In the current CDM cosmological scenario, N-body simulations provide us with a universal mass profile, and consequently a universal equilibrium circular velocity of the virialized objects, as galaxies. In this paper we obtain, by combining kinematical data of their inner regions with global observational properties, the universal rotation curve of disc galaxies and the corresponding mass distribution out to their virial radius. This curve extends the results of Paper I, concerning the inner luminous regions of Sb-Im spirals, out to the edge of the galaxy haloes.

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 .

This paper describes a new publicly available codebase for modeling galaxy formation in a cosmological context, the "Semi-Analytic Galaxy Evolution" model, or SAGE for short.5 SAGE is a significant update to the 2006 model of Croton et al. and has been rebuilt to be modular and customizable. The model will run on any N-body simulation whose trees are organized in a supported format and contain a minimum set of basic halo properties. In this work, we present the baryonic prescriptions implemented in SAGE to describe the formation and evolution of galaxies, and their calibration for three N-body simulations: Millennium, Bolshoi, and GiggleZ. Updated physics include the following: gas accretion, ejection due to feedback, and reincorporation via the galactic fountain; a new gas cooling-radio mode active galactic nucleus (AGN) heating cycle; AGN feedback in the quasar mode; a new treatment of gas in satellite galaxies; and galaxy mergers, disruption, and the build-up of intra-cluster stars. Throughout, we show the results of a common default parameterization on each simulation, with a focus on the local galaxy population.

Fitting synthetic spectral energy distributions (SEDs) to the multiband photometry of galaxies to derive their star formation rates (SFRs), stellar masses, ages, etc. requires making a priori assumptions about their star formation histories (SFHs). A widely adopted parametrization of the SFH, the so‐called τ models where SFR ∝ e−t/τ is shown to lead to unrealistically low ages when applied to a sample of actively star‐forming galaxies at z∼ 2, a problem shared by other SFHs when the age is left as a free parameter in the fitting procedure. This happens because the SED of such galaxies, at all wavelengths, is dominated by their youngest stellar populations, which outshine the older ones. Thus, the SED of such galaxies conveys little information on the beginning of star formation (SF), i.e. on the age of their oldest stellar populations. To cope with this problem, besides τ models (hereafter called direct‐τ models), we explore a variety of SFHs, such as constant SFR and inverted‐τ models (with SFR ∝ e+t/τ), along with various priors on age, including assuming that SF started at high redshift in all the galaxies in the test sample. We find that inverted‐τ models with such latter assumption give SFRs and extinctions in excellent agreement with the values derived using only the UV part of the SED, which is the one most sensitive to ongoing SF and reddening. These models are also shown to accurately recover the SFRs and masses of mock galaxies at z∼ 2 constructed from semi‐analytic models, which we use as a further test. All other explored SFH templates do not fulfil these two tests as well as inverted‐τ models do. In particular, direct‐τ models with unconstrained age in the fitting procedure overestimate SFRs and underestimate stellar mass, and would exacerbate an apparent mismatch between the cosmic evolution of the volume densities of SFR and stellar mass. We conclude that for high‐redshift star‐forming galaxies an exponentially increasing SFR with a high formation redshift is preferable to other forms of the SFH so far adopted in the literature.