Citation for published item:fryntD tFtF nd ywersD wFF nd oothmD eFFqF nd groomD FwF nd hriverD FF nd hrinkwterD wFtF nd vorenteD xFFpF nd gorteseD vF nd ottD xF nd gollessD wF nd heferD eF nd ylorD iFxF nd uonstntopoulosD sFF nd ellenD tFF nd fldryD sF nd frnesD vF nd fuerD eFiF nd flndErwthornD tF nd floomD tFF nd frooksD eFwF nd froughD F nd geilD qF nd gouhD F nd grotonD hF nd hviesD F nd illisD F nd pogrtyD vFwFF nd posterD gF nd qlzerookD uF nd qoodwinD wF nd qreenD eF nd qunwrdhnD wFvF nd rmptonD iF nd roD sFEF nd ropkinsD eFwF nd uewleyD vF nd vwreneD tFF nd veonEvlD FqF nd veslieD F nd wilroyD F nd vewisD qF nd viskeD tF nd v¡ opezE¡ nhezD ¡ eFF nd whjnD F nd wedlingD eFwF nd wetlfeD xF nd weyerD wF nd wouldD tF nd yreshkowD hF nd y9ooleD F nd ryD wF nd ihrdsD FxF nd hnksD F nd hrpD F nd weetD FwF nd homsD eFhF nd oniniD gF nd lherD gFtF @PHISA 9he ews qlxy urvey X instrument spei(tion nd trget seletionF9D wonthly noties of the oyl estronomil oietyFD RRU @QAF ppF PVSUEPVUWF Further information on publisher's website: Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. ABSTRACTThe SAMI Galaxy Survey will observe 3400 galaxies with the Sydney-AAO Multi-object Integral-field spectrograph (SAMI) on the Anglo-Australian Telescope in a 3-yr survey which began in 2013. We present the throughput of the SAMI system, the science basis and specifications for the target selection, the survey observation plan and the combined properties of the selected galaxies. The survey includes four volume-limited galaxy samples based on cuts in a proxy for stellar mass, along with low-stellar-mass dwarf galaxies all selected from the Galaxy And Mass Assembly (GAMA) survey. The GAMA regions were selected because of the vast array of ancillary data available, including ultraviolet through to radio bands. These fields are on the celestial equator at 9, 12 and 14.5 h, and cover a total of 144 deg 2 (in GAMA-I). Higher density environments are also included with the addition of eight clusters. The clusters have spectroscopy from 2-degree Field Galaxy Redshift Survey (2dFGRS) and Sloan Digital Sky Survey (SDSS) and photometry in regions covered by the SDSS and/or VLT Survey Telescope/ATLAS. The aim is to cover a broad range in stellar mass and environment, and therefore the primary survey targets cover redshifts 0.004 < z < 0.095, magnitudes r pet < 19.4, stellar masses 10 7 -10 12 M , and environments from isolated field galaxies through groups to clusters of ∼10 15 M .

Ongoing or recent star formation in galaxies is known to increase with increasing projected distance from the centre of a cluster out to several times its virial radius (Rv). Using a complete sample (Mr≤−20.5, 0.02 ≤z≤ 0.15) of galaxies in and around 268 clusters from the Sloan Digital Sky Survey's Fourth Data Release, we investigate how, at a given projected radius from the cluster centre, the stellar mass and star formation properties of a galaxy depend on its absolute line‐of‐sight velocity in the cluster rest frame, |vLOS|. We find that for projected radii R < 0.5 Rv, the fraction of high‐mass non‐brightest cluster galaxies increases towards the centre for low |vLOS|, which may be the consequence of the faster orbital decay of massive galaxies by dynamical friction. At a given projected radius, the fraction of Galaxies with Ongoing or Recent (<1–3 Gyr) Efficient Star Formation [GORES; with EW(Hδ) > 2 Å & Dn4000 > 1.5] is slightly but significantly lower for low |vLOS| galaxies than for their high‐velocity counterparts. We study these observational trends with the help of a dark matter (DM) cosmological simulation. We classify DM particles as virial, infall and backsplash according to their present positions in (r, vr) radial phase space and measure the frequencies of each class in cells of (R, |vLOS|) projected phase space. As expected, the virial class dominates at projected radii R < Rv, while the infall particles dominate outside, especially at high |vLOS|. However, the backsplash particles account for at least one‐third (half) of all particles at projected radii slightly greater than the virial radius and |vLOS| < σv (|vLOS| ≪σv). The deprojection of the GORES fraction leads to a saturated linear increase with radius. We fit simple models of the fraction of GORES as a function of class only or class and distance to the cluster centre (as in our deprojected fraction). While GORES account for 18 ± 1 per cent of all galaxies within the virial cylinder, in our best‐fitting model, they account for 13 ± 1 per cent of galaxies within the virial sphere, 11 ± 1 per cent of the virial population, 34 ± 1 per cent of the distant (for projected radii R < 2 Rv) infall population and 19 ± 4 per cent of the backsplash galaxies. Also, 44 ± 2 per cent of the GORES within the virial cylinder are outside the virial sphere. These fractions are very robust to the precise good‐fitting model and to our scheme for assigning simulation particle classes according to their positions in radial phase space (except for two of our models, where the fraction of GORES reaches 27 ± 4 per cent). Given the 1–3 Gyr lookback time of our GORES indicators, these results suggest that star formation in a galaxy is almost completely quenched in a single passage through the cluster.

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We use a highly complete subset of the GAMA-II redshift sample to fully describe the stellar mass dependence of close-pairs and mergers between 10 8 M and 10 12 M . Using the analytic form of this fit we investigate the total stellar mass accreting onto more massive galaxies across all mass ratios. Depending on how conservatively we select our robust merging systems, the fraction of mass merging onto more massive companions is 2.0%-5.6%.Using the GAMA-II data we see no significant evidence for a change in the closepair fraction between redshift z = 0.05-0.2. However, we find a systematically higher fraction of galaxies in similar mass close-pairs compared to published results over a similar redshift baseline. Using a compendium of data and the function γ M = A(1+z) m to predict the major close-pair fraction, we find fitting parameters of A = 0.021 ± 0.001 and m = 1.53 ± 0.08, which represents a higher low-redshift normalisation and shallower power-law slope than recent literature values.We find that the relative importance of in-situ star-formation versus galaxy merging is inversely correlated, with star-formation dominating the addition of stellar material below M * and merger accretion events dominating beyond M * .We find mergers have a measurable impact on the whole extent of the GSMF, manifest as a deepening of the 'dip' in the GSMF over the next ∼Gyr and an increase in M * by as much as 0.01-0.05 dex.