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Chiara Tonini

Publications and source records attributed to Chiara Tonini.

At least 19 recordsLinked to original sources

The SAMI Galaxy Survey: Spatially Resolving the Main Sequence of Star Formation

We present the ~800 star formation rate maps for the SAMI Galaxy Survey based on Hα emission maps, corrected for dust attenuation via the Balmer decrement, that are included in the SAMI Public Data Release 1. We mask out spaxels contaminated by non-stellar emission using the [O III]/Hβ, [N II]/Hα, [S II]/Hα, and [O I]/Hα line ratios. Using these maps, we examine the global and resolved star-forming main sequences of SAMI galaxies as a function of morphology, environmental density, and stellar mass. Galaxies further below the star-forming main sequence are more likely to have flatter star formation profiles. Early-type galaxies split into two populations with similar stellar masses and central stellar mass surface densities. The main sequence population has centrally-concentrated star formation similar to late-type galaxies, while galaxies >3σ below the main sequence show significantly reduced star formation most strikingly in the nuclear regions. The split populations support a two-step quenching mechanism, wherein halo mass first cuts off the gas supply and remaining gas continues to form stars until the local stellar mass surface density can stabilize the reduced remaining fuel against further star formation. Across all morphologies, galaxies in denser environments show a decreased specific star formation rate from the outside in, supporting an environmental cause for quenching, such as ram-pressure stripping or galaxy interactions.

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The SAMI Galaxy Survey: Global stellar populations on the size-mass plane

We present an analysis of the global stellar populations of galaxies in the SAMI Galaxy Survey. Our sample consists of 1319 galaxies spanning four orders of magnitude in stellar mass and includes all morphologies and environments. We derive luminosity-weighted, single stellar population equivalent stellar ages, metallicities and alpha enhancements from spectra integrated within one effective radius apertures. Variations in galaxy size explain the majority of the scatter in the age--mass and metallicity--mass relations. Stellar populations vary systematically in the plane of galaxy size and stellar mass, such that galaxies with high stellar surface mass density are older, more metal-rich and alpha-enhanced than less dense galaxies. Galaxies with high surface mass densities have a very narrow range of metallicities, however, at fixed mass, the spread in metallicity increases substantially with increasing galaxy size (decreasing density). We identify residual correlations with morphology and environment. At fixed mass and size, galaxies with late-type morphologies, small bulges and low Sersic n are younger than early-type, high n, high bulge-to-total galaxies. Age and metallicity both show small residual correlations with environment; at fixed mass and size, galaxies in denser environments or more massive halos are older and somewhat more metal rich than those in less dense environments. We connect these trends to evolutionary tracks within the size--mass plane.

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The SAMI Galaxy Survey: Data Release One with Emission-line Physics Value-Added Products

We present the first major release of data from the SAMI Galaxy Survey. This data release focuses on the emission-line physics of galaxies. Data Release One includes data for 772 galaxies, about 20% of the full survey. Galaxies included have the redshift range 0.004 < z < 0.092, a large mass range (7.6 < log(Mstellar/M$_\odot$) < 11.6), and star-formation rates of 10^-4 to 10^1\ M$_\odot$/yr. For each galaxy, we include two spectral cubes and a set of spatially resolved 2D maps: single- and multi-component emission-line fits (with dust extinction corrections for strong lines), local dust extinction and star-formation rate. Calibration of the fibre throughputs, fluxes and differential-atmospheric-refraction has been improved over the Early Data Release. The data have average spatial resolution of 2.16 arcsec (FWHM) over the 15~arcsec diameter field of view and spectral (kinematic) resolution R=4263 (sigma=30km/s) around Halpha. The relative flux calibration is better than 5\% and absolute flux calibration better than $\pm0.22$~mag, with the latter estimate limited by galaxy photometry. The data are presented online through the Australian Astronomical Observatory's Data Central.

