The Diverse Nature of Optical Emission Lines in Brightest Cluster Galaxies: IFU Observations of the Central Kiloparsecs

We present integral field spectroscopy of the nebular line emission in a sample of 9 brightest cluster galaxies (BCGs). The sample was chosen to probe both cooling flow and non-cooling flow clusters, as well as a range of cluster X-ray luminosities. The line emission morphology and velocity gradients suggest a great diversity in the properties of the line emitting gas. While some BGCs show evidence for filamentary or patchy emission (Abell 1060, Abell 1668 and MKW3s), others have extended emission (Abell 1204, Abell 2199), while still others have centrally concentrated emission (Abell 2052). We examine diagnostic line ratios to determine the dominant ionization mechanisms in each galaxy. Most of the galaxies show regions with AGN-like spectra, however for two BCGs, Abell 1060 and Abell 1204, the emission line diagnostics suggest regions which can be described by the emission from young stellar populations. The diversity of emission line properties in our sample of BCGs suggests that the emission mechanism is not universal, with different ionization processes dominating different systems. Given this diversity, there is no evidence for a clear distinction of the emission line properties between cooling flow and non-cooling flow BCGs. It is not always cooling flow BCGs which show emission (or young stellar populations), and non-cooling flow BCGs which do not.Comment: 23 pages, 23 figures, accepted for publication in MNRAS. Full resolution images are online http://web.ipac.caltech.edu/staff/louis

A two-phase scenario for bulge assembly in ΛcDM cosmologies

The Astrophysical Journal 763.1 (2013): 26 reproduced by permission of the AASWe analyze and compare the bulges of a sample of L* spiral galaxies in hydrodynamical simulations in a cosmological context, using two different codes, P-DEVA and GASOLINE. The codes regulate star formation in very different ways, with P-DEVA simulations inputting low star formation efficiency under the assumption that feedback occurs on subgrid scales, while the GASOLINE simulations have feedback that drives large-scale outflows. In all cases, the marked knee shape in mass aggregation tracks, corresponding to the transition from an early phase of rapid mass assembly to a later slower one, separates the properties of two populations within the simulated bulges. The bulges analyzed show an important early starburst resulting from the collapse-like fast phase of mass assembly, followed by a second phase with lower star formation, driven by a variety of processes such as disk instabilities and/or mergers. Classifying bulge stellar particles identified at z = 0 into old and young according to these two phases, we found bulge stellar sub-populations with distinct kinematics, shapes, stellar ages, and metal contents. The young components are more oblate, generally smaller, more rotationally supported, with higher metallicity and less alpha-element enhanced than the old ones. These results are consistent with the current observational status of bulges, and provide an explanation for some apparently paradoxical observations, such as bulge rejuvenation and metal-content gradients observed. Our results suggest that bulges of L* galaxies will generically have two bulge populations that can be likened to classical and pseudo-bulges, with differences being in the relative proportions of the two, which may vary due to galaxy mass and specific mass accretion and merger histories.This work was partially supported by the MICINN (Spain) through the grants AYA2009-12792-C03-02 and AYA2009-12792-C03-03 from the PNAyA, as well as by the regional Madrid V PRICIT program through the ASTROMADRID network (CAM S2009/ESP-1496) and the “Supercomputación y e-Ciencia” Consolider-Ingenio CSD2007-0050 project

La Historia en la literatura española del siglo XIX

Editors literaris: José Manuel González Herrán, Marisa Sotelo Vázquez, Cristina Carbonell, Hazel Gold, Dolores Thion Soriano-Mollá, Blanca Ripoll Sintes i Jessica Cáliz MontesEste volumen recoge los frutos del VII Coloquio de la Sociedad de Literatura Española del Siglo XIX, celebrado en Barcelona entre el 22 y el 24 de octubre de 2014. El encuentro contó con una nutrida participación de especialistas procedentes de universidades españolas y de otros países europeos, norteamericanas y japonesas. Las cuarenta y siete ponencias se agrupan en seis secciones que abordan los diferentes aspectos de las relaciones entre la literatura y la historia desde el Romanticismo hasta el fin de siglo, así como la interacción de la historia con los distintos géneros literarios, especialmente la novela y el teatro, sin olvidar otras vertientes culturales como la prensa. Asimismo, se dedican sendas secciones monográficas a Benito Pérez Galdós y Emilia Pardo Bazán

A data base for Galaxy evolution modeling

This paper represents a collective effort to provide an extensive electronic database useful for the interpretation of galaxy properties