Examinando por Autor "Costantin, Luca"

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Acceso Abierto
A few StePS forward in unveiling the complexity of galaxy evolution: light-weighted stellar ages of intermediate-redshift galaxies with WEAVE
(EDP Sciences, 2019-11-21) Costantin, Luca; Lovino, A.; Zibetti, S.; Longhetti, M.; Gallazzi, A.; Mercurio, A.; Lonoce, I.; Balcells, M.; Bolzonella, M.; Busarello, G.; Dalton, G.; Ferré Mateu, A.; García Benito, R.; Gargiulo, A.; Haines, C.; Jin, S.; La Barbera, F.; McGee, S.; Merluzzi, P.; Morelli, L.; Murphy, D. N. A.; Peralta de Arriba, L.; Pizzella, A.; Poggianti, B. M.; Pozzetti, L.; Sánchez Blázquez, Patricia; Talia, M.; Tortora, C.; Trager, S. C.; Vazdekis, A.; Vergani, D.; Vulcani, B.; Istituto Nazionale di Astrofisica (INAF); Comunidad de Madrid; Fundación Caixa; Agencia Estatal de Investigación (AEI); Vulcani, B. [0000-0003-0980-1499]; De Arribas, L. P. [0000-0002-3084-084X]; Zibetti, S. [0000-0003-1734-8356]; Talia, M. [0000-0003-4352-2063]; Tortora, C. [0000-0001-7958-6531]; Pizzella, A. [0000-0001-9585-417X]; Ferré Mateu, A. [0000-0002-6411-220X]; McGee, S. [0000-0003-3255-3139]; Gargiulo, A. [0000-0002-3351-1216]; Longhetti, M. [0000-0002-6142-4822]; Gallazzi, A. [0000-0002-9656-1800]; Vergani, D. [0000-0003-0898-2216]; Haines, C. [0000-0002-8814-8960]; Costantin, L. [0000-0001-6820-0015]; Pozzetti, L. [0000-0001-7085-0412]; Dalton, G. [0000-0002-3031-2588]; Iovino, A. [0000-0001-6958-0304]; Sánchez Blázquez, P. [0000-0003-0651-0098]; Merluzzi, P. [0000-0003-3966-2397]; Centros de Excelencia Severo Ochoa, INSTITUTO DE ASTROFISICA DE ANDALUCIA (IAA), SEV-2017-0709; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. The upcoming new generation of optical spectrographs on four-meter-class telescopes, with their huge multiplexing capabilities, excellent spectral resolution, and unprecedented wavelength coverage, will provide invaluable information for reconstructing the history of star formation in individual galaxies up to redshifts of about 0.7. Aims. We aim at defining simple but robust and meaningful physical parameters that can be used to trace the coexistence of widely diverse stellar components: younger stellar populations superimposed on the bulk of older ones. Methods. We produced spectra of galaxies closely mimicking data from the forthcoming Stellar Populations at intermediate redshifts Survey (StePS), a survey that uses the WEAVE spectrograph on the William Herschel Telescope. First, we assessed our ability to reliably measure both ultraviolet and optical spectral indices in galaxies of different spectral types for typically expected signal-to-noise ratios. We then analyzed such mock spectra with a Bayesian approach, deriving the probability density function of r- and u-band light-weighted ages as well as of their difference. Results. We find that the ultraviolet indices significantly narrow the uncertainties in estimating the r- and u-band light-weighted ages and their difference in individual galaxies. These diagnostics, robustly retrievable for large galaxy samples even when observed at moderate signal-to-noise ratios, allow us to identify secondary episodes of star formation up to an age of ∼0.1 Gyr for stellar populations older than ∼1.5 Gyr, pushing up to an age of ∼1 Gyr for stellar populations older than ∼5 Gyr. Conclusions. The difference between r-band and u-band light-weighted ages is shown to be a powerful diagnostic to characterize and constrain extended star-formation histories and the presence of young stellar populations on top of older ones. This parameter can be used to explore the interplay between different galaxy star-formation histories and physical parameters such as galaxy mass, size, morphology, and environment.
