Studying the properties of the few compact massive galaxies that exist in the local Universe (Trujillo et al. 2009) might provide a closer look to the nature of their high redshift (z ≥ 1.0) massive counterparts. By this means we have characterized their main kinematics, structural properties, stellar populations and star formation histories with a set of new high quality spectroscopic and imaging data (Ferré-Mateu et al. 2012 and Trujillo et al. 2012). These galaxies seem to be truly unique, as they do not follow the characteristic kinematics, stellar surface mass density profiles and stellar population patterns of present-day massive ellipticals or spirals of similar mass. They are, instead, more alike their high-z analogs.

Summarizing, local compact massive galaxies are rare, unique and the perfect laboratory to study their high redshift counterparts.

Supermassive black holes (BHs) have been found in 75 galaxies by observing spatially resolved dynamics. The Hubble Space Telescope (HST) revolutionized BH work by advancing the subject from its ‘proof of concept’ phase into quantitative studies of BH demographics. Most influential was the discovery of a tight correlation between BH masses M• and the velocity dispersions σ of stars in the host galaxy bulge components at radii where the stars mostly feel each other and not the BH. Together with correlations between M• and bulge luminosity, with the ‘missing light’ that defines galaxy cores, and with numbers of globular clusters, this has led to the conclusion that BHs and bulges coevolve by regulating each other's growth. This simple picture with one set of correlations for all galaxies dominated BH work in the past decade.

New results are now replacing the above, simple story with a richer and more plausible picture in which BHs correlate differently with different kinds of galaxy components. BHs with masses of 105—106M⊙ live in some bulgeless galaxies. So classical (merger-built) bulges are not necessary equipment for BH formation. On the other hand, while they live in galaxy disks, BHs do not correlate with galaxy disks or with disk-grown pseudobulges. They also have no special correlation with dark matter halos beyond the fact that halo gravity controls galaxy formation. This leads to the suggestion that there are two modes of BH feeding, (1) local, secular and episodic feeding of small BHs in largely bulgeless galaxies that involves too little energy feedback to drive BH–host-galaxy coevolution and (2) global feeding in major galaxy mergers that rapidly grows giant BHs in short-duration events whose energy feedback does affect galaxy formation. After these quasar-like phases, maintenance-mode BH feedback into hot, X-ray-emitting gas continues to have a primarily negative effect in preventing late-time star formation when cold gas or gas-rich galaxies get accreted. Finally, the highest-mass galaxies inherit coevolution effects from smaller galaxies; the tightness of their BH correlations is caused mainly by averaging during dissipationless major mergers.

Massive galaxies harbor a supermassive black hole at their centers. At high redshifts, these galaxies experienced a very active quasar phase, when, as their black holes grew by accretion, they produced enormous amounts of energy. At the present epoch, these black holes still undergo occasional outbursts, although the mode of their energy release is primarily mechanical rather than radiative. The energy from these outbursts can reheat the cooling gas in the galaxy cores and maintain the red and dead nature of the early-type galaxies. These outbursts also can have dramatic effects on the galaxy-scale hot coronae found in the more massive galaxies. We describe research in three areas related to the hot gas around galaxies and their supermassive black holes. First we present examples of galaxies with AGN outbursts that have been studied in detail. Second, we show that X-ray emitting low-luminosity AGN are present in 80% of the galaxies studied. Third, we discuss the first examples of extensive hot gas and dark matter halos in optically faint galaxies.

We discuss the effects of supermassive black hole (SMBH) outbursts on the hot atmospheres surrounding the central massive galaxies in groups and clusters, as observed with X-ray and radio observations. We focus on a detailed study of the supermassive black hole in M87 at the center of the Virgo cluster using Chandra and VLA observations. We summarize the outburst history and describe the clearly observed energy input from buoyant bubbles of relativistic plasma produced by the central SMBH, uplifted filaments of X-ray emitting gas, and the Mach 1.2 shock together balance the energy lost as gas radiatively cools.

