Browsing by Author "Zibetti, S."
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- ItemCALIFA, the Calar Alto Legacy Integral Field Area survey IV. Third public data release(2016) Sánchez Blazquez, Patricia; Sánchez, S.; Garcia, R.; Zibetti, S.; Mendoza, M.; Galbany, L.; Falcon, J.; Mast, D.; Aceituno, J.; Aguerri, J.; Alves, J.; Amorim, A.; Ascasibar, Y.; Barrado, D.; Barrera, J.; Bland, J.
- ItemComprehensive comparison of models for spectral energy distributions from 0.1 μm to 1mm of nearby star-forming galaxies(2019) Hunt, L. K.; De Looze, I; Boquien, M.; Nikutta, R.; Rossi, A.; Bianchil, S.; Dale, D. A.; Granato, G. L.; Kennicutt, R. C.; Silva, L.; Ciesla, L.; Relano, M.; Viaene, S.; Brandl, B.; Calzetti, D.; Croxall, K., V; Draine, B. T.; Galametz, M.; Gordon, K. D.; Groves, B. A.; Helou, G.; Herrera-Camus, R.; Hinz, J. L.; Koda, J.; Salim, S.; Sandstrom, K. M.; Smith, J. D.; Wilson, C. D.; Zibetti, S.We have fit the far-ultraviolet (FUV) to sub-millimeter (850 mu m) spectral energy distributions (SEDs) of the 61 galaxies from the Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel (KINGFISH). The fitting has been performed using three models: the Code for Investigating GALaxy Evolution (CIGALE), the GRAphite-SILicate approach (GRASIL), and the Multiwavelength Analysis of Galaxy PHYSical properties (MAGPHYS). We have analyzed the results of the three codes in terms of the SED shapes, and by comparing the derived quantities with simple "recipes" for stellar mass (M-star), star-formation rate (SFR), dust mass (M-dust), and monochromatic luminosities. Although the algorithms rely on different assumptions for star-formation history, dust attenuation and dust reprocessing, they all well approximate the observed SEDs and are in generally good agreement for the associated quantities. However, the three codes show very different behavior in the mid-infrared regime: in the 5-10 mu m region dominated by PAH emission, and also between 25 and 70 mu m where there are no observational constraints for the KINGFISH sample. We find that different algorithms give discordant SFR estimates for galaxies with low specific SFR, and that the standard recipes for calculating FUV absorption overestimate the extinction compared to the SED-fitting results. Results also suggest that assuming a "standard" constant stellar mass-to-light ratio overestimates Mstar relative to the SED fitting, and we provide new SED-based formulations for estimating Mstar from WISE W1 (3.4 mu m) luminosities and colors. From a principal component analysis of M-star, SFR, M-dust, and O/H, we reproduce previous scaling relations among Mstar, SFR, and O/H, and find that Mdust can be predicted to within similar to 0.3 dex using only M-star and SFR.
- ItemIMF. shape constraints from stellar populations and dynamics from CALIFA(2016) Lyubenova, M.; Martın-Navarro, I.; van de Ven, G.; Falcon-Barroso, J.; Galbany, A.; Gallazzi, L.; Garcıa-Benito, R.; Gonzalez Delgado, R.; Husemann, B.; Sánchez Blazquez, Patricia; Marino, R. A.; Mast, D.; Mendez-Abreu, J.; Peletier, R. F. P.; La Barbera, F.; Sanchez, S. F.; Trager, S. C.; van den Bosch, R. C. E.; Vazdekis, A.; Walcher, C. J.; Zhu, L.; Zibetti, S.; Ziegler, B.; Bland-Hawthorn, J.
- ItemINSPIRE: INvestigating Stellar Population In RElics II. First data release (DR1)(2021) Spiniello, C.; Tortora, C.; D'Ago, G.; Coccato, L.; La Barbera, F.; Ferre-Mateu, A.; Pulsoni, C.; Arnaboldi, M.; Gallazzi, A.; Hunt, L.; Napolitano, N. R.; Radovich, M.; Scognamiglio, D.; Spavone, M.; Zibetti, S.Context. The INvestigating Stellar Population In RElics (INSPIRE) is an ongoing project targeting 52 ultra-compact massive galaxies at 0.1 < z < 0.5 with the X-shooter at VLT spectrograph (XSH). These objects are the ideal candidates to be `relics', massive red nuggets that have formed at high redshift (z > 2) through a short and intense star formation burst, and then have evolved passively and undisturbed until the present day. Relics provide a unique opportunity to study the mechanisms of star formation at high-z. Aims. INSPIRE is designed to spectroscopically confirm and fully characterise a large sample of relics, computing their number density in the redshift window 0:1 < z < 0:5 for the first time, thus providing a benchmark for cosmological galaxy formation simulations. In this paper, we present the INSPIRE Data Release (DR1), comprising 19 systems with observations completed in 2020. Methods. We use the methods already presented in the INSPIRE Pilot, but revisiting the 1D spectral extraction. For the 19 systems studied here, we obtain an estimate of the stellar velocity dispersion, fitting the two XSH arms (UVB and VIS) separately at their original spectral resolution to two spectra extracted in di fferent ways. We estimate [Mg /Fe] abundances via line-index strength and mass-weighted integrated stellar ages and metallicities with full spectral fitting on the combined (UVB +VIS) spectrum. Results. For each system, di fferent estimates of the velocity dispersion always agree within the errors. Spectroscopic ages are very old for 13 /19 galaxies, in agreement with the photometric ones, and metallicities are almost always (18 /19) super-solar, confirming the mass-metallicity relation. The [Mg /Fe] ratio is also larger than solar for the great majority of the galaxies, as expected. We find that ten objects formed more than 75% of their stellar mass (M-*) within 3 Gyr from the big bang and classify them as relics. Among these, we identify four galaxies that had already fully assembled their M-* by that time and are therefore `extreme relics' of the ancient Universe. Interestingly, relics, overall, have a larger [Mg /Fe] and a more metal-rich stellar population. They also have larger integrated velocity dispersion values compared to non-relics (both ultra-compact and normal-size) of similar stellar mass. Conclusions. The INSPIRE DR1 catalogue of ten known relics is the largest publicly available collection, augmenting the total number of confirmed relics by a factor of 3.3, and also enlarging the redshift window. The resulting lower limit for the number density of relics at 0.17 < z < 0.39 is rho similar to 9.1 x 10(-8) Mpc(-3).
