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We measure the clustering of low-redshift Sloan Digital Sky Survey (SDSS) galaxies as a function of stellar mass (⁠|$10.0\lt \log (M_*/\mathrm{M}_\odot)\lt 11.5$|⁠) and specific star formation rate (sSFR) and compare the results to models of the galaxy–halo connection. We find that the autocorrelation functions of central galaxies exhibit little dependence on sSFR, with the well-known stronger clustering of quiescent galaxies mainly attributable to satellites. Because halo assembly history is known to affect distinct halo clustering, this result implies that there is little net correlation between halo assembly history and central galaxy sSFR. However, cross-correlations with satellites are stronger for quiescent centrals than star-forming centrals, consistent with quiescent centrals having more satellites in their haloes at fixed |$M_*$|⁠ , as found in SDSS group catalogues. We model the galaxy–halo connection in an N -body simulation by assigning sSFRs to central galaxies in three different ways. Two of the models depend on halo assembly history (being based on halo accretion rate or concentration), while the third is independent of halo assembly history (being based on peak halo circular velocity, |$V_\text{peak}$|⁠ , a proxy for halo mass). All three models replicate the observed autocorrelations of central galaxies, while only the |$V_\text{peak}$| model reproduces the observed cross-correlations with satellites. This further suggests that the effects of halo assembly history may not be easily seen in autocorrelations of centrals and implies that a more complete understanding of central galaxy clustering may require more than autocorrelations of centrals alone. Additionally, the good agreement with the |$V_\text{peak}$| model supports the idea that quiescent central galaxies reside in more massive haloes than star-forming central galaxies at fixed |$M_*$|⁠. [ABSTRACT FROM AUTHOR]

We investigate the relation between galaxy structure and star formation rate (SFR) in a sample of |$\sim 2.9\times 10^{4}$| central galaxies with |$z\lt 0.0674$| and axial ratios |$b/a\gt 0.5$|⁠. The star-forming main sequence (SFMS) shows a bend around the stellar mass of |$M_\ast \le {}M_c=2\times 10^{10}{}{\rm M}_{\odot }$|⁠. At |$M_\ast \le {}M_c$|⁠ , the SFMS follows a power-law |$\text{SFR}\propto {}M_\ast ^{0.85}$|⁠ , while at higher masses it flattens. |$M_c$| corresponds to a dark matter halo mass of |$M_\text{vir}\sim {}10^{11.8}{\rm M}_{\odot }$| where virial shocks occurs. Some galaxy structure (e.g. half-light radius, |$R_e$|⁠) exhibits a non-monotonic dependence across the SFMS at a fixed |$M_\ast$|⁠. We find |$\text{SFR}\propto {R_e^{-0.28}}$| at fixed |$M_\ast$|⁠ , consistent with the global Kennicutt–Schmidt (KS) law. This finding suggests that galaxy sizes contribute to the scatter of the SFMS. However, at |$M_\ast \gt M_c$| the relationship between SFR and |$R_e$| diminishes. Low-mass galaxies above the mean of the SFMS have smaller radii, exhibit compact and centrally concentrated profiles resembling green valley (GV) and quiescent galaxies at the same mass, and have higher |$M_{\text{H}_2}{/}M_\rm{H\,{\small I}}$|⁠. Conversely, those below the SFMS exhibit larger radii, lower densities, have no GV or quiescent counterparts at their mass and have lower |$M_{\text{H}_2}/M_\rm{H\,{\small I}}$|⁠. The above data suggest two pathways for quenching low-mass galaxies, |$M_\ast \le {}M_c$|⁠ : a fast one that changes the morphology on the SFMS and a slow one that does not. Above |$M_c$|⁠ , galaxies below the SFMS resemble GV and quiescent galaxies structurally, implying that they undergo a structural transformation already within the SFMS. For these massive galaxies, CG are strongly bimodal, with SFMS galaxies exhibiting negative colour gradients, suggesting most star formation occurs in their outskirts, maintaining them within the SFMS. [ABSTRACT FROM AUTHOR]

We present a new cosmologically motivated mock redshift survey of the dusty star-forming galaxy population. Our mock survey is based on the Bolshoi– Planck dark matter halo simulation and covers an area of 5.3 deg2. Using a semi-empirical approach, we generate a light-cone and populate the dark matter haloes with galaxies. Infrared properties are assigned to the galaxies based on theoretical and empirical relations from the literature. Additionally, background galaxies are gravitationally lensed by dark matter haloes along the line of sight assuming a point-mass model approximation. We characterize the mock survey by measuring the star formation rate density, integrated number counts, redshift distribution, and infrared luminosity function. When compared with single-dish and interferometric observations, the predictions from our mock survey closely follow the compiled results from the literature. We have also directed this study towards characterizing one of the extragalactic legacy surveys to be observed with the TolTEC camera at the Large Millimeter Telescope: the 0.8 sq. degree Ultra Deep Survey, with expected depths of 0.025, 0.018, and 0.012 mJy beam−1 at 1.1, 1.4, and 2.0 mm. Exploiting the clustering information in our mock survey, we investigate its impact on the effect of flux boosting by the fainter population of dusty galaxies, finding that clustering can increase the median boosting by 0.5  per cent at 1.1 mm, 0.8  per cent at 1.4 mm, and 2.0  per cent at 2.0 mm, and with higher dispersion. [ABSTRACT FROM AUTHOR]

Using spatially resolved fossil record analysis on a large sample of 'red and dead' elliptical galaxies (classical ellipticals, CLEs) from the MaNGA/SDSS-IV DR15 survey, we reconstruct the archaeological evolution of their radial gradients in mass-to-luminosity ratio (M / L), g − r colour, and specific star formation (SF) rate. We also calculate other metrics that quantify the inside-out SF quenching and external mass growth processes. The M / L gradients, ∇Υ⋆, are approximately flat at high look-back times (t lb), but then they become negative and steeper until an epoch, when this trend reverses. These trends are shifted to later epochs the less massive the galaxies are. Colour gradients follow qualitatively similar trends. We find that these trends are mainly driven by strong inside-out quenching, without significant outer growth or structural changes overall. Our results suggest a scenario where the main progenitors of local CLE galaxies evolved quasi-passively after an early dissipative phase, but underwent radial photometric changes due to the inside-out quenching that led to the systematic decrease of ∇Υ⋆ and to an increase of the light-weighted radius. The late reversing of ∇Υ⋆, t lb≈2 − 4 Gyr, roughly coincides with the global quenching of the CLE galaxies. We have pushed archaeological inferences to the limit, but thanks to the large number of objects and an understanding of how the caveats and assumptions affect our results, we conclude that they offer an average description of evolutionary behaviours of CLE progenitors that is valid at least qualitatively. [ABSTRACT FROM AUTHOR]

We investigate the formation of brightest cluster galaxies (BCGs) in the TNG300 cosmological simulation of the IllustrisTNG project. Our cluster sample consists of 700 haloes with |$M_{\rm 200}\ge 5 \times 10^{13} \, {\rm M}_{\odot }$| at z  = 0, along with their progenitors at earlier epochs. This includes 280 systems with |$M_{\rm 200}\ge 10^{14} \, {\rm M}_{\odot }$| at z  = 0, as well as three haloes with |$M_{\rm 200}\ge 10^{15} \, {\rm M}_{\odot }$|⁠. We find that the stellar masses and star formation rates of our simulated BCGs are in good agreement with observations at z ≲ 0.4, and that they have experienced, on average, ∼2 (∼3) major mergers since z  = 1 (z  = 2). Separating the BCG from the intracluster light (ICL) by means of a fixed 30 kpc aperture, we find that the fraction of stellar mass contributed by ex situ (i.e. accreted) stars at z  = 0 is approximately 70, 80, and 90 per cent for the BCG, BCG + ICL, and ICL, respectively. Tracking our simulated BCGs back in time using the merger trees, we find that they became dominated by ex situ stars at z ∼1–2, and that half of the stars that are part of the BCG at z  = 0 formed early (z ∼ 3) in other galaxies, but 'assembled' onto the BCG until later times (z ≈ 0.8 for the whole sample, z ≈ 0.5 for BCGs in |$M_{\rm 200}\ge 5 \times 10^{14} \, {\rm M}_{\odot }$| haloes). Finally, we show that the stellar mass profiles of BCGs are often dominated by ex situ stars at all radii, with stars from major mergers being found closer to the centre, while stars that were tidally stripped from other galaxies dominate the outer regions. [ABSTRACT FROM AUTHOR]