Black hole binaries form after major galaxy mergers, but their fate is unclear as hardening due to stars gets inefficient at sub-parsec distances. We model an alternative scenario in which the merger is driven by the interaction of the binary with the surrounding gas.†

The possibility of UV lines from Fe II formed in the BLR of NGC 4151 has been examined. As a result Fe II emission has been shown to play an important role for the topology of the 2000 to 3000 Å wavelength region of the NGC 4151 spectra. The Fe II UV emission originates from two processes, collisional excitation and PAR (photoexcitation by accidental resonance).

We propose a mechanism that contributes energy and particles to the diffuse x-ray halos of galaxies and clusters, based on the dark quantum states of large-scale gravity wells.

We investigate the properties of the galaxies hosting quasars in ~400 low redshift (z < 0.5) SDSS QSO that are in the “Stripe 82” sky area. For this region deep (r ~ 22.4 mag) u, b, v, r and i images are available and allow us to study both the host galaxies and the Mpc scale environments. This sample outnumbers previous studies of low-z QSOs. We present preliminary results of the properties of quasars activity and in particular we focus on the relationships among host galaxy luminosity, black hole mass, radio emission and the surrounding galaxy environments. We select from the SDSS - QSO Catalogue all the QSOs in the range of redshift 0.1<z<0.5 and in the Stripe82 region. This gives a total of 416 QSO. In this sample we are dominated by radio quiet quasars (about 5% are radio loud). In Fig. 1 we report the distribution of QSO in the plane redshift-MR (H0 = 70). The mean redshift of the sample is <z> = 0.39 and the average absolute magnitude is: <Mi> = −22.68. We implemented an automated procedure using AIDA (Uslenghi & Falomo 2011) to decompose the QSO images into nucleus and host galaxy luminosity. After masking of all contaminating sources in the field a 2D fitting is performed using PSF + galaxy model. In Fig. 1 we show an example of a QSO image in the sample and the distribution of the host galaxy absolute magnitude of the resolved objects.

We use the spatially resolved gas-phase metallicity as a new diagnostic for tagging recent interactions in QSO host galaxies. With this technique we also identified a QSO with extremely low gas-phase metallicity as likely evidence for gas accretion from the environment.

We study the host galaxy properties of radio sources in the AKARI-North Ecliptic Pole (NEP) field, using an ensemble of multi-wavelength datasets. We identify both radio-loud and radio-quiet AGN and study their host galaxy properties by means of SED fitting. We investigate the relative importance of nuclear and star-formation activity in radio-AGN and assess the role of radio-AGN as efficient quenchers of star-formation in their host galaxies.

The final episode in the history of black hole accretion and galaxy formation takes place in our cosmic backyard, the local universe. Within this volume must also reside the — until now unknown — sources of observed ultra-high energy cosmic rays (UHECRs). A thorough study of the local universe requires full-sky coverage to obtain a sizable sample and map the matter anisotropy. We recently constructed the first catalog of radio-emitting galaxies that meets this requirement. The sample contains all radio galaxies similar to Centaurus~A out to ~100 Mpc. Only 3% of the hosts of the powerful radio jets are classified as Spiral galaxies, while for non-radio galaxies of similar mass, this fraction is 34%. The energy injected by radio jets per unit volume indicates that Cen A-like radio galaxies have in principle sufficient power to accelerate cosmic rays to ultra-high energies. A significantly enhanced clustering of radio-loud galaxies compared to normal galaxies of the same luminosity is observed. This indicates a causal relation between galaxy environment and jet power, independent of black hole mass.

Modelling stellar populations in galaxies is a key approach to gain knowledge on the still elusive process of galaxy formation as a function of cosmic time. In this review, after a summary of the state-of-art, I discuss three aspects of the modelling, that are particularly relevant to massive galaxies, the focus of this symposium, at low and high-redshift. These are the treatment of the Thermally-Pulsating Asymptotic Giant Branch phase, evidences of an unusual Initial Mass Function, and the effect of modern stellar libraries on the model spectral energy distribution.

