Probing the rapid formation of black holes and their galaxy hosts in QSOs

Using the modelling code X-CIGALE, we reproduced the SEDs of 1,359 SDSS QSOs within the redshift range 0 < z < 4, for which we have NIR/MIR fluxes with the highest quality and spectral data characterizing their SMBHs. Consistent with a rapid formation of the host galaxies, the star formation histories (SFHs) have small e-folding, at most 750 Myrs using an SFH function for Spiral or 1000 Myrs using one for Elliptical. Above z \sim 1.6, the two solutions are degenerate, the SEDs being dominated by the AGN continuum and high star formation rates (SFRs), typical of starburst galaxies, while at lower redshifts the starburst nature of the host, independent from its morphology, is better reproduced by an Spiral SFH. In general, the SFR increases with the redshift, the mass of the bulge, the AGN luminosity and Eddington ratio, suggesting there is no evidence of AGN quenching of star formation. Comparing the specific BHAR with specific SFR, all the QSOs at any redshift trace a linear sequence below the Eddington luminosity, in parallel and above the one-to-one relation, implying that QSOs are in a special phase of evolution during which the growth in mass of their SMBH is more rapid than the growth in mass of their galaxy hosts. This particular phase is consistent with a scenario where the galaxy hosts of QSOs in the past grew in mass more rapidly than their SMBHs, suggesting that a high star formation efficiency during their formation was responsible in limiting their massesComment: Accepted in MNRAS 2023 February 28. Received 2023 February 28; in original form 2022 July 0

Star formation in CALIFA survey perturbed galaxies.III. Stellar & ionized-gas kinematic distributions

We obtain the kinematic distributions of stars (synthetic model line absorption) and ionized gas (H$\alpha$ line emission) for star-forming regions residing in CALIFA survey tidally perturbed (perturbed) and non-tidally perturbed (control) galaxies. We set the uncertainties of the velocity dispersion by measuring the statistical variability of the datasets themselves. Using these adopted uncertainties and considering the sensitivity of the grating device, we establish thresholds of reliability that allow us to select reliable velocity dispersions. From this selection, we pair the star-forming spaxels between control and perturbed galaxies at the closest shifts in velocity (de-redshifting). We compare their respective distributions of velocity dispersion. In perturbed galaxies, median velocity dispersions for the stellar and gaseous components are minimally higher and equal, respectively, than those in control galaxies. The spread in velocity dispersion and the velocity shift - velocity dispersion space agree with this result. Unlike the well-known trend in strongly interacting systems, the stellar and ionized-gas motions are not disturbed by the influence of close companions. For the gaseous component, this result is due to the poor statistical variability of its data, a consequence of the tightness in velocity dispersion derived from high spectral line intensities. This analysis concludes the series, which previously showed star-forming regions in galaxies with close companions undergoing more prominent gas inflows, resulting in differences in their star formation and consequent metal content

The Role of Active Galactic Nucleus Winds in Galaxy Formation: Connecting AGN Outflows at Low Redshifts to the Formation/Evolution of Their Host Galaxies

Using Sloan Digital Sky Survey (SDSS) spectra, we applied an automatic method to search for outflows (OFs) in three large samples of narrow-line active galactic nuclei (AGN) at low redshifts ( z < 0.4), separated into three spectral activity classes: radio-loud galaxies (RGs), 15,793; radio-quiet Seyfert 2 AGN (Sy2), 18,585; and LINERs, 25,656. In general, the probability of detecting an OF decreases along the sequence Sy1→Sy2→LINER/RG and independently of the AGN class, the wind velocity, traced by W 80, increases with the AGN luminosity. Moreover W 80 is systematically higher in RGs or any of the other AGN classes when detected in radio. These results support the idea that there are two main modes of production of OF, the radiative mode dominant in radio-quiet AGN and the jet mode dominant in RGs, although both modes could also happen simultaneously at different levels. From the spectra and SDSS photometry, the characteristics of the AGN host galaxies and their supermassive black holes (SMBHs) were also retrieved using the stellar population synthesis code STARLIGHT. This revealed that, independently of the AGN spectral class, (1) galaxy hosts with OFs have systematically later morphological types and higher star formation rates (SFRs) than their counterparts without OF, (2) the AGN occupy different positions in the specific diagnostic diagram (specific black hole accretion rate (sBHAR) versus specific SFR), which suggests they follow different evolutionary paths congruent with the morphology of their galaxy hosts, and (3) they show no evidence of AGN quenching or triggering of star formation. These results are consistent with a scenario explaining the different AGN classes as consequences of different formation processes of galaxies: early-type galaxies (LINERs and RGs) formed bigger bulges and more massive SMBHs, exhausting their reservoir of gas more rapidly than late-type galaxies (Sy2 and Sy1), and thereby quenching their star formation and starving their SMBHs