The stochastic order redshift technique (sort) is a simple, efficient, and robust method to improve cosmological redshift measurements. The method relies upon having a small (∼10 per cent) reference sample of high-quality redshifts. Within pencil-beam-like sub-volumes surrounding each galaxy, we use the precise d N /d z distribution of the reference sample to recover new redshifts and assign them one-to-one to galaxies such that the original rank order of redshifts is preserved. Preserving the rank order is motivated by the fact that random variables drawn from Gaussian probability density functions with different means but equal standard deviations satisfy stochastic ordering. This process is repeated for sub-volumes surrounding each galaxy in the survey. This results in every galaxy being assigned multiple 'recovered' redshifts from which a new redshift estimate is determined. An earlier paper applied sort to a mock Sloan Digital Sky Survey at z ≲ 0.2 and accurately recovered the two-point correlation function (2PCF) on scales ≳ 4  h −1Mpc. In this paper, we test the performance of sort in surveys spanning the redshift range 0.75 < z < 2.25. We used two mock surveys extracted from the Small MultiDark–Planck and Bolshoi–Planck N -body simulations with dark matter haloes that were populated by the Santa Cruz semi-analytic model. We find that sort overall improves redshift estimates, accurately recovers the redshift-space 2PCF ξ(s) on scales ≳ 2.5  h −1Mpc, and provides improved local density estimates in regions of average or higher density, which may allow for improved understanding of how galaxy properties relate to their environments. [ABSTRACT FROM AUTHOR]

We apply stellar population synthesis analysis to obtain spatially resolved archaeological inferences for a large sample of 'red and dead' Elliptical galaxies (Classical Ellipticals, CLEs) from the MaNGA/SDSS-IV DR15 survey. From their 2D stellar light and mass maps, we explore the differences between the radial mass and light distributions in the rest-frame bands g ,  r , and i as functions of look-back time, t lb, or redshift, z. We characterize these differences through the ratios between the following mass- and light-derived global properties: sizes, concentrations, and effective surface densities. We find that the mass-to-light ratios of these properties change with t lb, more the more massive the galaxies are. The CLE galaxy archaeological progenitors are, on average, less compact, concentrated, and dense in light than in mass as z decreases. However, at later times, when also the evolution of the progenitors becomes passive at all radii, there is an upturn in these trends and the differences between mass and light in compactness/concentration decrease towards z ∼ 0. The trends in the ratios of mass-to-light sizes agree qualitatively with results from direct observations in galaxy surveys at different redshifts. We discuss the caveats and interpretations of our results, and speculate that the strong structural evolution found in some previous studies for early-type galaxies could be explained partially by photometric changes rather than by intrinsic structural changes. [ABSTRACT FROM AUTHOR]

We characterize the conditional distributions of the H  i gas-to-stellar mass ratio, |$\mbox{$R_{\rm H\,\rm{i}}$}\equiv \mbox{$M_{\rm H\,\rm{i}}$}/\mbox{$M_{\ast }$}$|⁠ , given the stellar mass, M *, of local galaxies from M * ∼ 107–1012 M⊙ separated into centrals and satellites as well as into late- and early-type galaxies (LTGs and ETGs, respectively). To do so, we use (1) the homogeneous 'eXtended GALEX Arecibo SDSS Survey', xGASS (Catinella et al. 2018), by re-estimating their upper limits and taking into account them in our statistical analysis; and (2) the results from a large compilation of H  i data reported in Calette et al. (2018). We use the |$R_{\rm H\,\rm{i}}$| conditional distributions combined with the Galaxy Stellar Mass Function to infer the bivariate |$M_{\rm H\,\rm{i}}$| and M * distribution of all galaxies as well of the late/early-type and central/satellite subsamples and their combinations. Satellites are on average less H  i gas-rich than centrals at low and intermediate masses, with differences being larger for ETGs than LTGs; at M * > 3−5 × 1010 M⊙ the differences are negligible. The differences in the H  i gas content are much larger between LTGs and ETGs than between centrals and satellites. Our empirical H  i Mass Function is strongly dominated by central galaxies at all masses. The empirically constrained bivariate |$M_{\rm H\,\rm{i}}$| and M * distributions presented here can be used to compare and constrain theoretical predictions as well as to generate galaxy mock catalogues. [ABSTRACT FROM AUTHOR]

An analytical approach is proposed to study the evolution of the star-forming galaxy (SFG) main sequence (MS) and the fraction of dust-obscured star formation (SF) up to z ∼ 4. Far-ultraviolet (FUV) and infrared (IR) star formation rates (SFRs) are described as conditional probability functions of M*. We convolve them with the galaxy stellar mass function (GSMF) of SFGs to derive the FUV and IR luminosity functions (LFs). The two SF modes formalism is used to describe starburst galaxies. By fitting observed FUV and IR LFs, the parameterization of SFRFUV−M* and SFRIR− M* is constrained. Our derived SFRFUV+IR−M* reproduces the evolution of the MS as compared to other observational inferences. At any redshift, we find that the sSFRFUV+IR–M* relation for MS SFGs approaches a power law at the high-mass end. At lower masses, it bends, and eventually, the slope sign changes from negative to positive at very low masses. At z ∼ 0, this change of sign is at M* ∼ 5 × 108M⊙, close to the dust-obscured SF regime, M* ∼ 6 × 108M⊙. The slope sign change is related to the knee of the FUV LF. Our derived dust-obscured fractions agree with previous determinations at 0 ≤ z ≤ 2.5. Dust-obscured fractions depend strongly on mass with almost no dependence on redshift at z ≳ 1.2. At z ≲ 0.75, high-mass galaxies become more "transparent" compared to their high-redshift counterparts. On the other hand, low- and intermediate-mass galaxies have become more obscured by dust. The joint evolution of the GSMF and the FUV and IR LFs is a promising approach to study mass growth and dust formation/destruction mechanisms. [ABSTRACT FROM AUTHOR]

We use the stellar kinematics for 2458 galaxies from the MaNGA survey to explore a universal fundamental plane (UFP) described by the equation , defined by the logarithms of effective radius, Re; the surface brightness within Re, Ie; the dynamical mass-to-light ratio within Re, Ye; and the total velocity parameter at Re, , where is the rotation velocity and is the velocity dispersion. The surface brightness is within Re, Ie, and the dynamical mass-to-light ratio is within Re, ϒe. We use sophisticated Schwarzschild dynamical models for a subsample of 300 galaxies from the CALIFA survey to calibrate the universal fundamental plane. This calibration allows us to propose both (i) a parameterization to estimate the difficult-to-measure averaged dynamical mass-to-light ratio within Re, , once the internal kinematics, surface brightness, and effective radius are known; and (ii) a new, more robust dynamical mass proxy consistent with dynamical models within 0.09 dex. We reproduce the relation between the dynamical mass and the stellar mass in the inner regions of galaxies with lower scatter. We use the estimated from our analysis to explore the UFP with the MaNGA data set. We find that all galaxies, from spheroids to disks, follow the UFP with a scatter significantly smaller (0.05 dex) than the one reported for the fundamental plane (∼0.09 dex) and comparable with Tully–Fisher studies (∼0.05 dex), but for a wider range of galaxy types. We also confirm that spheroidal and spiral galaxies follow the same M⋆–S0.5 scaling relation, with lower scatter than the and ones, which is in agreement with previous studies found in the literature. [ABSTRACT FROM AUTHOR]

