Examinando por Autor "Peletier, R."

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Acceso Abierto
Disc galaxy resolved in H I absorption against the radio lobe of 3C 433: Case study for future surveys.
(EDP Sciences, 2020-11-05) Morgantini, R.; Emonts, B. H. C.; Villar Martín, M.; Oosterloo, T.; Peletier, R.; European Commission (EC); Agencia Estatal de Investigación (AEI); National Aeronautics and Space Administration (NASA); 0000-0003-4989-3316; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The neutral atomic gas content of galaxies is usually studied in the HI 21 cm emission line of hydrogen. However, as we go to higher redshifts, owing to the weak strength of the transition, we need very deep integrations to detect HI emission. The HI absorption does not suffer from this dependence on distance as long as there is a sufficiently bright radio source to provide the background continuum. However, resolved HI absorption studies of galaxies are rare. We report one such rare study of resolved HI absorption against the radio galaxy 3C 433 at z=0.101, detected with the Very Large Array. The absorption was known from single-dish observations, but owing to the higher spatial resolution of our data, we find that the absorber is located against the southern lobe of the radio galaxy. The resolved kinematics shows that the absorber has regular kinematics with an HI mass less than or similar to 3.4x10(8) M-circle dot for T-spin=100 K. We also present deep optical continuum observations and H alpha observations from the Gran Telescopio CANARIAS (GTC), which reveal that the absorber is likely to be a faint disc galaxy in the same environment as 3C 433, with a stellar mass of similar to 10(10) M-circle dot and a star-formation rate of 0.15 M-circle dot yr(-1) or less. Considering its HI mass, HI column density, stellar mass, and star-formation rate, this galaxy lies well below the main sequence of star forming galaxies. Its HI mass is lower than the galaxies studied in HI emission at z similar to 0.1. Our GTC imaging has revealed, furthermore, interesting alignments between H alpha and radio synchrotron emission in the HI companion and in the host galaxy of the active galactic nucleus as well as in the circumgalactic medium in between. This suggests that the shock ionization of gas by the propagating radio source may happen across a scale spanning many tens of kpc. Overall, our work supports the potential of studying the HI content in galaxies via absorption in the case of a fortuitous alignment with an extended radio continuum source. This approach may allow us to trace galaxies with low HI masses which would otherwise be missed by deep HI emission surveys. In conjunction with the deep all-sky optical surveys, the current and forthcoming blind HI surveys with the Square Kilometre Array (SKA) pathfinder facilities will be able to detect many such systems, though they may not be able to resolve the HI absorption spatially. Phase 1 of the SKA, with its sub-arcsecond resolution and high sensitivity, will be all the more able to resolve the absorption in such systems.
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.