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The SAMI Galaxy Survey: Revising the Fraction of Slow Rotators in IFS Galaxy Surveys

The fraction of galaxies supported by internal rotation compared to galaxies stabilized by internal pressure provides a strong constraint on galaxy formation models. In integral field spectroscopy surveys, this fraction is biased because survey instruments typically only trace the inner parts of the most massive galaxies. We present aperture corrections for the two most widely used stellar kinematic quantities $V/σ$ and $λ_{R}$. Our demonstration involves integral field data from the SAMI Galaxy Survey and the ATLAS$^{\rm{3D}}$ Survey. We find a tight relation for both $V/σ$ and $λ_{R}$ when measured in different apertures that can be used as a linear transformation as a function of radius, i.e., a first-order aperture correction. We find that $V/σ$ and $λ_{R}$ radial growth curves are well approximated by second order polynomials. By only fitting the inner profile (0.5$R_{\rm{e}}$), we successfully recover the profile out to one $R_{\rm{e}}$ if a constraint between the linear and quadratic parameter in the fit is applied. However, the aperture corrections for $V/σ$ and $λ_{R}$ derived by extrapolating the profiles perform as well as applying a first-order correction. With our aperture-corrected $λ_{R}$ measurements, we find that the fraction of slow rotating galaxies increases with stellar mass. For galaxies with $\log M_{*}/M_{\odot}>$ 11, the fraction of slow rotators is $35.9\pm4.3$ percent, but is underestimated if galaxies without coverage beyond one $R_{\rm{e}}$ are not included in the sample ($24.2\pm5.3$ percent). With measurements out to the largest aperture radius the slow rotator fraction is similar as compared to using aperture corrected values ($38.3\pm4.4$ percent). Thus, aperture effects can significantly bias stellar kinematic IFS studies, but this bias can now be removed with the method outlined here.

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The SAMI Galaxy Survey: mass as the driver of the kinematic morphology - density relation in clusters

We examine the kinematic morphology of early-type galaxies (ETGs) in eight galaxy clusters in the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey. The clusters cover a mass range of 14.2<log(M_200/M_odot)<15.2 and we measure spatially-resolved stellar kinematics for 315 member galaxies with stellar masses 10.0<log(M_*/M_odot)<11.7 within 1R_200 of the cluster centers. We calculate the spin parameter, lambda_R and use that to classify the kinematic morphology of the galaxies as fast or slow rotators. The total fraction of slow rotators in the early-type galaxy population, F_SR=0.14+/-0.02 and does not depend on host cluster mass. Across the eight clusters, the fraction of slow rotators increases with increasing local overdensity. We also find that the slow-rotator fraction increases at small clustercentric radii (R_cl<0.3R_200), and note that there is also an increase in slow-rotator fraction at R_cl~0.6R_200. The slow rotators at these larger radii reside in cluster substructure. We find the strongest increase in slow-rotator fraction occurs with increasing stellar mass. After accounting for the strong correlation with stellar mass, we find no significant relationship between spin parameter and local overdensity in the cluster environment. We conclude that the primary driver for the kinematic morphology--density relationship in galaxy clusters is the changing distribution of galaxy stellar mass with local environment. The presence of slow rotators in substructure suggests that the cluster kinematic morphology--density relationship is a result of mass segregation of slow-rotating galaxies forming in groups that later merge with clusters and sink to the cluster center via dynamical friction.

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Galaxy and Mass Assembly (GAMA): halo formation times and halo assembly bias on the cosmic web

We present evidence for halo assembly bias as a function of geometric environment. By classifying GAMA galaxy groups as residing in voids, sheets, filaments or knots using a tidal tensor method, we find that low-mass haloes that reside in knots are older than haloes of the same mass that reside in voids. This result provides direct support to theories that link strong halo tidal interactions with halo assembly times. The trend with geometric environment is reversed at large halo mass, with haloes in knots being younger than haloes of the same mass in voids. We find a clear signal of halo downsizing - more massive haloes host galaxies that assembled their stars earlier. This overall trend holds independently of geometric environment. We support our analysis with an in-depth exploration of the L-Galaxies semi-analytic model, used here to correlate several galaxy properties with three different definitions of halo formation time. We find a complex relationship between halo formation time and galaxy properties, with significant scatter. We confirm that stellar mass to halo mass ratio, specific star-formation rate and mass-weighed age are reasonable proxies of halo formation time, especially at low halo masses. Instantaneous star-formation rate is a poor indicator at all halo masses. Using the same semi-analytic model, we create mock spectral observations using complex star-formation and chemical enrichment histories, that approximately mimic GAMA's typical signal-to-noise and wavelength range. We use these mocks to assert how well potential proxies of halo formation time may be recovered from GAMA-like spectroscopic data.