This paper is one in a series that explores the importance of radius as a second parameter in galaxy evolution. The topic investigated here is the relationship between star formation rate (SFR) and galaxy radius () for main-sequence star-forming galaxies. The key observational result is that, over a wide range of stellar mass and redshift in both CANDELS and SDSS, there is little correlation between SFR and at fixed stellar mass. The Kennicutt–Schmidt law, or any similar density-related star formation law, then implies that smaller galaxies must have lower gas fractions than larger galaxies (at fixed), and this is supported by observations of gas in local star-forming galaxies. We investigate the implications by adopting the equilibrium "bathtub" model: the ISM gas mass is assumed to be constant over time, and the net SFR is the difference between the accretion rate of gas onto the galaxy from the halo and the outflow rate due to winds. To match the observed null correlation between SFR and radius, the bathtub model requires that smaller galaxies at fixed mass have weaker galactic winds. Our hypothesis is that galaxies are a two-parameter family whose properties are set mainly by halo mass and concentration. These determine the radius and gas accretion rate, which in turn predict how wind strength needs to vary with to keep the SFR constant. [ABSTRACT FROM AUTHOR]

Existing models of galaxy formation have not yet explained striking correlations between structure and star formation activity in galaxies, notably the sloped and moving boundaries that divide star-forming from quenched galaxies in key structural diagrams. This paper uses these and other relations to "reverse engineer" the quenching process for central galaxies. The basic idea is that star-forming galaxies with larger radii (at a given stellar mass) have lower black hole (BH) masses due to lower central densities. Galaxies cross into the green valley when the cumulative effective energy radiated by their BH equals ∼4× their halo gas-binding energy. Because larger-radii galaxies have smaller BHs, one finds that they must evolve to higher stellar masses in order to meet this halo energy criterion, which explains the sloping boundaries. A possible cause of radii differences among star-forming galaxies is halo concentration. The evolutionary tracks of star-forming galaxies are nearly parallel to the green-valley boundaries, and it is mainly the sideways motions of these boundaries with cosmic time that cause galaxies to quench. BH scaling laws for star-forming, quenched, and green-valley galaxies are different, and most BH mass growth takes place in the green valley. Implications include the radii of star-forming galaxies are an important second parameter in shaping their BHs; BHs are connected to their halos but in different ways for star-forming, quenched, and green-valley galaxies; and the same BH–halo quenching mechanism has been in place since z ∼ 3. We conclude with a discussion of BH–galaxy coevolution and the origin and interpretation of BH scaling laws. [ABSTRACT FROM AUTHOR]

This paper studies pseudo-bulges (P-bulges) and classical bulges (C-bulges) in Sloan Digital Sky Survey (SDSS) central galaxies using the new bulge indicator ΔΣ1, which measures relative central stellar-mass surface density within 1 kpc. We compare ΔΣ1 to the established bulge-type indicator Δ〈μe〉 from Gadotti (2009) and show that classifying by ΔΣ1 agrees well with Δ〈μe〉. ΔΣ1 requires no bulge–disc decomposition and can be measured on SDSS images out to z  = 0.07. Bulge types using it are mapped on to 20 different structural and stellar-population properties for 12 000 SDSS central galaxies with masses 10.0 < log M */M⊙ < 10.4. New trends emerge from this large sample. Structural parameters show fairly linear log–log relations versus ΔΣ1 and Δ〈μe〉 with only moderate scatter, while stellar-population parameters show a highly non-linear 'elbow' in which specific star formation rate remains roughly flat with increasing central density and then falls rapidly at the elbow, where galaxies begin to quench. P-bulges occupy the low-density end of the horizontal arm of the elbow and are universally star forming, while C-bulges occupy the elbow and the vertical branch and exhibit a wide range of star formation rates at a fixed density. The non-linear relation between central density and star formation rate has been seen before, but this mapping on to bulge class is new. The wide range of star formation rates in C-bulges helps to explain why bulge classifications using different parameters have sometimes disagreed in the past. The elbow-shaped relation between density and stellar indices suggests that central structure and stellar populations evolve at different rates as galaxies begin to quench. [ABSTRACT FROM AUTHOR]

We study the global star formation rate (SFR) versus stellar mass (M *) correlation, and the spatially resolved SFR surface density (ΣSFR) versus stellar mass surface density (Σ*) correlation, in a sample of ∼2000 galaxies from the MaNGA MPL-5 survey. We classify galaxies and spatially resolved areas into star forming and retired according to their ionization processes. We confirm the existence of a star-forming main sequence (SFMS) for galaxies and spatially resolved areas, and show that they have the same nature, with the global as a consequence of the local one. The latter presents a bend below a limit Σ* value, ≈3 × 107 M |$\odot$|  kpc−2, which is not physical. Using only star-forming areas (SFAs) above this limit, a slope and a scatter of ≈1 and ≈0.27 dex are determined. The retired galaxies/areas strongly segregate from their respective SFMSs, by ∼−1.5 dex on average. We explore how the global/local SFMSs depend on galaxy morphology, finding that for star-forming galaxies and SFAs, there is a trend to lower values of star formation activity with earlier morphological types, which is more pronounced for the local SFMS. The morphology not only affects the global SFR due to the diminish of SFAs with earlier types, but also affects the local SF process. Our results suggest that the local SF at all radii is established by some universal mechanism partially modulated by morphology. Morphology seems to be connected to the slow aging and sharp decline of the SF process, and on its own it may depend on other properties as the environment. [ABSTRACT FROM AUTHOR]

We investigate the dependence of the galaxy–halo connection and galaxy density field in modified gravity models using the N -body simulations for f (R) and nDGP models at z  = 0. Because of the screening mechanisms employed by these models, chameleon and Vainshtein, haloes are clustered differently in the non-linear regime of structure formation. We quantify their deviations in the galaxy density field from the standard Λ cold dark matter (ΛCDM) model under different environments. We populate galaxies in haloes via the (sub)halo abundance matching. Our main results are as follows: (1) The galaxy–halo connection strongly depends on the gravity model; a maximum variation of |${\sim }40{{\ \rm per\ cent}}$| is observed between halo occupational distribution (HOD) parameters; (2) f (R) gravity models predict an excess of galaxies in low-density environments of |${\sim }10{{\ \rm per\ cent}}$| but predict a deficit of |${\sim }10{{\ \rm per\ cent}}$| at high-density environments for | f R 0| = 10−4 and 10−6 while | f R 0| = 10−5 predicts more high-density structures; nDGP models are consistent with ΛCDM; (3) different gravity models predict different dependences of the galaxy luminosity function (GLF) with the environment, especially in void-like regions we find differences around |${\sim }10{{\ \rm per\ cent}}$| for the f (R) models while nDPG models remain closer to ΛCDM for low-luminosity galaxies but there is a deficit of |${\sim }11{{\ \rm per\ cent}}$| for high-luminosity galaxies in all environments. We conclude that the dependence of the GLF with environment might provide a test to distinguish between gravity models and their screening mechanisms from the ΛCDM. We provide HOD parameters for the gravity models analysed in this paper. [ABSTRACT FROM AUTHOR]

