Statistics of the structure components in S0s: implications for bar induced secular evolution

The fractions and dimension of bars, rings and lenses are studied in the Near-IR S0 galaxy Survey (NIRS0S). We find evidence that multiple lenses in some barred S0s are related to bar resonances in a similar manner as the inner and outer rings, for which the outer/inner length ratio 2. Inner lenses in the non-barred galaxies normalized to galaxy diameter are clearly smaller than those in the barred systems. Interestingly, these small lenses in the non-barred galaxies have similar sizes as barlenses (lens-like structures embedded in a bar), and therefore might actually be barlenses in former barred galaxies, in which the outer, more elongated bar component, has been destroyed. We also find that fully developed inner lenses are on average a factor 1.3 larger than bars, whereas inner rings have similar sizes as bars. The fraction of inner lenses is found to be constant in all family classes (A, AB, B). Nuclear bars appear most frequently among the weakly barred (AB) galaxies, which is consistent with the theoretical models by Maciejewski & Athanassoula (2008). Similar sized bars as the nuclear bars were detected in seven 'non-barred' S0s. Galaxy luminosity does not uniquely define the sizes of bars or bar-related structures, neither is there any upper limit in galaxy luminosity for bar formation. Although all the family classes cover the same range of galaxy luminosity, the non-barred (A) galaxies are on average 0.6 mag brighter than the strongly barred (B) systems. Overall, our results are consistent with the idea that bars play an important role in the formation of the structure components of galaxies. The fact that multiple lenses are common in S0s, and that at least the inner lenses can have very old stellar populations, implies that the last destructive merger, or major gas accretion event, must have taken place at a fairly high redshift.Comment: 36 pages (include 13 figures, 11 tables). Accepted to MNRAS 2013 Jan 2

A Scale to Assess Student Perceptions of Academic Climates

Sandler and Hall (1986) define a chilly academic climate as the "... subtle ways women are treated differently — ways that communicate to women that they are not quite first-class citizens in the academic community" (p. 1). This paper describes the construction of a scale to assess university students' perceptions of the chilly climate. An initial pool of 123 items was refined based on statistical analyses of the responses of 192 students to produce a 28-item Perceived Chilly Climate Scale (PCCS). Factor analysis identified five factors: Climate Students Hear About; Sexist Treatment; Climate Students Experience Personally; Classroom Climate; and Safety. To investigate further the reliability and validity of the scale, the PCCS, an Alienation Scale (Dean, 1961) and the Marlowe-Crowne Social Desirability Scale (Reynolds, 1982) responses were gathered from 327 students. As expected, the PCCS was significantly related to alienation but unrelated to socially desirable responding. Additional evidence supporting the reliability and validity of the PCCS is presented.Pour Sandler et Hall (1986), le climat glacial qui règne dans les universités correspond à des moyens subtils de faire comprendre aux femmes qu'elles ne sont pas tout à fait des citoyennes de première classe dans le milieu universitaire. Cet article décrit la construction d'une échelle pour évaluer la perception des étudiants universitaires du climat glacial. Des analyses statistiques appliquées aux réponses fournies par 192 étudiants concernant un ensemble initial de 123 énoncés ont permis la création d'une échelle de Perception du Climat Glacial (Perceived Chilly Climate Scale; PCCS) composée de 28 énoncés. Une analyse factorielle a identifié cinq facteurs qui sont: le climat dont les étudiants entendent parler; le traitement sexiste; le climat que les étudiants éprouvent personnellement; le climat en classe; et la sécurité. Pour analyser la fidélité et la validité de l'échelle, nous avons demandé à 327 étudiants de compléter le PCCS, une échelle de régression (Dean, 1961) et le Marlowe-Crowne Social Desirability Scale (Reynolds, 1982). Comme prévu, les réponses obtenues au PCCS étaient très proches de celles obtenues à l'échelle de régression mais pas du tout des réponses se rapportant à l'échelle de désirabilité sociale. D'autres évidences qui corroborent la fidélité et la validité du PCCS sont présentées

The Research Data Centre of the Centre for European Economic Research (ZEW-FDZ)

Das Zentrum für Europäische Wirtschaftsforschung (ZEW) in Mannheim stellt eine Reihe seiner Forschungsdatensätze externen Wissenschaftlern zur Verfügung. Das ZEW folgt damit den Empfehlungen der „Kommission zur Verbesserung der informationellen Infrastruktur zwischen Wissenschaft und Statistik“ und unterstützt so die Weiterentwicklung der empirischen Wirtschafts- und Sozialforschung. Im November 2012 ist das ZEW-FDZ vom Rat für Sozial und Wirtschaftsdaten (RatSWD) akkreditiert worden. Bei den im ZEW-FDZ angebotenen ZEW Forschungsdaten handelt es sich um Mikrodaten von ZEW Unternehmensbefragungen, ZEW Expertenbefragungen oder ZEW Personenbefragungen. Die Daten einiger ZEW-Befragungen werden externen Wissenschaftlern in einer faktisch anonymisierten Form als Scientific-Use-Files zur Verfügung gestellt. Neben der Nutzung der Scientific-Use-Files können externe Forscher einen Antrag auf Nutzung von formal anonymisierten ZEW-Daten stellen, mit denen sie in den FDZ-Räumen des ZEW arbeiten dürfen. Formal anonymisiert bedeutet, dass die Datensätze weder Namen noch Adressen, aber ansonsten alle Originalangaben der Befragten enthalten. Die formal anonymisierten Daten befinden sich dazu auf einem Stand-alone-Rechner ohne Netzwerkanbindung, von dem keine Daten heruntergeladen werden können. Für das Mannheimer Innovationspanel (MIP) wurden zudem absolut anonymisierte Education-Use-Files für die Nutzung in der Lehre erstellt. Das ZEW-FDZ schließt an die bisherige Praxis des ZEW an, eigene Erhebungsdaten an externe Wissenschaftler weiterzugeben. Vor dem Start des ZEW-FDZ im Januar 2013, stellte das ZEW etwa 280 Wissenschaftlern vom ZEW erhobene Forschungsdaten zur Verfügung; die meisten sind Nutzer des Mannheimer Innovationspanels (250). Das ZEW wird sein Datenangebot für externe Wissenschaftler laufend erweitern. Dies gilt auch für Daten zukünftiger Erhebunge