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The growth of disks and bulges during hierarchical galaxy formation. II: metallicity, stellar populations and dynamical evolution

We investigate the properties of the stellar populations of model galaxies as a function of galaxy evolutionary history and angular momentum content. We use the new semi-analytic model presented in Tonini et al. (2016). This new model follows the angular momentum evolution of gas and stars, providing the base for a new star formation recipe, and treatment of the effects of mergers that depends on the central galaxy dynamical structure. We find that the new recipes have the effect of boosting the efficiency of the baryonic cycle in producing and recycling metals, as well as preventing minor mergers from diluting the metallicity of bulges and ellipticals. The model reproduces the stellar mass - stellar metallicity relation for galaxies above 1e10 solar masses, including Brightest Cluster Galaxies. Model disks, galaxies dominated by instability-driven components, and merger-driven objects each stem from different evolutionary channels. These model galaxies therefore occupy different loci in the galaxy mass-size relation, which we find to be in accord with the Atlas 3D classification of disk galaxies, fast rotators and slow rotators. We find that the stellar populations' properties depend on the galaxy evolutionary type, with more evolved stellar populations being part of systems that have lost or dissipated more angular momentum during their assembly history.

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The SAMI Galaxy Survey: Revisiting Galaxy Classification Through High-Order Stellar Kinematics

Recent cosmological hydrodynamical simulations suggest that integral field spectroscopy can connect the high-order stellar kinematic moments h3 (~skewness) and h4 (~kurtosis) in galaxies to their cosmological assembly history. Here, we assess these results by measuring the stellar kinematics on a sample of 315 galaxies, without a morphological selection, using 2D integral field data from the SAMI Galaxy Survey. A proxy for the spin parameter ($λ_{R_e}$) and ellipticity ($ε_e$) 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. 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 $λ_{R_e}-ε_e$ 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. 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.

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The growth of disks and bulges during hierarchical galaxy formation. I: fast evolution vs secular processes

We present a theoretical model for the evolution of mass, angular momentum and size of galaxy disks and bulges, and we implement it into the semi-analytic galaxy formation code SAGE. The model follows both secular and violent evolutionary channels, including smooth accretion, disk instabilities, minor and major mergers. We find that the combination of our recipe with hierarchical clustering produces two distinct populations of bulges: merger-driven bulges, akin to classical bulges and ellipticals, and instability-driven bulges, akin to secular (or pseudo-)bulges. The model mostly reproduces the mass-size relation of gaseous and stellar disks, the evolution of the mass-size relation of ellipticals, the Faber-Jackson relation, and the magnitude-colour diagram of classical and secular bulges. The model predicts only a small overlap of merger-driven and instability-driven components in the same galaxy, and predicts different bulge types as a function of galaxy mass and disk fraction. Bulge type also affects the star formation rate and colour at a given luminosity. The model predicts a population of merger-driven red ellipticals that dominate both the low-mass and high-mass ends of the galaxy population, and span all dynamical ages; merger-driven bulges in disk galaxies are dynamically old and do not interfere with subsequent evolution of the star-forming component. Instability-driven bulges dominate the population at intermediate galaxy masses, especially thriving in massive disks. The model green valley is exclusively populated by instability-driven bulge hosts. Through the present implementation the mass accretion history is perceivable in the galaxy structure, morphology and colours.

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Semi-Analytic Galaxy Evolution (SAGE): Model Calibration and Basic Results

This paper describes a new publicly available codebase for modelling galaxy formation in a cosmological context, the "Semi-Analytic Galaxy Evolution" model, or SAGE for short. SAGE is a significant update to that used in Croton et al. (2006) and has been rebuilt to be modular and customisable. The model will run on any N-body simulation whose trees are organised 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: 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.