By means of post-processed cosmological hydrodynamics simulations, we explore the ability of the fossil record method to recover the stellar mass, age gradients, and global/radial star formation and mass growth histories of galaxies observed with an optical Integral Field Unity (IFU). We use two simulations of representative Milky Way-sized galaxies, one disc-dominated and another bulge-dominated. We generate data cubes emulating MaNGA/SDSS-IV instrumental and observational conditions, and analyze them using the Pipe3D pipeline. For optimal MaNGA instrumental/observational set-ups, the global masses, ages, and dust extinctions of both galaxies are well recovered within the uncertainties, while for the radial distributions, the trend is to get slightly flatter age gradients and weaker inside-out growth modes than the true ones. The main bias is in recovering younger stellar populations in the inner, older regions, and slightly older stellar populations in the outer, younger regions, as well as lower global stellar masses. These trends are enhanced as lower is the spatial sampling/resolution (less number of fibres), more inclined and dust-attenuated is the observed galaxy, lower is the signal-to-noise ratio, and worse is the seeing. The recovered properties and histories are more affected for the disc-dominated galaxy with a prominent inside-out growth mode than for the bulge-dominated galaxy assembled earlier and more coherently. We make publicly available the code and the mock IFU datacubes used in this paper. [ABSTRACT FROM AUTHOR]

We present the results of the archaeological analysis of the stellar populations of a sample of ∼4000 galaxies observed by the SDSS-IV MaNGA survey using pipe3d. Based on this analysis we extract a sample of ∼150 000 star formation rates (SFRs) and stellar masses that mimic a single cosmological survey covering the redshift range between |$z$| ∼ 0 and |$z$| ∼ 7. We confirm that the star-forming main sequence holds as a tight relation in this range of redshifts, evolving in both the zero-point and slope. This evolution is different for local star-forming (SFGs) and retired (RGs) galaxies, with the latter presenting a stronger evolution in the zero-point and a weaker evolution in the slope. The fraction of RGs decreases rapidly with |$z$|⁠, particularly for RGs at |$z$| ∼ 0. We detect RGs well above |$z$| > 1, although not all of them are progenitors of local RGs. Finally, adopting the required corrections to make the survey complete in mass in a limited volume, we recover the cosmic SFR, stellar-mass density, and average specific SFR histories of the Universe in this wide range of look-back times. Our derivations agree with those reported by various cosmological surveys. We demonstrate that the progenitors of local RGs were more actively forming stars in the past, contributing to most of the cosmic SFR density at |$z$| > 0.5, and to most of the cosmic stellar-mass density at any redshift. They suffer a general quenching in the SFR at z ∼  0.35. Below this redshift the progenitors of local SFGs dominate the SFR density of the Universe. [ABSTRACT FROM AUTHOR]

We study the properties of distinct dark matter haloes (i.e. those that are not subhaloes) that have a final virial mass |$\rm{M_{\rm vir}}$| at |$z$| = 0 less than their peak mass (⁠|$\rm{M_{\rm peak}}$|⁠) in the Bolshoi–Planck cosmological simulation. We identify two primary causes of halo mass-loss: relaxation after a major merger and tidal stripping by a massive neighbouring halo. Major mergers initially boost |$\rm{M_{\rm vir}}$| and typically cause the final halo to become more prolate and less relaxed and to have higher spin and lower NFW concentration. As the halo relaxes, high-energy material from the recent merger gradually escapes beyond the virial radius, temporarily resulting in a net negative accretion rate that reduces the halo mass by |$5{\hbox{-}}15{{\ \rm per\ cent}}$| on average. Haloes that experience a major merger around |$z$| = 0.4 typically reach a minimum mass near |$z$| = 0. Tidal stripping mainly occurs in dense regions, and it causes haloes to become less prolate and have lower spins and higher NFW concentrations. Tidally stripped haloes often lose a large fraction of their peak mass (⁠|${\gt}20{{\ \rm per\ cent}}$|⁠) and most never recover (or even re-attain a positive accretion rate). Low-mass haloes can be strongly affected by both post-merger mass-loss and tidal stripping, while high-mass haloes are predominantly influenced by post-merger mass-loss and show few signs of significant tidal stripping. [ABSTRACT FROM AUTHOR]

We used ionized gas and stellar kinematics for 667 spatially resolved galaxies publicly available from the Calar Alto Legacy Integral Field Area survey (CALIFA) third Data Release with the aim of studying kinematic scaling relations as the Tully & Fisher (TF) relation using rotation velocity, Vrot, the Faber & Jackson (FJ) relation using velocity dispersion, σ, and also a combination of Vrot and σ through the SK parameter defined as $S_{K}^2 = KV_{rot}^2 + \sigma ^2$ with constant K. Late-type and early-type galaxies reproduce the TF and FJ relations. Some early-type galaxies also follow the TF relation and some late-type galaxies the FJ relation, but always with larger scatter. On the contrary, when we use the SK parameter, all galaxies, regardless of the morphological type, lie on the same scaling relation, showing a tight correlation with the total stellar mass, M⋆. Indeed, we find that the scatter in this relation is smaller or equal to that of the TF and FJ relations. We explore different values of the K parameter without significant differences (slope and scatter) in our final results with respect to the case K= 0.5 besides a small change in the zero-point. We calibrate the kinematic $S_{K}^2$ dynamical mass proxy in order to make it consistent with sophisticated published dynamical models within 0.15 dex. We show that the SK proxy is able to reproduce the relation between the dynamical mass and the stellar mass in the inner regions of galaxies. Our result may be useful in order to produce fast estimations of the central dynamical mass in galaxies and to study correlations in large galaxy surveys. [ABSTRACT FROM AUTHOR]

(Sub)halo abundance matching (SHAM) assumes that one (sub) halo property, such as mass Mvir or peak circular velocity Vpeak, determines properties of the galaxy hosted in each (sub) halo such as its luminosity or stellar mass. This assumption implies that the dependence of galaxy luminosity functions (GLFs) and the galaxy stellar mass function (GSMF) on environmental density is determined by the corresponding halo density dependence. In this paper, we test this by determining from a Sloan Digital Sky Survey sample the observed dependence with environmental density of the ugriz GLFs and GSMF for all galaxies, and for central and satellite galaxies separately. We then show that the SHAM predictions are in remarkable agreement with these observations, even when the galaxy population is divided between central and satellite galaxies. However, we show that SHAM fails to reproduce the correct dependence between environmental density and g - r colour for all galaxies and central galaxies, although it better reproduces the colour dependence on environmental density of satellite galaxies. [ABSTRACT FROM AUTHOR]

We present a simple, efficient and robust approach to improve cosmological redshift measurements. The method is based on the presence of a reference sample for which a precise redshift number distribution (dN/dz) can be obtained for different pencil-beam-like sub-volumes within the original survey. For each sub-volume we then impose that: (i) the redshift number distribution of the uncertain redshift measurements matches the reference dN/dz corrected by their selection functions and (ii) the rank order in redshift of the original ensemble of uncertain measurements is preserved. The latter step is motivated by the fact that random variables drawn from Gaussian probability density functions (PDFs) of different means and arbitrarily large standard deviations satisfy stochastic ordering. We then repeat this simple algorithm for multiple arbitrary pencil-beam-like overlapping sub-volumes; in this manner, each uncertain measurement has multiple (non-independent) 'recovered' redshifts which can be used to estimate a new redshift PDF. We refer to this method as the Stochastic Order Redshift Technique (SORT). We have used a state-of-the-art N-body simulation to test the performance of SORT under simple assumptions and found that it can improve the quality of cosmological redshifts in a robust and efficient manner. Particularly, SORT redshifts (zsort) are able to recover the distinctive features of the so-called 'cosmic web' and can provide unbiased measurement of the two-point correlation function on scales ≳4 h-1Mpc. Given its simplicity, we envision that a method like SORT can be incorporated into more sophisticated algorithms aimed to exploit the full potential of large extragalactic photometric surveys. [ABSTRACT FROM AUTHOR]

