Browsing by Author "Ordenes-Briceno, Yasna"

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    A MUSE view of the core of the giant low-surface-brightness galaxy Malin 1
    (2024) Johnston, Evelyn J.; Galaz, Gaspar; Blana, Matias; Amram, Philippe; Boissier, Samuel; Eigenthaler, Paul; Epinat, Benoit; Junais; Ordenes-Briceno, Yasna; Puzia, Thomas; Weilbacher, Peter M.
    Aims. The central region of the giant low-surface-brightness galaxy Malin 1 has long been known to have a complex morphology, with evidence of a bulge, disc, and potentially a bar hosting asymmetric star formation. In this work, we use VLT/MUSE data to resolve the central region of Malin 1 in order to determine its structure. Methods. We used careful light profile fitting in every image slice of the datacube to create wavelength-dependent models of each morphological component, from which we were able to cleanly extract their spectra. We then used the kinematics and emission line properties from these spectra to better understand the nature of each component extracted from our model fitting. Results. We report the detection of a pair of distinct sources at the centre of this galaxy with a separation of similar to 1.05 '', which corresponds to a separation on sky of similar to 1.9 kpc. The radial velocity data of each object confirm that they both lie in the kinematic core of the galaxy. An analysis of the emission lines reveals that the central compact source is more consistent with being ionised through star formation and/or a LINER, while the off-centre compact source lies closer to the separation between star-forming galaxies and active galactic nuclei. Conclusions. This evidence suggests that the centre of Malin 1 hosts either a bar with asymmetric star formation or two distinct components. In the latter scenario, we propose two hypotheses for the nature of the off-centre compact source-it could either be a star-forming clump, containing one or more star clusters, that is in the process of falling into the core of the galaxy and eventually merging with the central nuclear star cluster, or it could be a clump of gas falling into the centre of the galaxy from either outside or from the disc and triggering star formation there.
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    BUDDI-MaNGA II: the star-formation histories of bulges and discs of S0s
    (OXFORD UNIV PRESS, 2022) Johnston, Evelyn J.; Haussler, Boris; Jegatheesan, Keerthana; Fraser-McKelvie, Amelia; Coccato, Lodovico; Cortesi, Arianna; Jaffe, Yara; Galaz, Gaspar; Mora, Marcelo; Ordenes-Briceno, Yasna
    Many processes have been proposed to explain the quenching of star formation in spiral galaxies and their transformation into S0s. These processes affect the bulge and disc in different ways, and so by isolating the bulge and disc spectra, we can look for these characteristic signatures. In this work, we used BUDDI to cleanly extract the spectra of the bulges and discs of 78 S0 galaxies in the MaNGA Survey. We compared the luminosity and mass weighted stellar populations of the bulges and discs, finding that bulges are generally older and more metal rich than their discs. When considering the mass and environment of each galaxy, we found that the galaxy stellar mass plays a more significant role on the formation of the bulges. Bulges in galaxies with masses >= 10(10) M-circle dot built up the majority of their mass rapidly early in their lifetimes, while those in lower mass galaxies formed over more extended time-scales and more recently. No clear difference was found in the formation or quenching processes of the discs as a function of galaxy environment. We conclude that more massive S0 galaxies formed through an inside-out scenario, where the bulge formed first and evolved passively while the disc underwent a more extended period of star formation. In lower mass S0s, the bulges and discs either formed together from the same material, or through an outside-in scenario. Our results therefore imply multiple formation mechanisms for S0 galaxies, the pathway of which is chiefly determined by a galaxy's current stellar mass.
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    Extending the evolution of the stellar mass-size relation at z ≤ 2 to low stellar mass galaxies from HFF and CANDELS
    (2021) Nedkova, Kalina, V; Haussler, Boris; Marchesini, Danilo; Dimauro, Paola; Brammer, Gabriel; Eigenthaler, Paul; Feinstein, Adina D.; Ferguson, Henry C.; Huertas-Company, Marc; Johnston, Evelyn J.; Kado-Fong, Erin; Kartaltepe, Jeyhan S.; Labbe, Ivo; Lange-Vagle, Daniel; Martis, Nicholas S.; McGrath, Elizabeth J.; Muzzin, Adam; Oesch, Pascal; Ordenes-Briceno, Yasna; Puzia, Thomas; Shipley, Heath, V; Simmons, Brooke D.; Skelton, Rosalind E.; Stefanon, Mauro; van der Wel, Arjen; Whitaker, Katherine E.