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The Theoretical Astrophysical Observatory: Cloud-Based Mock Galaxy Catalogues

We introduce the Theoretical Astrophysical Observatory (TAO), an online virtual laboratory that houses mock observations of galaxy survey data. Such mocks have become an integral part of the modern analysis pipeline. However, building them requires an expert knowledge of galaxy modelling and simulation techniques, significant investment in software development, and access to high performance computing. These requirements make it difficult for a small research team or individual to quickly build a mock catalogue suited to their needs. To address this TAO offers access to multiple cosmological simulations and semi-analytic galaxy formation models from an intuitive and clean web interface. Results can be funnelled through science modules and sent to a dedicated supercomputer for further processing and manipulation. These modules include the ability to (1) construct custom observer light-cones from the simulation data cubes; (2) generate the stellar emission from star formation histories, apply dust extinction, and compute absolute and/or apparent magnitudes; and (3) produce mock images of the sky. All of TAO's features can be accessed without any programming requirements. The modular nature of TAO opens it up for further expansion in the future.

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The Fundamental Manifold of spiral galaxies: ordered versus random motions and the morphology dependence of the Tully-Fisher relation

(Abridged) We investigate the morphology dependence of the Tully-Fisher relation, and the expansion of the relation into a three-dimensional manifold defined by luminosity, total circular velocity and a third dynamical parameter, to fully characterise spiral galaxies across all morphological types. We use a semi-analytic hierarchical model of galaxy evolution to build the theoretical TF relation. With this tool, we analyse a unique dataset of galaxies for which we cross-match luminosity with total circular velocity and central velocity dispersion. We provide a theoretical framework to calculate such measurable quantities from semi-analytic models. We establish the morphology dependence of the TF relation in both model and data. We analyse the dynamical properties of the model galaxies and determine that the parameter 'sigma/Vc', i.e. the ratio between random and total motions defined by velocity dispersion and circular velocity, accurately characterises the varying slope of the TF relation for different model galaxy types. We apply these dynamical cuts to the observed galaxies and find that such selection produces a differential slope of the TF relation. The TF slope in different ranges of 'sigma/Vc' is consistent with that for the photometric classification in Sa, Sb, Sc. We conclude that 'sigma/Vc' is a good parameter to classify galaxy type, and we argue that such classification based on dynamics more closely mirrors the physical properties of the observed galaxies, compared to visual classification. We also argue that dynamical classification is useful for samples where eye inspection is not reliable or impractical. We conclude that 'sigma/Vc' is a suitable parameter to characterise the hierarchical assembly history that determines the disk-to-bulge ratio, and to expand the TF relation into a three-dimensional manifold, defined by luminosity, circular velocity and 'sigma/Vc'.

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Recovering galaxy stellar population properties from broad-band spectral energy distribution fitting II. The case with unknown redshift

(Abridged) In a recent work we explored the dependence of galaxy stellar population properties derived from broad-band spectral energy distribution fitting on the fitting parameters, e.g. SFHs, age grid, metallicity, IMF, dust reddening, reddening law, filter setup and wavelength coverage. In this paper we consider also redshift as a free parameter in the fit and study whether one can obtain reasonable estimates of photometric redshifts and stellar population properties at once. We use mock star-forming as well as passive galaxies placed at various redshifts (0.5 to 3) as test particles. Mock star-forming galaxies are extracted from a semi-analytical galaxy formation model. We show that for high-z star-forming galaxies photometric redshifts, stellar masses and reddening can be determined simultaneously when using a broad wavelength coverage and a wide template setup in the fit. Masses are similarly well recovered (median ~ 0.2 dex) as at fixed redshift. For old galaxies with little recent star formation masses are better recovered than in the fixed redshift case, such that the median recovered stellar mass improves by up to 0.3 dex whereas the uncertainty in the redshift accuracy increases by only ~ 0.05. However, a failure in redshift recovery also means a failure in mass recovery. As at fixed redshift mismatches in SFH and degeneracies between age, dust and now also redshift cause underestimated ages, overestimated reddening and underestimated masses. Stellar masses are best determined at low redshift without reddening in the fit (median underestimation ~ 0.1 dex for similarly well recovered redshifts). Not surprisingly, the recovery of properties is substantially better for passive galaxies. In all cases, the recovery of physical parameters is crucially dependent on the wavelength coverage adopted in the fitting. Scaling relations for the transformation of stellar masses are provided.