We show that Monte Carlo simulations of the TP-AGB stellar population in the LMC and SMC galaxies using the CB* models produce LF and color distributions that are in closer agreement with observations than those obtained with the BC03 and CB07 models. This is a progress report of work that will be published elsewhere.

Templates and models of galaxy spectra are often essential for determining the physical properties of galaxies. Many commonly used templates have large systematic errors, which significantly impact photometric redshifts and k-corrections. We present a new library of 110 galaxy template spectra spanning from the ultraviolet to the mid-infrared. The templates combine optical, Spitzer and Akari spectra with MAGPHYS models, all normalised and verified with matched aperture photometry. Our library contains more galaxies, spans a broader range of colours and has smaller systematic errors than previous libraries of galaxy spectra.

I present a brief review of the stellar population properties of massive galaxies, focusing on early-type galaxies in particular, with emphasis on recent results from the ATLAS3D Survey. I discuss the occurence of young stellar ages, cold gas, and ongoing star formation in early-type galaxies, the presence of which gives important clues to the evolutionary path of these galaxies. Consideration of empirical star formation histories gives a meaningful picture of galaxy stellar population properties, and allows accurate comparison of mass estimates from populations and dynamics. This has recently provided strong evidence of a non-universal IMF, as supported by other recent evidences. Spatially-resolved studies of stellar populations are also crucial to connect distinct components within galaxies to spatial structures seen in other wavelengths or parameters. Stellar populations in the faint outer envelopes of early-type galaxies are a formidable frontier for observers, but promise to put constraints on the ratio of accreted stellar mass versus that formed ‘in situ’ - a key feature of recent galaxy formation models. Galaxy environment appears to play a key role in controlling the stellar population properties of low mass galaxies. Simulations remind us, however, that current day galaxies are the product of a complex assembly and environment history, which gives rise to the trends we see. This has strong implications for our interpretation of environmental trends.

The Calar Alto Legacy Integral Field Area (CALIFA) project is an ongoing 3D spectroscopic survey of 600 nearby galaxies of all kinds. This pioneer survey is providing valuable clues on how galaxies form and evolve. Processed through spectral synthesis techniques, CALIFA datacubes allow us to, for the first time, spatially resolve the star formation history of galaxies spread across the color-magnitude diagram. The richness of this approach is already evident from the results obtained for the first ~ 1/6 of the sample. Here we show how the different galactic spatial sub-components (“bulge” and “disk”) grow their stellar mass over time. We explore the results stacking galaxies in mass bins, finding that, except at the lowest masses, galaxies grow inside-out, and that the growth rate depends on a galaxy's mass. The growth rate of inner and outer regions differ maximally at intermediate masses. We also find a good correlation between the age radial gradient and the stellar mass density, suggesting that the local density is a main driver of galaxy evolution.

We study relationships between the stellar populations and interstellar medium in massive galaxies using the Galex Arecibo SDSS Survey (GASS). The sample consists of HI-observations (~1000 galaxies) and complementary H2-observations (330 galaxies) and long-slit spectroscopy (230 galaxies). Luminosity-weighted stellar population ages, metallicitites and element abundance ratios, are derived by fitting stellar population models of absorption line indices. We find that the ages correlate more strongly with molecular gas fraction (MH2/M*) than with neutral Hydrogen fraction (MHI/M*). This result strengthens the theory that H2 is a better tracer of star-formation than HI. The sample is dominated by negative metallicity-gradients and flat Mg/Fe-gradients. Galaxies with high MH2/M*-ratios show in general flat or weakly negative age-gradients. For low MH2/M*-ratios the age-gradients are overall negative. These results are in agreement with the inside-out galaxy formation scenario. For galaxies with high r90/r50-ratios, a sub-population show positive age-gradients indicating additional formation channels. Furthermore, for galaxies with high MH2/M*-ratios more massive systems have older stellar populations in their centers, suggesting downsizing within the inside-out formation scenario.