Restringido
Accelerated quenching and chemical enhancement of massive galaxies in a z ≈ 4 gas-rich halo
(Nature Astronomy, 2025-07-21) Pérez-González, Pablo G.; D'Eugenio, Francesco; Rodriguez Del Pino, Bruno; Perna, Michele; Übler, Hannah; Maiolino, Roberto; Arribas, Santiago; Cresci, Giovanni; Lamperti, Isabella; Bunker, Andrew J.; Carniani, Stefano; Willott, Chris J.; Böker, Torsten; Parlanti, Eleonora; Scholtz, Jan; Venturi, Giacomo; Barro, Guillermo; Costantin, Luca; Martin-Navarro, Ignacio; Dunlop, James S.; Magee, Daniel; Ministerio de Ciencia e Innovación (MICINN); Agencia Estatal de Investigación (España); European Commission; Science and Technology Facilities Council (STFC); European Research Council (ERC); Istituto Nazionale di Astrofisica (INAF); Fundación La Caixa
Stars in galaxies form when baryons radiatively cool down and fall into gravitational wells whose mass is dominated by dark matter. Eventually, star formation quenches as gas is depleted and/or perturbed by feedback processes, no longer being able to collapse and condense. We report the first spatially resolved spectroscopic observations, using the JWST/NIRSpec IFU, of a massive, completely quiescent galaxy (Jekyll) and its neighborhood at $z=3.714$, when the Universe age was 10% of today's. Jekyll resides in a massive dark matter halo (with mass M$_\mathrm{DM}>10^{12}$ M$_\odot$) and forms a galaxy pair with Hyde, which shows very intense dust-enshrouded star formation (star formation rate $\sim300$ M$_\odot$yr$^{-1}$). We find large amounts of kinematically perturbed ionized and neutral gas in the circumgalactic medium around the pair. Despite this large gas reservoir, Jekyll, which formed $10^{11}$ M$_\odot$ in stars and chemically enriched early (first billion years of the Universe) and quickly (200-300 Myr), has remained quiescent for over 500 Myr. The properties of the gas found around the two galaxies are consistent with intense, AGN-induced photoionization, or intense shocks. However, with the current data no obscured or unobscured AGN is detected in the central galaxy (Jekyll) nor in the very active and dust rich star-forming galaxy (Hyde).
Acceso Abierto
Dynamical Structure of Small Bulges Reveals Their Early Formation in ΛCDM Paradigm
(The Institute of Physics (IOP), 2020-01-17) Costantin, Luca; Méndez Abreu, J.; Corsini, E. M.; Morelli, L.; De Lorenzo Cáceres, A.; Pagotto, I.; Cuomo, V.; Aguerri, J. A. L.; Rubino, M.; Comunidad de Madrid; Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO); Ministero dell'Istruzione, dell'Università e della Ricerca (MIUR); 0000-0001-6820-0015; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The Λ cold dark matter (ΛCDM) paradigm of galaxy formation predicts that dense spheroidal stellar structures invariably grow at early cosmic time. These primordial spheroids evolve toward a virialized dynamical status as they finally become today's elliptical galaxies and large bulges at the center of disk galaxies. However, observations reveal that small bulges in spiral galaxies are common in the nearby universe. The prevailing belief that all small bulges form at later times from internal processes occurring in the disk represents a challenge for the ΛCDM scenario. Notably, the coevolution of bulges and central supermassive black holes (SMBHs) at early phases of galaxy evolution is also at stake. However, observations have so far not provided conclusive evidence against their possible early origin. Here, we report new observations of small bulges showing that they follow the mass–velocity dispersion relation expected for virialized systems. Contrary to previous claims, small bulges bridge the gap between massive ellipticals and globular clusters. This dynamical picture supports a scenario where systems over seven orders of magnitude in stellar mass form at early cosmic time. These results alleviate the tension between ΛCDM simulations and observations at galactic scales. We hypothesize that these small bulges are actually the low-mass descendants of compact objects observed at high redshift, also known as red nuggets, which are consistently produced in cosmological ΛCDM simulations. Therefore, this also suggests that the established coevolution of SMBHs and large bulges naturally extends to spheroids in the low-mass regime.