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The effect of thermally pulsating asymptotic giant branch stars on the evolution of the rest-frame near-infrared galaxy luminosity function

We address the fundamental question of matching the rest-frame K-band luminosity function (LF) of galaxies over the Hubble time using semi-analytic models, after modification of the stellar population modelling. We include the Maraston evolutionary synthesis models, that feature a higher contribution by the Thermally Pulsating - Asymptotic Giant Branch (TP-AGB) stellar phase, into three different semi-analytic models, namely the De Lucia and Blaizot version of the Munich model, MORGANA and the Menci model. We leave all other input physics and parameters unchanged. We find that the modification of the stellar population emission can solve the mismatch between models and the observed rest-frame K-band luminosity from the brightest galaxies derived from UKIDSS data at high redshift. For all explored semi-analytic models this holds at the redshifts - between 2 and 3 - where the discrepancy was recently pointed out. The reason for the success is that at these cosmic epochs the model galaxies have the right age (~1 Gyr) to contain a well-developed TP-AGB phase which makes them redder without the need of changing their mass or age. At the same time, the known overestimation of the faint end is enhanced in the K-band when including the TP-AGB contribution. At lower redshifts (z<2) some of the explored models deviate from the data. This is due to too short merging timescales and inefficient 'radio-mode' AGN feedback. Our results show that a strong evolution in mass predicted by hierarchical models is compatible with no evolution on the bright-end of the K-band LF from z=3 to the local universe. This means that, at high redshifts and contrary to what is commonly accepted, K-band emission is not necessarily a good tracer of galaxy mass.

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The metallicity bimodality of globular cluster systems: a test of galaxy assembly and of the evolution of the galaxy mass-metallicity relation

(Abridged) We build a theoretical model to study the origin of the globular cluster metallicity bimodality in the hierarchical galaxy assembly scenario, based on the observed galaxy mass-[O/H] relation and the galaxy stellar mass function up to z ~4, and on theoretical merger rates. We derive a new galaxy [Fe/H]-M(star) relation as a function of z, and by assuming that GCs share the metallicity of their parent galaxy when they form, we populate the merger tree with GCs. We perform a series of Monte-Carlo simulations of the galaxy assembly, and study the properties of the final GC population as a function of galaxy mass, assembly and star formation history, and under different assumptions for the evolution of the galaxy mass-[Fe/H] relation. The main results are: 1) The hierarchical clustering scenario naturally predicts a metallicity bimodality in the galaxy GC population: the metal-rich GCs are formed in the galaxy main progenitor around z~2, and the metal-poor GCs are accreted from satellites and formed at z~3-4. 2) The model reproduces the observed relations for the metallicity of the metal-rich and metal-poor GCs as a function of galaxy mass. The positions of the metal-poor and metal-rich peaks depend exclusively on the evolution of the galaxy mass-[Fe/H] relation and the [O/Fe], both of which can be constrained by this method. We find that the galaxy [O/Fe] evolves linearly with z from a value of ~0.5 at z~4 to a value of ~0.1 at z=0. 3) Given a galaxy mass, the relative strength of the metal-rich and metal-poor peaks depends exclusively on the galaxy assembly and star formation history: galaxies in denser environments and/or early types galaxies show a larger fraction of metal-poor GCs, while galaxies with a sparse merger history and/or late type galaxies are dominated by metal-rich GCs. 4) The GC metallicity bimodality disappears for galaxy masses below M(star)~1e9, and for z>2.

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The evolution of Brightest Cluster Galaxies in a hierarchical universe

