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Recently a number of studies have found a similarity between the passive fraction of central and satellite galaxies when controlled for both stellar and halo mass. These results suggest that the quenching processes that affect galaxies are largely agnostic to central/satellite status, which contradicts the traditional picture of increased satellite quenching via environmental processes such as stripping, strangulation and starvation. Here we explore this further using the Galaxy And Mass Assembly (GAMA) survey which extends to ~2dex lower in stellar mass than SDSS, is more complete for closely-separated galaxies (>95% compared to >70%), and identifies lower-halo-mass groups outside of the very local Universe (M$_{mathrm{halo}}sim10^{12}$M$_{odot}$ at $0.1<z<0.2$). As far as possible we aim to replicate the selections, completeness corrections and central/satellite division of one of the previous studies but find clear differences between passive fractions of centrals and satellites. We also find that our passive fractions increase with both halo-to-satellite mass ratio and central-to-second rank mass ratio. This suggests that quenching is more efficient in satellites that are low-mass for their halo ($i.e$ at high halo-to-satellite mass ratio in comparison to low halo-to-satellite mass ratio) and are more likely to be passive in older groups - forming a consistent picture of environmental quenching of satellites. We then discuss potential explanations for the previously observed similarity, such as dependence on the group-finding method.
We explore the clustering of galaxy groups in the Galaxy and Mass Assembly (GAMA) survey to investigate the dependence of group bias and profile on separation scale and group mass. Due to the inherent uncertainty in estimating the group selection fun
How do galaxy properties (such as stellar mass, luminosity, star formation rate, and morphology) and their evolution depend on the mass of their host dark matter halo? Using the Galaxy and Mass Assembly (GAMA) group catalogue, we address this questio
We explore the radial distribution of star formation in galaxies in the SAMI Galaxy Survey as a function of their local group environment. Using a sample of galaxies in groups (with halo masses less than $ simeq 10^{14} , mathrm{M_{odot}}$) from the
We measure the projected 2-point correlation function of galaxies in the 180 deg$^2$ equatorial regions of the GAMA II survey, for four different redshift slices between z = 0.0 and z=0.5. To do this we further develop the Cole (2011) method of produ
The Galaxy And Mass Assembly Survey (GAMA) covers five fields with highly complete spectroscopic coverage ($>95$ per cent) to intermediate depths ($r<19.8$ or $i < 19.0$ mag), and collectively spans 250 square degrees of Equatorial or Southern sky. F