Acceso Abierto
Physics of ULIRGs with MUSE and ALMA: The PUMA project III. Incidence and properties of ionised gas disks in ULIRGs, associated velocity dispersion, and its dependence on starburstiness
(EDP Sciences, 2022-06-23) Perna, Michele; Arribas, Santiago; Colina, L. ; Pereira Santaella, Miguel; Lamperti, Isabella; Di Teodoro, Enrico M.; Übler, Hannah; Costantin, Luca; Maiolino, R.; Cresci, Giovanni; Bellocchi, Enrica ; Catalán Torrecilla, Cristina; Cazzoli, Sara; Piqueras López, Javier; European Research Council (ERC); European Commission; Ministerio de Ciencia e Innovación (MICINN); Comunidad de Madrid; Centros de Excelencia Severo Ochoa, INSTITUTO DE ASTROFISICA DE ANDALUCIA (IAA), SEV-2017-0709
Context. A classical scenario suggests that ultra-luminous infrared galaxies (ULIRGs) transform colliding spiral galaxies into a spheroid-dominated early-type galaxy. Recent high-resolution simulations have instead shown that, under some circumstances, rotation disks can be preserved during the merging process or rapidly regrown after coalescence. Our goal is to analyse in detail the ionised gas kinematics in a sample of ULIRGs to infer the incidence of gas rotational dynamics in late-stage interacting galaxies and merger remnants. Aims. We analysed integral field spectrograph MUSE data of a sample of 20 nearby (z < 0.165) ULIRGs (with 29 individual nuclei) as part of the Physics of ULIRGs with MUSE and ALMA (PUMA) project. We used multi-Gaussian fitting techniques to identify gaseous disk motions and the 3D-Barolo tool to model them. Methods. We found that 27% (8 out of 29) individual nuclei are associated with kiloparsec-scale disk-like gas motions. The rest of the sample displays a plethora of gas kinematics, dominated by winds and merger-induced flows, which makes the detection of rotation signatures difficult. On the other hand, the incidence of stellar disk-like motions is ∼2 times larger than gaseous disks, as the former are probably less affected by winds and streams. The eight galaxies with a gaseous disk present relatively high intrinsic gas velocity dispersion (σ0 ∈ [30 − 85] km s−1), rotationally supported motions (with gas rotation velocity over velocity dispersion vrot/σ0 ∼ 1 − 8), and dynamical masses in the range (2 − 7)×1010 M⊙. By combining our results with those of local and high-z disk galaxies (up to z ∼ 2) from the literature, we found a significant correlation between σ0 and the offset from the main sequence (δMS), after correcting for their evolutionary trends. Results. Our results confirm the presence of kiloparsec-scale rotating disks in interacting galaxies and merger remnants in the PUMA sample, with an incidence going from 27% (gas) to ≲50% (stars). Their gas σ0 is up to a factor of ∼4 higher than in local normal main sequence galaxies, similar to high-z starbursts as presented in the literature; this suggests that interactions and mergers enhance the star formation rate while simultaneously increasing the velocity dispersion in the interstellar medium. © ESO 2022.
Acceso Abierto
Reionization and the ISM/Stellar Origins with JWST and ALMA (RIOJA): The Core of the Highest-redshift Galaxy Overdensity at z = 7.88 Confirmed by NIRSpec/JWST
(American Astronomical Society, 2023-09-01) Hashimoto, T., T.; Álvarez-Márquez, J., J.; Fudamoto, Y.; Colina, L.; Inoue, A. K.; Nakazato, Y.; Ceverino, D.; Yoshida, N.; Costantin, Luca; Sugahara, Y.; Gómez Crespo, A.; Blanco-Prieto, C.; Mawatari, K.; Arribas, Santiago; Marques-Chaves, R.; González, E. M.; Bakx, T. J.L.C.; Hagimoto, M.; Hashigaya, T.; Matsuo, H.; Tamura, Y.; Usui, M.; Ren, Y. W.; Japan Society for the Promotion of Science (KAKENHI); Ministerio de Ciencia e Innovación (MICINN); Ministry of Education, Science, Sports and Culture (MEXT); National Astronomical Observatory of Japan (NAOJ); Comunidad de Madrid; The European Space Agency (ESA)
The protoclusters in the epoch of reionization, traced by galaxy overdensity regions, are ideal laboratories for studying the process of stellar assembly and cosmic reionization. We present the spectroscopic confirmation of the core of the most distant protocluster at z = 7.88, A2744-z7p9OD, with the James Webb Space Telescope NIRSpec integral field unit spectroscopy. The core region includes as many as four galaxies detected in [O iii] 4960 and 5008 Å in a small area of ∼3″ × 3″, corresponding to ∼11 × 11 kpc, after the lensing magnification correction. Three member galaxies are also tentatively detected in dust continuum in Atacama Large Millimeter/submillimeter Array Band 6, which is consistent with their red ultraviolet continuum slopes, β ∼ −1.3. The member galaxies have stellar masses in the range of log(M */M ⊙) ∼7.6-9.2 and star formation rates of ∼3-50 M ⊙ yr−1, showing a diversity in their properties. FirstLight cosmological simulations reproduce the physical properties of the member galaxies including the stellar mass, [O iii] luminosity, and dust-to-stellar mass ratio, and predict that the member galaxies are on the verge of merging in a few to several tens of Myr to become a large galaxy with M * ∼ 6 × 109 M ⊙. The presence of a multiple merger and evolved galaxies in the core region of A2744-z7p9OD indicates that environmental effects are already at work 650 Myr after the Big Bang.