Examining both optical and optical-infrared color distributions of the globular cluster (GC) systems in large elliptical galaxies is the key to study how non-linearities in the color-metallicity relations of their GC systems are linked to bimodal optical color distributions. In order to do this for the core of the Coma cluster of galaxies (Abell 1656), centered on the giant elliptical galaxy NGC 4874, we have combined F160W (H160) near-infrared (NIR) imaging data acquired with the Wide Field Camera 3 IR Channel (WFC3/IR), installed on Hubble Space Telescope (HST) in 2009, with F475W (g475) and F814W (I814) optical imaging data from the HST Advanced Camera for Surveys (ACS). Since optical-NIR color distributions of extragalactic GC systems reflect the underlying features of the metallicity distributions, we have probed not only optical g475–I814 and optical-NIR I814–H160 color distributions but also the color-color relation for this GC system. The features of these color distributions have been quantitatively analyzed using the Gaussian Mixture Modeling code. We find that brighter GCs have a much redder mean color than fainter ones. The optical color distribution of the GC system in the Coma cluster core shows the typical bimodality, while the evidence for bimodality is significantly weaker in the optical-NIR color distribution.

Based on the South Galactic Cap U-band Sky Survey (SCUSS) and SDSS observations, we adopted the star-count method to analyze the stellar distribution in different directions of the Galaxy. We find that the scale height of the disk may be variable with the observed direction, which cannot simply be attributed to statistical errors. The main reason can be possibly attributed to the disk (mainly the thick disk) being flared, with a scale height increasing with radius. The axis ratio of the Galactic halo is in the range 0.4-0.6. This finding supports Galactic models with a flattened inner halo, partly formed through a merger early in the Galaxy's history.

Interactions and mergers are important drivers of galaxy evolution, transform spiral galaxies into massive ellipticals, and fuel both powerful starbursts and massive nuclear black holes. In particular one galaxy population, namely Luminous Infrared Galaxies (LIRGs), are believed to be responsible for most of the star formation that happened in the history of the universe (see e.g. Le Floch et al. 2005, Caputi et al. 2007, Magnelli et al. 2009), and hence represent a critical phase in the evolution of galaxies where most of the galaxies mass is building up. During a merger process, violent relaxation acts on stars present in gas-rich progenitor disks, while the centers are structured by the relics of dissipational, compact starbursts, imprinting a central “extra light” component or “cusp” into the surface brightness profiles of merger remnants. Our HST NICMOS/WFC3 imaging program of the 88 most luminous LIRGs in the Great Observatories Allsky LIRG Survey (GOALS, see Armus et al. 2009) shows that the central luminosity surface density in nearby LIRGs increases significantly along the merger sequence, indicating that the gas inflow fuels a central starburst and subsequently builds a compact stellar cusp (Haan et al. 2011). A large fraction of all galaxies in our sample possess double or multiple nuclei (~63%). Half of these double nuclei are not visible in the HST B-band images due to dust obscuration, which implies strong limitations on the ability to detect the true nuclear structures of luminous infrared galaxies at high-redshift (z >2) and may explain some of the apparent discrepancy of the LIRG population and merger ratio between local and high-redshift galaxies. We find that ULIRGs (log[LIR/L⊙] > 12.0) have significantly smaller nuclear separations than LIRGs (log[LIR/L⊙] = 11.4 — 12.0) with a median value of 1.2 kpc and 6.7 kpc, respectively. In our sample, merger (regardless of whether LIRG or ULIRG) seem to be prevalent at two time scales (based on the projected nuclear separation and mass ratio of the nuclei): First, at a remaining merger time scale of 0.3<[t-tmerg]<1.3 Gyr (53% of mergers in our sample), and second, at [t-tmerg]~ 0 (26%), likely representing the first passage of interacting galaxies and the final nuclear coalescence, respectively, with a post-merger time (starburst phase after the nuclei merged) of roughly 300 Myrs.