We present new determinations of the stellar-to-halo mass relation (SHMR) at z = 0-10 that match the evolution of the galaxy stellar mass function, the star formation rate (SFR)-M* relation and the cosmic SFR. We utilize a compilation of 40 observational studies from the literature and correct them for potential biases. Using our robust determinations of halo mass assembly and the SHMR, we infer star formation histories, merger rates and structural properties for average galaxies, combining star-forming and quenched galaxies. Our main findings are as follows: (1) The halo mass M50 above which 50 per cent of galaxies are quenched coincides with sSFR/sMAR ~ 1, where sSFR is the specific SFR and sMAR is the specific halo mass accretion rate. (2) M50 increases with redshift, presumably due to cold streams being more efficient at high redshifts, while virial shocks and active galactic nucleus feedback become more relevant at lower redshifts. (3) The ratio sSFR/sMAR has a peak value, which occurs around Mvir ~ 2 × 1011 M⊙. (4) The stellar mass density within 1 kpc, Σ1, is a good indicator of the galactic global sSFR. (5) Galaxies are statistically quenched after they reach a maximum in Σ1, consistent with theoretical expectations of the gas compaction model; this maximum depends on redshift. (6) In-situ star formation is responsible for most galactic stellar mass growth, especially for lower mass galaxies. (7) Galaxies grow inside-out. The marked change in the slope of the size-mass relation when galaxies became quenched, from d log Reff/d logM* ~ 0.35 to ~2.5, could be the result of dry minor mergers. [ABSTRACT FROM AUTHOR]

Climate variability and change can have important impacts for crop production. Therefore, the aim of this study is to investigate projections of the wheat yield in an increasingly warm climate. To address our objectives, we determined relationships between wheat yield in Spain and large-scale variables. Partial least squares regression was applied to determine the modes of the climate variables that drive wheat-yield variability, revealing a significant influence of surface solar radiation. Based on seasonal patterns of solar radiation, we determine models to estimate inter-annual wheat-yield variability. We find that the performance of the models based on solar radiation is better than that of earlier studies based on temperatures and precipitation variables. In this way, we use simulations of the Coupled Model Intercomparison Project Phase 5 (CMIP5) to project wheat-yield trend under warming climate by implementing direct statistical downscaling. The expected range of projected wheat yield trend for 21st century indicates decreases of about 6-8% across Spain. The suggested models could be applied for adaptation and planning. [ABSTRACT FROM AUTHOR]

ABSTRACT Climate variability and change can have important impacts for crop production. Therefore, the aim of this study is to investigate projections of the wheat yield in an increasingly warm climate. To address our objectives, we determined relationships between wheat yield in Spain and large-scale variables. Partial least squares regression was applied to determine the modes of the climate variables that drive wheat-yield variability, revealing a significant influence of surface solar radiation. Based on seasonal patterns of solar radiation, we determine models to estimate inter-annual wheat-yield variability. We find that the performance of the models based on solar radiation is better than that of earlier studies based on temperatures and precipitation variables. In this way, we use simulations of the Coupled Model Intercomparison Project Phase 5 ( CMIP5) to project wheat-yield trend under warming climate by implementing direct statistical downscaling. The expected range of projected wheat yield trend for 21st century indicates decreases of about 6-8% across Spain. The suggested models could be applied for adaptation and planning. [ABSTRACT FROM AUTHOR]

We report and provide fitting functions for the abundance of dark matter halos and subhalos as a function of mass, circular velocity, and redshift from the new Bolshoi-Planck and MultiDark-Planck ΛCDM cosmological simulations, based on the Planck cosmological parameters. We also report the halo mass accretion rates, which may be connected with galaxy star formation rates. We show that the higher cosmological matter density of the Planck parameters compared with the WMAP parameters leads to higher abundance of massive halos at high redshifts. We find that the median halo spin parameter λB=J(√2MvirRvirVvir)−1 is nearly independent of redshift, leading to predicted evolution of galaxy sizes that is consistent with observations, while the significant decrease with redshift in median λP=J|E|−1/2G−1M−5/2 predicts more decrease in galaxy sizes than is observed. Using the Tully-Fisher and Faber-Jackson relations between galaxy velocity and mass, we show that a simple model of how galaxy velocity is related to halo maximum circular velocity leads to increasing overprediction of cosmic stellar mass density as redshift increases beyond redshifts z∼1, implying that such velocity-mass relations must change at redshifts z ≳ 1. By making a realistic model of how observed galaxy velocities are related to halo circular velocity, we show that recent optical and radio observations of the abundance of galaxies are in good agreement with our ΛCDM simulations. Our halo demographics are based on updated versions of the \rockstar\ and \ctrees\ codes, and this paper includes appendices explaining all of their outputs. This paper is an introduction to a series of related papers presenting other analyses of the Bolshoi-Planck and MultiDark-Planck simulations. [ABSTRACT FROM AUTHOR]

The galaxy stellar-to-halo mass relation (SHMR) is nearly time-independent for z < 4. We therefore construct a time-independent SHMR model for central galaxies, wherein the in situ star formation rate (SFR) is determined by the halo mass accretion rate (MAR), which we call stellar halo accretion rate coevolution (SHARC). We show that the ∼0.3 dex dispersion of the halo MAR matches the observed dispersion of the SFR on the star formation main sequence (MS). In the context of 'bathtub'-type models of galaxy formation, SHARC leads to mass-dependent constraints on the relation between SFR and MAR. Despite its simplicity and the simplified treatment of mass growth from mergers, the SHARC model is likely to be a good approximation for central galaxies with M* = 109-1010.5M☉ that are on the MS, representing most of the star formation in the Universe. SHARC predictions agree with observed SFRs for galaxies on the MS at low redshifts, agree fairly well at z ∼ 4, but exceed observations at z ≳ 4. Assuming that the interstellar gas mass is constant for each galaxy (the 'equilibrium condition' in bathtub models), the SHARC model allows calculation of net mass loading factors for inflowing and outflowing gas.With assumptions about preventive feedback based on simulations, SHARC allows calculation of galaxy metallicity evolution. If galaxy SFRs indeed track halo MARs, especially at low redshifts, that may help explain the success of models linking galaxy properties to haloes (including age-matching) and the similarities between two-halo galaxy conformity and halo mass accretion conformity. [ABSTRACT FROM AUTHOR]

We use a sample of ≈6000 galaxies detected by the Arecibo Legacy Fast ALFA (ALFALFA) 21 cm survey to measure the clustering properties of H I-selected galaxies. We find no convincing evidence for a dependence of clustering on galactic atomic hydrogen (H I) mass, over the range MH I ≈ 108.5-1010.5M☼. We show that previously reported results of weaker clustering for low H I mass galaxies are probably due to finite-volume effects. In addition, we compare the clustering of ALFALFA galaxies with optically selected samples drawn from the Sloan Digital Sky Survey (SDSS). We find that H I-selected galaxies cluster more weakly than even relatively optically faint galaxies, when no color selection is applied. Conversely, when SDSS galaxies are split based on their color, we find that the correlation function of blue optical galaxies is practically indistinguishable from that of H I-selected galaxies. At the same time, SDSS galaxies with red colors are found to cluster significantly more than H I-selected galaxies, a fact that is evident in both the projected as well as the full two-dimensional correlation function. A cross-correlation analysis further reveals that gas-rich galaxies “avoid” being located within ≈3 Mpc of optical galaxies with red colors. Next, we consider the clustering properties of halo samples selected from the Bolshoi ΛCDM simulation. A comparison with the clustering of ALFALFA galaxies suggests that galactic H I mass is not tightly related to host halo mass and that a sizable fraction of subhalos do not host H I galaxies. Lastly, we find that we can recover fairly well the correlation function of H I galaxies by just excluding halos with low spin parameter. This finding lends support to the hypothesis that halo spin plays a key role in determining the gas content of galaxies. [ABSTRACT FROM AUTHOR]