- ItemINSPIRE: INvestigating Stellar Population In RElics III. Second data release (DR2): testing the systematics on the stellar velocity dispersion(2023) D'Ago, G.; Spiniello, C.; Coccato, L.; Tortora, C.; La Barbera, F.; Arnaboldi, M.; Bevacqua, D.; Ferre-Mateu, A.; Gallazzi, A.; Hartke, J.; Hunt, L. K.; Martin-Navarro, I.; Napolitano, N. R.; Pulsoni, C.; Radovich, M.; Saracco, P.; Scognamiglio, D.; Zibetti, S.Context. The project called INvestigating Stellar Population In RElics (INSPIRE) is based on VLT/X-shooter data from the homonymous on-going ESO Large Program. It targets 52 ultra-compact massive galaxies at 0.1 < z < 0.5 with the goal of constraining their kinematics and stellar population properties in great detail and of analysing their relic nature.
- ItemINSPIRE: INvestigating Stellar Population In RElics: I. Survey presentation and pilot study(2021) Spiniello, C.; Tortora, C.; D'Ago, G.; Coccato, L.; La Barbera, F.; Ferre-Mateu, A.; Napolitano, N. R.; Spavone, M.; Scognamiglio, D.; Arnaboldi, M.; Gallazzi, A.; Hunt, L.; Moehler, S.; Radovich, M.; Zibetti, S.Context. Massive elliptical galaxies are thought to form through a two-phase process. At early times (z> 2), an intense and fast starburst forms blue and disk-dominated galaxies. After quenching, the remaining structures become red, compact, and massive (i.e. red nuggets). Then, a time-extended second phase, which is dominated by mergers, causes structural evolution and size growth. Given the stochastic nature of mergers, a small fraction of red nuggets survive, without any interaction, massive and compact until today: these are relic galaxies. Since this fraction depends on the processes dominating the size growth, counting relics at low-z is a valuable way of disentangling between different galaxy evolution models.Aims. In this paper, we introduce the INvestigating Stellar Population In RElics (INSPIRE) Project, which aims to spectroscopically confirm and fully characterise a large number of relics at 0.1< z< 0.5. We focus here on the first results based on a pilot study targeting three systems, representative of the whole sample.Methods. For these three candidates, we extracted 1D optical spectra over an aperture of r=0.40 '', which comprises similar to 30% of the galaxies' light, and we obtained the line-of-sight integrated stellar velocity and velocity dispersion. We also inferred the stellar [alpha /Fe] abundance from line-index measurements and mass-weighted age and metallicity from full-spectral fitting with single stellar population models.Results. Two galaxies have large integrated stellar velocity dispersion values (sigma (star)similar to 250 km s(-1)), confirming their massive nature. They are populated by stars with super-solar metallicity and [alpha /Fe]. Both objects have formed >= 80% of their stellar mass within a short (similar to 0.5-1.0 Gyr) initial star formation episode occurred only similar to 1 Gyr after the Big Bang. The third galaxy has a more extended star formation history and a lower velocity dispersion. Thus we confirm two out of three candidates as relics.Conclusions. This paper is the first step towards assembling the final INSPIRE catalogue that will set stringent lower limits on the number density of relics at z< 0.5, thus constituting a benchmark for cosmological simulations, and their predictions on number densities, sizes, masses, and dynamical characteristics of these objects.
- ItemSPATIALLY. RESOLVED. STAR. FORMATION. MAIN. SEQUENCE. OF. GALAXIES. IN. THE. CALIFA. SURVEY(2016) Cano Díaz, M.; Sánchez, S. F.; Zibetti, S.; Ascasibar, Y.; Bland-Hawthorn, J.; Ziegler, B.; González Delgado, R. M.; Walcher, C. J.; García Benito, R.; Sánchez-Blázquez, P.; Mendoza-Pérez, M. A.; Falcón-Barroso, J.; Galbany, L.; Husemann, B.; Kehrig, C.; Marino, R. A.; Mast, D.; López-Cobá, C.; López-Sánchez, Á. R.; Vilchez, J. M.