    We reliably extend the stellar mass-size relation over 0.2 <= z <= 2 to low stellar mass galaxies by combining the depth of Hubble Frontier Fields with the large volume covered by CANDELS. Galaxies are simultaneously modelled in multiple bands using the tools developed by the MegaMorph project, allowing robust size (i.e. half-light radius) estimates even for small, faint, and high redshift galaxies. We show that above 10(7) M-circle dot, star-forming galaxies are well represented by a single power law on the mass-size plane over our entire redshift range. Conversely, the stellar mass-size relation is steep for quiescent galaxies with stellar masses >= 10(10.3)M(circle dot) and flattens at lower masses, regardless of whether quiescence is selected based on star-formation activity, rest-frame colours, or structural characteristics. This flattening occurs at sizes of similar to 1 kpc at z <= 1. As a result, a double power law is preferred for the stellar mass-size relation of quiescent galaxies, at least above 10(7)M(circle dot). We find no strong redshift dependence in the slope of the relation of star-forming galaxies as well as of high mass quiescent galaxies. We also show that star-forming galaxies with stellar masses >= 10(9.5)M(circle dot) and quiescent galaxies with stellar masses >= 10(10.3)M(circle dot) have undergone significant size growth since z similar to 2, as expected; however, low mass galaxies have not. Finally, we supplement our data with predominantly quiescent dwarf galaxies from the core of the Fornax cluster, showing that the stellar mass-size relation is continuous below 10(7)M(circle dot), but a more complicated functional form is necessary to describe the relation.
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    Spectroscopy of NGC 4258 Globular Cluster Candidates: Membership Confirmation and Kinematics
    (2019) Gonzalez-Lopezlira, Rosa A.; Mayya, Y. D.; Loinard, Laurent; Alamo-Martinez, Karla; Heald, George; Georgiev, Iskren Y.; Ordenes-Briceno, Yasna; Lancon, Ariane; Lara-Lopez, Maritza A.; Lomeli-Nunez, Luis; Bruzual, Gustavo; Puzia, Thomas H.
    We present multiobject spectroscopic observations of 23 globular cluster candidates (GCCs) in the prototypical megamaser galaxy NGC 4258, carried out with the Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy instrument at the 10.4 m Gran Telescopio Canarias. The candidates have been selected based on the (u* - i') versus (i' - K-s) diagram, in the first application of the u*i'K-s, method to a spiral galaxy. In the spectroscopy presented here, 70% of the candidates are confirmed as globular clusters (GCs). Our results validate the efficiency of the u*i'K-s, method in the sparser GC systems of spirals, and given the downward correction to the total number of GCs, the agreement of the galaxy with the correlations between black hole mass and the total number and mass of GCs is actually improved. We find that the GCs, mostly metal-poor, corotate with the H I disk, even at large galactocentric distances.
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    The Relation between Globular Cluster Systems and Supermassive Black Holes in Spiral Galaxies. III. The Link to the M.-M * Correlation
    (2022) Gonzalez-Lopezlira, Rosa A.; Lomeli-Nunez, Luis; Ordenes-Briceno, Yasna; Loinard, Laurent; Gwyn, Stephen; Alamo-Martinez, Karla; Bruzual, Gustavo; Lancon, Ariane; Puzia, Thomas H.
    D We continue to explore the relationship between the total number of globular clusters (GCs), NGC, and the central black hole mass, M alpha, in spiral galaxies. We present here results for the Sab galaxies NGC 3368, NGC 4736 (M94), and NGC 4826 (M64), and the Sm galaxy NGC 4395. The GC candidate selection is based on the (u* - i cent) versus (i cent - Ks) color-color diagram, and i cent-band shape parameters. We determine the M alpha versus NGC correlation for these spirals, plus NGC 4258, NGC 253, M104, M81, M31, and the Milky Way. We also redetermine the correlation for the elliptical sample in Harris et al., with updated galaxy types from Sahu et al. Additionally, we derive the total stellar galaxy mass, M*, from its two-slope correlation with NGC, and fit M _ versus M* for both spirals and ellipticals. We obtain log M alpha. (1.01 +/- 0.13) log NGC for ellipticals, and log M alpha. (1.64 +/- 0.24) log NGC for latetype galaxies (LTGs). The linear M alpha versus NGC correlation in ellipticals could be due to statistical convergence through mergers, unlike the much steeper correlation for LTGs. However, in the M alpha versus total stellar mass (M*) parameter space, with M* derived from its correlation with NGC, M alpha. (1.48 +/- 0.18) log M* for ellipticals, and M alpha. (1.21 +/- 0.16) log M* for LTGs. The observed agreement between ellipticals and LTGs in this parameter space may imply that black holes and galaxies coevolve through calm accretion, active galactic nuclei feedback, and other secular processes.