped and non-grouped galaxies, and find a significant increase in the fraction of red sequence galaxies with blue (NUV − r) colours outside of groups. When comparing galaxies in mass-matched samples of satellite (non-central), and non-grouped galaxies, we found a >4σ difference in the distribution of (NUV − r) colours, and an (NUV − r) blue fraction >3σ higher outside groups. A comparison of satellite and non-grouped samples has found the NUV fraction is a factor of ∼2 lower for satellite galaxies between 10^10.5 and 10^10.7,M _⊙, showing that higher mass galaxies are more likely to have residual star formation when not influenced by a group potential. There was a higher (NUV − r) blue fraction of galaxies with lower Sérsic indices (n < 3) outside of groups, not seen in the satellite sample. We have used stellar population models of Bruzual & Charlot with multiple burst, or exponentially declining star formation histories to find that many of the (NUV − r) blue non-grouped galaxies can be explained by a slow (∼2 Gyr) decay of star formation, compared to the satellite galaxies. We suggest that taken together, the difference in (NUV − r) colours between samples can be explained by a population of secularly evolving, non-grouped galaxies, where star formation declines slowly. This slow channel is less prevalent in group environments where more rapid quenching can occur.]]> Fri 27 Apr 2018 15:08:51 AEST ]]>