Examinando por Autor "Kocevski, D. D."

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Acceso Abierto
Implications of Increased Central Mass Surface Densities for the Quenching of Low-mass Galaxies
(IOP Science Publishing, 2021-06-08) Guo, Y.; Carleton, T.; Bell, E. F.; Chen, Z.; Dekel, A.; Faber, S. M.; Giavalisco, M.; Kocevski, D. D.; Koekemoer, A. M.; Koo, D. C.; Kurczynski, P.; Lee, S. K.; Liu, F. S.; Papovich, C.; Pérez González, G.; National Science Foundation (NSF); National Aeronautics and Space Administration (NASA); National Research Foundation of Korea (NRF); Guo, Y. [0000-0003-2775-2002]; Carleton, T. [0000-0001-6650-2853]; Bell, E. F. [0000-0002-5564-9873]; Chen, Z. [0000-0002-2326-0476]; Dekel, A. [0000-0003-4174-0374]; Fabel, S. M. [0000-0003-4996-214X]; Giavalisco, M. [0000-0002-7831-8751]; Kocevski, D. D. [0000-0002-8360-3880]; Koekemoer, A. M. [0000-0002-6610-2048]; Koo, D. C. [0000-0003-3385-6799]; Kurczynski, P. [0000-0002-8816-5146]; Lee, S. K. [0000-0001-5342-8906]; Liu, F. S. [0000-0002-1064-1544]; Papovich, C. [0000-0001-7503-8482]; Pérez González, P. G. [0000-0003-4528-5639]
We use the Cosmic Assembly Deep Near-infrared Extragalactic Legacy Survey data to study the relationship between quenching and the stellar mass surface density within the central radius of 1 kpc (Σ1) of low-mass galaxies (stellar mass M* ≲ 109.5 M⊙) at 0.5 ≤ z < 1.5. Our sample is mass complete down to ∼109 M⊙ at 0.5 ≤ z < 1.0. We compare the mean Σ1 of star-forming galaxies (SFGs) and quenched galaxies (QGs) at the same redshift and M*. We find that low-mass QGs have a higher Σ1 than low-mass SFGs, similar to galaxies above 1010 M⊙. The difference of Σ1 between QGs and SFGs increases slightly with M* at M* ≲ 1010 M⊙ and decreases with M* at M* ≳ 1010 M⊙. The turnover mass is consistent with the mass where quenching mechanisms transition from internal to environmental quenching. At 0.5 ≤ z < 1.0, we find that Σ1 of galaxies increases by about 0.25 dex in the green valley (i.e., the transition region from star forming to fully quenched), regardless of their M*. Using the observed specific star formation rate gradient in the literature as a constraint, we estimate that the quenching timescale (i.e., time spent in the transition) of low-mass galaxies is a few (∼4) Gyr at 0.5 ≤ z < 1.0. The mechanisms responsible for quenching need to gradually quench star formation in an outside-in way, i.e., preferentially ceasing star formation in outskirts of galaxies while maintaining their central star formation to increase Σ1. An interesting and intriguing result is the similarity of the growth of Σ1 in the green valley between low-mass and massive galaxies, which suggests that the role of internal processes in quenching low-mass galaxies is a question worthy of further investigation.
Restringido
The structural properties of classical bulges and discs from z ∼ 2
(Oxford Academics: Oxford University Press, 2019-09-02) Dimauro, P.; Huertas Company, M.; Daddi, E.; Pérez González, P. G.; Bernardi, M.; Caro, F.; Cattaneo, A.; Häubler, B.; Kuchner, U.; Shankar, F.; Barro, G.; Buitrago, F.; Faber, S. M.; Kocevski, D. D.; Koekemoer, A. M.; Koo, D. C.; Mei, S.; Peletier, R.; Primack, J.; Rodríguez Puebla, A.; Salvato, M.; Tuccillo, D.; Ministerio de Economía y Competitividad (MINECO); Salvato, M. [https://orcid.org/0000-0001-7116-9303]; Buitrago, F. [https://orcid.org/0000-0002-2861-9812]; Daddi, E. [https://orcid.org/0000-0002-3331-9590]; Peletier, R. [https://orcid.org/0000-0001-7621-947X]; Huertas Company, M. [https://orcid.org/0000-0002-1416-8483]
We study the rest-frame optical mass–size relation of bulges and discs from z ∼ 2 to z ∼ 0 for a complete sample of massive galaxies in the CANDELS fields using two-component Sérsic models. Discs and star-forming galaxies follow similar mass–size relations. The mass–size relation of bulges is less steep than the one of quiescent galaxies (best-fitting slope of 0.7 for quiescent galaxies against 0.4 for bulges). We find little dependence of the structural properties of massive bulges and discs with the global morphology of galaxies (disc versus bulge dominated) and the star formation activity (star-forming versus quiescent). This result suggests similar bulge formation mechanisms for most massive galaxies and also that the formation of the bulge component does not significantly affect the disc structure. Our results pose a challenge to current cosmological models that predict distinct structural properties for stellar bulges arising from mergers and disc instabilities.