Eight years after IYA2009: a successful project of Outreach and Astronomy Education on selected countryside towns in Mexico

We present the main results of a multidisciplinary project on education and outreach in Guanajuato (Mexico). This collaboration was initiated in the International Year of Astronomy (IYA09, IAU-UNESCO, 2009) and is led by a team including astronomers, sociologists and environment biologists. The Astronomy activities had their origin at the Public Observatory of Universidad de Guanajuato, where an outreach program was dedicated to young students, teachers and the general public. Thanks to the many activities linked to IYA09, the astronomers joined with a group of sociologists working on the development of rural zones of the Mexican State of Guanajuato. This region undergoes a high rate of migration towards the USA. Working together, our goals were enlarged, having important results on different aspects like social development, environment recovering and education. Astronomy plays a central role within this project, mainly through activities like stargazing, science games for young public, Astronomy courses for teachers, and talks for a wide audience

Eight years after IYA2009: a successful project of Outreach and Astronomy Education on selected countryside towns in Mexico

We present the main results of a multidisciplinary project on education and outreach in Guanajuato (Mexico). This collaboration was initiated in the International Year of Astronomy (IYA09, IAU-UNESCO, 2009) and is led by a team including astronomers, sociologists and environment biologists. The Astronomy activities had their origin at the Public Observatory of Universidad de Guanajuato, where an outreach program was dedicated to young students, teachers and the general public. Thanks to the many activities linked to IYA09, the astronomers joined with a group of sociologists working on the development of rural zones of the Mexican State of Guanajuato. This region undergoes a high rate of migration towards the USA. Working together, our goals were enlarged, having important results on different aspects like social development, environment recovering and education. Astronomy plays a central role within this project, mainly through activities like stargazing, science games for young public, Astronomy courses for teachers, and talks for a wide audience

Eight years after IYA2009: a successful project of Outreach and Astronomy Education on selected countryside towns in Mexico

We present the main results of a multidisciplinary project on education and outreach in Guanajuato (Mexico). This collaboration was initiated in the International Year of Astronomy (IYA09, IAU-UNESCO, 2009) and is led by a team including astronomers, sociologists and environment biologists. The Astronomy activities had their origin at the Public Observatory of Universidad de Guanajuato, where an outreach program was dedicated to young students, teachers and the general public. Thanks to the many activities linked to IYA09, the astronomers joined with a group of sociologists working on the development of rural zones of the Mexican State of Guanajuato. This region undergoes a high rate of migration towards the USA. Working together, our goals were enlarged, having important results on different aspects like social development, environment recovering and education. Astronomy plays a central role within this project, mainly through activities like stargazing, science games for young public, Astronomy courses for teachers, and talks for a wide audience

Star formation intensities of non-isolated galaxies with the CALIFA survey

Poster presented at the conference Galaxy Evolution Across Time, 12-16 June, Paris, France. The influence of interactions on the star formation (SF) is investigated by studying a sample of 34 CALIFA survey non-isolated galaxies. We use the instantaneous star formation rate intensity (SFRI) obtained from the Halpha recombination line emission normalized by a unit of projected area. We explore the SFRI, stellar mass and stellar age annulus structures (split by morphology group), also for a control population of star-forming isolated galaxies observed with the CALIFA survey likewise. By morphology groups, the SF efficiency of early type spirals (ETSs) results magnified likely because of angular momentum loss. The SFRI of the non-isolated sample is then compared with that one of the isolated sample. It is found statistically and moderately enhanced in the non-isolated sample by a factor of at most 2. We also find the SFRI as to be a function of the degree of tidal perturbation what might consequently suggest interactions as to facilitate the gas transport to central regions. Contrasting behaviors of the SFRI structures, a gradual quench with clear outer presence of SF (isolated sample) while a steeper decrease from the center with poor SFRIs outwards (non-isolated one) are found. Similitudes in a variety of stellar population properties support the closeness of companions as to be the cause of the SFRI differences between samples