A growing interest in extreme precipitation has spread through the scientific community due to the effects of global climate change on the hydrological cycle and their threat on natural systems more than averaged climatic values. Understanding the variability of hydrological indices and their association to atmospheric processes could help to project the frequency and severity of extremes. This paper evaluates the trend of three precipitation extremes: the number of consecutive dry/wet days (CDD/CWD) and the quotient of the precipitation in days where daily precipitation exceeds the 95th percentile of the reference period and the total amount of precipitation (or contribution of very wet days, R95pTOT). The aim of this study is twofold. First, extreme indicators are compared against accumulated precipitation (RR) over Europe in terms of trends using non-parametric approaches. Second, we analyse the geographic opposite trends found over different parts of Europe by considering their relationships with large-scale processes, using different teleconnection patterns. The study is accomplished for the four seasons using the gridded E-OBS dataset developed within the EU ENSEMBLES project. Different patterns of variability were found for CWD and CDD in winter and summer, with north-south and east-west configurations, respectively. We consider physical factors to understand the extremes variability by linking large-scale processes and hydrological extremes. Opposite association with the North Atlantic Oscillation in winter and summer, and the relationships with the Scandinavian, East Atlantic patterns and El Niño/Southern Oscillation events in spring and autumn gave insight into the trend differences. Significant relationships were found between the Atlantic Multidecadal Oscillation and very extreme precipitation (R95pTOT) during the whole year. The largest extreme anomalies were analysed by composite maps using atmospheric variables and sea surface temperature. The association of extreme precipitation indices and large-scale variables found in this work could pave the way of new possibilities for the projection of extremes in downscaling techniques. [ABSTRACT FROM AUTHOR]

Several occupational distributions for satellite galaxies more massive than m∗ ≈ 4 × 107 M⊙ around Milky-Way (MW)-sized hosts are presented and used to predict the internal dynamics of these satellites as a function of m∗. For the analysis, a large galaxy group mock catalog is constructed on the basis of (sub)halo-to-stellarmass relations fully constrained with currently available observations, namely the galaxy stellarmass function decomposed into centrals and satellites, and the two-point correlation functions at different masses. We find that 6.6% of MW-sized galaxies host two satellites in the mass range of the Small and Large Magellanic Clouds (SMC and LMC, respectively). The probabilities of the MW-sized galaxies having one satellite equal to or larger than the LMC, two satellites equal to or larger than the SMC, or three satellites equal to or larger than Sagittarius (Sgr) are ≈0.26, 0.14, and 0.14, respectively. The cumulative satellite mass function of the MW, Ns (⩾m∗), down to the mass of the Fornax dwarf is within the 1σ distribution of all the MW-sized galaxies. We find that MW-sized hosts with three satellites more massive than Sgr (as the MW) are among the most common cases. However, the most and second most massive satellites in these systems are smaller than the LMC and SMC by roughly 0.7 and 0.8 dex, respectively. We conclude that the distribution Ns (⩾m∗) for MW-sized galaxies is quite broad, the particular case of the MW being of low frequency but not an outlier. The halo mass of MW-sized galaxies correlates only weakly with Ns (⩾m∗). Then, it is not possible to accurately determine the MW halo mass by means of its Ns (⩾m∗); from our catalog, we constrain a lower limit of 1.38 × 1012M⊙ at the 1σ level. Our analysis strongly suggests that the abundance of massive subhalos should agree with the abundance of massive satellites in all MW-sized hosts, i.e., there is not a missing (massive) satellite problem for the ΛCDM cosmology. However, we confirm that the maximum circular velocity, vmax, of the subhalos of satellites smaller than m∗ ∼ 108M⊙ is systematically larger than the vmax inferred from current observational studies of the MW bright dwarf satellites; different from previous works, this conclusion is based on an analysis of the overall population of MW-sized galaxies. Some pieces of evidence suggest that the issue could refer only to satellite dwarfs but not to central dwarfs, then environmental processes associated with dwarfs inside host halos combined with supernova-driven core expansion should be on the basis of the lowering of vmax. [ABSTRACT FROM AUTHOR]

We infer the local stellar-to-halo/subhalo mass relations (MRs) for central and satellite galaxies separately. Our statistical method is an extension of the abundance matching, halo occupation distribution, and conditional stellar mass function formalisms. We constrain the model using several combinations of observational data, consisting of the total galaxy stellar mass function (GSMF), its decomposition into centrals and satellites, and the projected twopoint correlation functions (2PCFs)measured in different stellarmass (M☉) bins. In addition, we use the ⋀CDMhalo and subhalo mass functions. The differences among the resultingMRs are within the model-fit uncertainties (which are very small, smaller than the intrinsic scatter between galaxy and halo mass), no matter what combination of data are used. This shows that matching abundances or occupational numbers is equivalent, and that the GSMFs and 2PCFs are tightly connected. We also constrain the values of the intrinsic scatter around the central-halo (CH) and satellite-subhalo (SS) MRs assuming them to be constant: σc = 0.168 ± 0.051 dex and σs = 0.172 ± 0.057 dex, respectively. The CH and SS MRs are actually different, in particular when we take the subhalo mass at the present-day epoch instead of at their accretion time. When using the MRs for studying the satellite population (e.g., in the Milky Way,MW), the SS MR should be chosen instead of the average one. Our model allows one to calculate several population statistics. We find that the central galaxy M☉ is not on average within the mass distribution of the most massive satellite, even for cluster-sized halos, i.e., centrals are not a mere realization of the high end of the satellite mass function; however for >3 × 1013M" halos, ~15% of centrals could be. We also find that the probabilities of MW-sized halos of having N Magellanic Cloud (MC) sized satellites agree well with observational measures; for a halo mass of 2×1012M", the probability to have two MCs is 5.4%, but if we exclude those systems with satellites larger than the MCs, then the probability decreases to <2.2%. [ABSTRACT FROM AUTHOR]

The article presents a comparison of the trends of precipitation over Iberian Peninsula and North Atlantic Oscillation (NAO) under climate change conditions utilizing the Coupled Model Intercomparison Project phase 3. The evaluation is performed in two multi-models such as the climate in the 20th century and the 21st century. Result shows that the simulation in the 20th century underestimate the trend both in the NAO and precipitation and in the 21st century indicates a change in NAO.

The aims of this study are to identify the trend of warm days and cold nights over the Iberian Peninsula and to connect the variations with large-scale variables. The reasons for performing this analysis are the effects that extremes events have on different ecosystems. Here, we present the results on spatial and temporal variability of warm days (TX90), or those exceeding the 90th percentile of maximum temperature, and cold nights (TN10), or those falling below the 10th percentile of minimum temperature. The extreme indices were derived from daily observations at stations and gridded data over land area for the period 1950 to 2006. Significant trends of more warm days and fewer cold nights were found. The trend to fewer cold nights is within the interval of global results given by the IPCC AR4 report; however, the trend to warm days is greater than the corresponding global trend. The influence of large-scale variables on these extreme indices was examined by means of the Empirical Orthogonal Function, correlation, composite maps and multiple regression analyses. Changes in TX90 are connected with the Scandinavian teleconnection index and a preferred mode of geopotential height at 500 hPa over the North Atlantic. Changes in TN10 are connected with the East Atlantic teleconnection index and the leading mode of Sea Surface Temperature (SST) variability over the North Atlantic area. Based on the links between the extreme indices and the large-scale variables we derived statistical models to describe the response of TX90 and TN10 to atmospheric circulation and SST variations. The models characterized the observed variations of TX90 and TN10 reasonably well. The results of this study encourage us to analyze, in further work, how temperature extremes might change over the Iberian Peninsula under warmer climate conditions. [ABSTRACT FROM AUTHOR]