We investigate the evolution of Brightest Cluster Galaxies (BCGs) from redshift z~1.6 to z~0. We use the semi-analytic model of Croton et al. (2006) with a new spectro-photometric model based on the Maraston (2005) stellar populations and a new recipe for the dust extinction. We compare the model predictions of the K-band luminosity evolution and the J-K, V-I and I-K colour evolution with a series of datasets, including Collins et al. (Nature, 2009) who argued that semi-analytic models based on the Millennium simulation cannot reproduce the red colours and high luminosity of BCGs at z>1. We show instead that the model is well in range of the observed luminosity and correctly reproduces the colour evolution of BCGs in the whole redshift range up to z~1.6. We argue that the success of the semi-analytic model is in large part due to the implementation of a more sophisticated spectro-photometric model. An analysis of the model BCGs shows an increase in mass by a factor ~2 since z~1, and star formation activity down to low redshifts. While the consensus regarding BCGs is that they are passively evolving, we argue that this conclusion is affected by the degeneracy between star formation history and stellar population models used in SED-fitting, and by the inefficacy of toy-models of passive evolution to capture the complexity of real galaxies, expecially those with rich merger histories like BCGs. Following this argument, we also show that in the semi-analytic model the BCGs show a realistic mix of stellar populations, and that these stellar populations are mostly old. In addition, the age-redshift relation of the model BCGs follows that of the universe, meaning that given their merger history and star formation history, the ageing of BCGs is always dominated by the ageing of their stellar populations. In a LambdaCDM universe, we define such evolution as "passive in the hierarchical sense".

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Recovering galaxy stellar population properties from broad-band spectral energy distribution fitting

(Abridged) We explore the dependence of galaxy stellar population properties derived from broad-band SED-fitting - such as age, stellar mass, dust reddening, etc. - on a variety of parameters, such as SFHs, metallicity, IMF, dust reddening and reddening law, and wavelength coverage. Mock galaxies serve as test particles. We confirm our earlier results based on real z=2 galaxies, that usually adopted τ-models lead to overestimate the SFR and to underestimate the stellar mass. Here, we show that - for star-forming galaxies - ages, masses and reddening, can be well determined simultaneously only when the correct SFH is identified. This is the case for inverted-τ-models at high-z, for which we find that the mass recovery (at fixed IMF) is as good as ~0.04 dex. Since the right SFH is usually unknown we quantify offsets generated by adopting standard fitting setups. Stellar masses are generally underestimated resulting from underestimating ages. For fitting setups with a variety of SFHs the median mass recovery at z ~ 2-3 is as decent as ~0.1 dex, albeit with large scatter. The situation worsens towards lower redshifts because of the variety of possible SFHs and ages (~0.6 dex at z=0.5). A practical trick to improve upon this is to exclude reddening from the fitting to avoid unrealistically young and dusty solutions. Reddening and SFRs should then be determined by a separate fit. As expected, the recovery of properties is better for passive galaxies. For the two galaxy types the parameter recovery is optimal for a wavelength coverage from the rest-frame UV to the rest-frame near-IR. We quantify the effect of narrowing the wavelength coverage or adding/removing filters which can be useful for planning observational surveys. Finally, we provide scaling relations that allow the transformation of stellar masses obtained using different template fitting setups and stellar population models.

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The hierarchical build-up of the Tully-Fisher relation

We use the semi-analytic model GalICS to predict the Tully-Fisher relation in the B, I and for the first time, in the K band, and its evolution with redshift, up to z~1. We refined the determination of the disk galaxies rotation velocity, with a dynamical recipe for the rotation curve, rather than a simple conversion from the total mass to maximum velocity. The new recipe takes into account the disk shape factor, and the angular momentum transfer occurring during secular evolution leading to the formation of bulges. This produces model rotation velocities that are lower by ~20-25% for the majority of the spirals. We implemented stellar population models with a complete treatment of the TP-AGB, which leads to a revision of the mass-to-light ratio in the near-IR. I/K band luminosities increase by ~0.3/0.5 mags at redshift z=0 and by ~0.5/1 mags at z=3. With these two new recipes in place, the comparison between the predicted Tully-Fisher relation with a series of datasets in the optical and near-IR, at redshifts between 0 and 1, is used as a diagnostics of the assembly and evolution of spiral galaxies in the model. At 0.4<z<1.2 the match between the new model and data is remarkably good, especially for later-type spirals (Sb/Sc). At z=0 the new model shows a net improvement in comparison with its original version of 2003, and in accord with recent observations in the K band, the model Tully-Fisher also shows a morphological differentiation. However, in all bands the z=0 model Tully-Fisher is too bright. We argue that this behaviour is caused by inadequate star formation histories in the model galaxies at low redshifts. The star-formation rate declines too slowly, due to continuous gas infall that is not efficiently suppressed. An analysis of the model disk scale lengths, at odds with observations, hints to some missing physics in the modeling of disk formation inside dark matter halos.

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