An increasing amount of recent observational evidence shows that the less massive galaxies are, the higher on average their specific star-formation rates (SSFR = , where is the stellar mass). Such a trend, called the ‘SSFR downsizing’ (SSFR–DS) phenomenon, is seen for local and high-redshift (back to ) galaxy samples. We use observational data related only to disc galaxies and explore how the average SSFR changes with z for different masses. For all masses in the range , the SSFR increases with to a power that seems not to depend on , and at all redshifts smaller galaxies always have higher SSFRs; galaxies less massive than are now forming stars at a greater rate than in the past, assuming constant SFRs over a Hubble time to build stellar mass. We show that these features strongly disagree with the Λ Cold Dark Matter (ΛCDM) halo hierarchical mass accretion rates. Further, by means of self-consistent models of disc galaxy evolution inside growing ΛCDM haloes, the effects of disc-feedback-driven outflows and gas re-accretion on galaxy SSFR histories are explored. The parameters of the outflow and re-accretion schemes are tuned to reproduce the present-day relation (where Mh is the halo mass) inferred from the observationally based function of disc galaxies. In the case of outflows only, the SSFR of individual model galaxies increases with z roughly as ( for all masses (somewhat shallower than observations) with a normalization factor that depends on mass as , i.e more massive galaxies have slightly larger SSFRs, contrary to the observed strong SSFR–DS trend. For the re-accretion cases, the dependence on z remains approximately the same as without gas re-infall, but the correlation with mass increases even for the most reasonable values of the model parameters. The comparison of models and observations in the SSFR– plane at (where the data are more reliable) clearly shows the divergent trend in SSFR when the masses are lower (upsizing versus downsizing). We explain why our models show the reported trends, and conclude that the SSFR–DS phenomenon for low-mass galaxies poses a sharp challenge for ΛCDM-based disc galaxy evolution models. [ABSTRACT FROM AUTHOR]

In this paper, the ability of model outputs from the Intergovernmental Panel on Climate Change (IPCC) to describe the natural internal variability of precipitation observations is evaluated. The analysis is focused on the Iberian Peninsula for December–February (DJF). The study was performed with observed data from National Meteorological Institutes, reanalysis data from the National Centers for Environmental Prediction–National Center for Atmospheric Research, teleconnection indices, and model simulations. First, the seasonal cycle, mean winter pattern, and tendency for nine model simulations were evaluated. Then, four models were selected to obtain interannual variability and to diagnose the links between precipitation and large-scale circulation. This intercomparison is based on the modes obtained by the empirical orthogonal function (EOF) and spectral analyses to investigate the temporal properties of the most significant spatial patterns. The models well reproduce the observed seasonal cycle and the mean winter pattern; however, they poorly capture the interannual variability found in observed data. To ascertain the reasons for these results, features affecting the precipitation process are considered by analyzing the relationships with the dominant modes of large-scale atmospheric fields, such as sea level pressure, storm activity, jet stream, moisture flux, and teleconnection indices. The precipitation response to the mean flow suggests signs of potential seasonal predictability in DJF. [ABSTRACT FROM AUTHOR]

The multi-model ensemble for seasonal to interannual prediction developed in the European Union project DEMETER has been used to quantify the predictability of monthly average maximum temperature that could be achieved operationally over the Iberian Peninsula. Statistical downscaling based on canonical correlation analysis is applied to increase the spatial resolution available from the global models. The downscaling is based on empirical connections between the North Atlantic sea level pressure and monthly average maximum temperature over the Iberian Peninsula.The maximum temperature estimated from the multi-model ensemble and the single models is compared to the observations. The statistical downscaling model skill is characterized by means of the correlation, variance fraction and the Brier skill score. The results suggest the following: the downscaling model works properly when driven by observed large-scale fields in terms of the correlation and the variance fraction scores, despite some problems owing to sample degeneracy; the predictability is almost limited to February, which is one of the initialization months of the DEMETER ensemble, and it is lost when this month is not considered as starting month. This result is supported by the fact that the areally averaged reproducibility is lower during non-initialization months. In any case, the analysis of the variance test performed reveals that the monthly average maximum temperature is scarcely predictable. Finally, the results also support the advantage of using a multi-model ensemble approach instead of single models participating in DEMETER. [ABSTRACT FROM AUTHOR]

The main questions motivating this study are: Can climate simulations describe the observations? To what extent can we use climate models to predict climate change? For this purpose, an analysis was made of the correspondences and/or discrepancies between observed winter precipitation data and the data from the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) reanalysis project, and from two global climatic models: ECHAM4/OPYC3 and HadCM3. The data used correspond to the accumulated winter precipitation for the period 1949–2000, and comparisons of the mean and variability patterns were made. The methods used were principal components analysis, to break down variability and reduce the dimensions of the fields, and correlation and cross-spectrum analyses for comparison of the time series. For all these, we studied the suitability of their average distributions, as well as their modes of spatial and spectral variability. The results for the Iberian Peninsula show good agreement between the precipitation data of the NCEP–NCAR reanalysis and the observations, both in the average analysis and in the main modes of spatial and time variability. Therefore, the reanalysis data were proved to be a good resource for interpreting climate variations. As regards the climatic models considered, in general the results point to their suitability for describing the spatial distribution of winter precipitation, whereas the spectral association is less appropriate. The variability of the precipitation data was related to circulation patterns and teleconnection indices, such as the North Atlantic oscillation and the Arctic oscillation. The results allow us to conclude that the discrepancies between the two models and observations must be due to a weak representation of the interannual variability. Copyright © 2004 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Observational series of winter precipitation in the eastern part of the Cantabrian coast in the northern Iberian Peninsula are studied. This rather small area shows a clearly different interannual variability to the rest of the Peninsula. Series of winter precipitation for the whole area are defined using principal component (PC) analysis and they reflect the variability that can be attributed to changes in atmospheric circulation around the area. This variability is physically explained on the basis of the structure of baroclinic activity and vertically integrated moisture transports over the area derived from the NCEP/NCAR Reanalysis project. According to them, the leading PC of winter precipitation represents the overall precipitation over the area. Wet phases of this PC are associated to an increase of baroclinic activity leaving the eastern part of the Atlantic storm track and entering the Mediterranean basin. Conversely, dry phases show a strong reduction of baroclinic activity over the region. The second PC is linked to meridional water vapour transports over the area, which are affected by the topography of the region. Copyright © 2001 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

This is the first in a series of papers examining the demographics of star-forming (SF) galaxies at 0.2 < z < 2.5 in CANDELS. We study 9100 galaxies from GOODS-S and UDS, having published values of redshifts, masses, star formation rates (SFRs), and dust attenuation (AV) derived from UV–optical spectral energy distribution fitting. In agreement with previous works, we find that the UVJ colors of a galaxy are closely correlated with its specific star formation rate (SSFR) and AV. We define rotated UVJ coordinate axes, termed SSED and CSED, that are parallel and perpendicular to the SF sequence and derive a quantitative calibration that predicts SSFR from CSED with an accuracy of ∼0.2 dex. SFRs from UV–optical fitting and from UV+IR values based on Spitzer/MIPS 24 μm agree well overall, but systematic differences of order 0.2 dex exist at high and low redshifts. A novel plotting scheme conveys the evolution of multiple galaxy properties simultaneously, and dust growth, as well as star formation decline and quenching, exhibit “mass-accelerated evolution” (“downsizing”). A population of transition galaxies below the SF main sequence is identified. These objects are located between SF and quiescent galaxies in UVJ space, and have lower AV and smaller radii than galaxies on the main sequence. Their properties are consistent with their being in transit between the two regions. The relative numbers of quenched, transition, and SF galaxies are given as a function of mass and redshift. [ABSTRACT FROM AUTHOR]

We study the global and radial stellar mass assembly of eight zoomed-in Milky Way (MW)-sized galaxies produced in hydrodynamics cosmological simulations. The disk-dominated galaxies (four) show a fast initial stellar mass growth in the innermost parts, driven mostly by in situ star formation (SF), but since z ∼ 2−1, the SF has entered a long-term quenching phase. The outer regions follow this trend but more gently, as they are more external. As a result, the radial stellar mass growth is highly inside-out due to both inside-out structural growth and inside-out SF quenching. The half-mass radius evolves fast; for instance, (z = 1) < 0.5 (z = 0). Two other runs resemble lenticular galaxies. One also shows a pronounced inside-out growth, and the other one presents a nearly uniform radial mass assembly. The other two galaxies suffered late major mergers. Their normalized radial mass growth histories (MGHs) are very close, but with periods of outside-in assembly during or after the mergers. For all of the simulations, the archaeological radial MGHs calculated from the z = 0 stellar particle age distribution are similar to current MGHs, which shows that the mass assembly by ex situ stars and the radial mass transport do not significantly change their radial mass distributions. Our results agree qualitatively with observational inferences from the fossil record method applied to a survey of local galaxies and from look-back observations of progenitors of MW-sized galaxies. However, the inside-out growth mode is more pronounced, and the growth is faster in simulations than in observational inferences. [ABSTRACT FROM AUTHOR]

By means of a statistical approach that combines different semi-empirical methods of galaxy-halo connection, we derive the stellar-to-halo mass relations (SHMR) of local blue and red central galaxies. We also constrain the fraction of halos hosting blue/red central galaxies and the occupation statistics of blue and red satellites as a function of halo mass, Mh. For the observational input we use the blue and red central/satellite galaxy stellar mass functions and two-point correlation functions in the stellar mass range of 9 < log(M*/M☼) <12. We find that: (1) the SHMR of central galaxies is segregated by color, with blue centrals having a SHMR above that of red centrals; at log(Mh/M☼) ∼12, the M*-to-Mh ratio of the blue centrals is ≈0.05, which is ∼1.7 times larger than the value of red centrals. (2) The constrained scatters around the SHMRs of red and blue centrals are ≈0.14 and ≈0.11 dex, respectively. The scatter of the average SHMR of all central galaxies changes from ∼0.20 dex to ∼0.14 dex in the 11.3 < log(Mh/M☼) <15 range. (3) The fraction of halos hosting blue centrals at M☼ is 87%, but at 2 × 1012M☼ decays to ∼20%, approaching a few percent at higher masses. The characteristic mass at which this fraction is the same for blue and red galaxies is M☼. Our results suggest that the SHMR of central galaxies at large masses is shaped by mass quenching. At low masses processes that delay star formation without invoking too strong supernova-driven outflows could explain the high M*-to-Mh ratios of blue centrals as compared to those of the scarce red centrals. [ABSTRACT FROM AUTHOR]

We perform an exhaustive comparison among central galaxies from Sloan Digital Sky Survey catalogs in different local environments at 0.01 ⩽ z ⩽ 0.08. The central galaxies are separated into two categories: group centrals (host halos containing satellites) and field centrals (host halos without satellites). From the latter, we select two subsamples: isolated centrals and bright field centrals, both with the same magnitude limit. The stellar mass (Ms) distributions of the field and group central galaxies are different, which explains why in general the field central galaxies are mainly located in the blue cloud/star-forming regions, whereas the group central galaxies are strongly biased to the red sequence/passive regions. The isolated centrals occupy the same regions as the bright field centrals since both populations have similar Ms distributions. At parity of Ms, the color and specific star formation rate (sSFR) distributions of the samples are similar, especially between field and group centrals. Furthermore, we find that the stellar-to-halo mass (Ms-Mh) relation of isolated galaxies does not depend on the color, sSFR, and morphological type. For systems without satellites, the Ms-Mh relation steepens at high halo masses compared to group centrals, which is a consequence of assuming a one-to-one relation between group total stellar mass and halo mass. Under the same assumption, the scatter around the Ms-Mh relation of centrals with satellites increases with halo mass. Our results suggest that the mass growth of central galaxies is mostly driven by the halo mass, with environment and mergers playing a secondary role. [ABSTRACT FROM AUTHOR]

We present zoom-in N-body/hydrodynamics resimulations of dwarf galaxies formed in isolated cold dark matter (CDM) halos with the same virial mass (Mv ≈ 2.5 × 1010M☼) at redshift z = 0. Our goals are to (1) study the mass assembly histories (MAHs) of the halo, stellar, and gaseous components; and (2) explore the effects of the halo MAHs on the stellar/baryonic assembly of simulated dwarfs. Overall, the dwarfs are roughly consistent with observations. More specific results include: (1) the stellar-to-halo mass ratio remains roughly constant since z ∼ 1, i.e., the stellar MAHs closely follow halo MAHs. (2) The evolution of the galaxy gas fractions, fg, are episodic, showing that the supernova-driven outflows play an important role in regulating fg—and hence, the star formation rate (SFR)—however, in most cases, a large fraction of the gas is ejected from the halo. (3) The star formation histories are episodic with changes in the SFRs, measured every 100 Myr, of factors of 2-10 on average. (4) Although the dwarfs formed in late assembled halos show more extended SF histories, their z = 0 specific SFRs are still below observations. (5) The inclusion of baryons most of the time reduces the virial mass by 10%-20% with respect to pure N-body simulations. Our results suggest that rather than increasing the strength of the supernova-driven outflows, processes that reduce the star formation efficiency could help to solve the potential issues faced by CDM-based simulations of dwarfs, such as low values of the specific SFR and high stellar masses. [ABSTRACT FROM AUTHOR]

We extend the abundance matching technique (AMT) to infer the satellite-subhalo and central-halo mass relations (MRs) of local galaxies as well as the corresponding satellite conditional mass functions (CSMFs). We use as inputs the observed galaxy stellar mass function (GSMF) decomposed into centrals and satellites and the ΛCDM distinct halo and subhalo mass functions. We explore the effects of defining the subhalo mass, msub, at the time of (sub)halo accretion (maccsub) versus defining it at the time of observation (mobssub); we also test the standard assumption that centrals and satellites follow the same MRs. We show that this assumption leads to predictions in disagreement with observations, especially when mobssub is used. We find that when the satellite-subhalo MRs are constrained by the satellite GSMF, they are always different from the central-halo MR: The smaller the stellar mass, the less massive the subhalo of satellites as compared to the halo of centrals of the same stellar mass. This difference is more dramatic when mobssub is used instead of maccsub. On average, for stellar masses lower than ∼2 × 1011M☼, the dark mass of satellites decreased by 60%-65% with respect to their masses at accretion time. We find that MRs for both definitions of subhalo mass yield CSMFs in agreement with observations. Also, when these MRs are used in a halo occupation model, the predicted two-point correlation functions at different stellar mass bins agree with observations. The average stellar-halo MR is close to the MR of central galaxies alone, and conceptually this average MR is equivalent to abundance matching the cumulative total GSMF to the halo + subhalo mass function (the standard AMT). We show that the use of mobssub leads to less uncertain MRs than maccsub and discuss some implications of the obtained satellite-subhalo MR. For example, we show that the tension between abundance and dynamics of Milky Way satellites in the ΛCDM cosmogony gives a value of ∼ – 1.6 in the faint-end slope of the GSMF upturns. [ABSTRACT FROM AUTHOR]