Implications for the origin of dwarf early-type galaxies: a detailed look at the isolated rotating dwarf early-type galaxy CG 611, with ramifications for the Fundamental Plane's (S_K)^2 kinematic scaling and the spin-ellipticity diagram

Selected from a sample of nine, isolated, dwarf early-type galaxies (ETGs) having the same range of kinematic properties as dwarf ETGs in clusters, we use CG 611 (LEDA 2108986) to address the Nature versus Nurture debate regarding the formation of dwarf ETGs. The presence of faint disk structures and rotation within some cluster dwarf ETGs has often been heralded as evidence that they were once late-type spiral or dwarf irregular galaxies prior to experiencing a cluster-induced transformation into an ETG. However, CG 611 also contains significant stellar rotation (~20 km/s) over its inner half light radius, R_(e,maj)=0.71 kpc, and its stellar structure and kinematics resemble those of cluster ETGs. In addition to hosting a faint young nuclear spiral within a possible intermediate-scale stellar disk, CG 611 has accreted an intermediate-scale, counter-rotating gas disk. It is therefore apparent that dwarf ETGs can be built by accretion events, as opposed to disk-stripping scenarios. We go on to discuss how both dwarf and ordinary ETGs with intermediate-scale disks, whether under (de)construction or not, are not fully represented by the kinematic scaling S_0.5=sqrt{ 0.5(V_rot)^2 + sigma^2 }, and we also introduce a modified spin-ellipticity diagram, lambda(R)-epsilon(R), with the potential to track galaxies with such disks.Comment: 15 pages (includes 9 figures and an extensive 2+ page reference list

LEDA 074886: A remarkable rectangular-looking galaxy

We report the discovery of an interesting and rare, rectangular-shaped galaxy. At a distance of 21 Mpc, the dwarf galaxy LEDA 074886 has an absolute R-band magnitude of -17.3 mag. Adding to this galaxy's intrigue is the presence of an embedded, edge-on stellar disk (of extent 2R_{e,disk} = 12 arcsec = 1.2 kpc) for which Forbes et al. reported V_rot/sigma ~ 1.4. We speculate that this galaxy may be the remnant of two (nearly edge-one) merged disk galaxies in which the initial gas was driven inward and subsequently formed the inner disk, while the stars at larger radii effectively experienced a dissipationless merger event resulting in this `emerald cut galaxy' having very boxy isophotes with a_4/a = -0.05 to -0.08 from 3 to 5 kpc. This galaxy suggests that knowledge from simulations of both `wet' and `dry' galaxy mergers may need to be combined to properly understand the various paths that galaxy evolution can take, with a particular relevance to blue elliptical galaxies.Comment: To appear in ApJ. Six pages including references and figure

An energy-momentum consistent time integration scheme based on a mixed framework for non-linear electro-elastodynamics

The objective of the present work is the introduction of new mixed variational principles for EM time integrators in electromechanics, hence bridging the gap between the previous work presented by the authors in References [11] and [1], opening up the possibility to a variety of new Finite Element implementations

Why Are Alkali Halide Solid Surfaces Not Wetted By Their Own Melt?

Alkali halide (100) crystal surfaces are anomalous, being very poorly wetted by their own melt at the triple point. We present extensive simulations for NaCl, followed by calculations of the solid-vapor, solid-liquid, and liquid-vapor free energies showing that solid NaCl(100) is a nonmelting surface, and that its full behavior can quantitatively be accounted for within a simple Born-Meyer-Huggins-Fumi-Tosi model potential. The incomplete wetting is traced to the conspiracy of three factors: surface anharmonicities stabilizing the solid surface; a large density jump causing bad liquid-solid adhesion; incipient NaCl molecular correlations destabilizing the liquid surface. The latter is pursued in detail, and it is shown that surface short-range charge order acts to raise the surface tension because incipient NaCl molecular formation anomalously reduces the surface entropy of liquid NaCl much below that of solid NaCl(100).Comment: 4 pages, 3 figure

The AIMSS Project, III : the stellar populations of compact stellar systems

In recent years, a growing zoo of compact stellar systems (CSSs) have been found whose physical properties (mass, size, velocity dispersion) place them between classical globular clusters (GCs) and true galaxies, leading to debates about their nature. Here we present results using a so far underutilized discriminant, their stellar population properties. Based on new spectroscopy from 8-10m telescopes, we derive ages, metallicities, and [α/Fe] of 29 CSSs. These range from GCs with sizes of merely a few parsec to compact ellipticals (cEs) larger than M32. Together with a literature compilation, this provides a panoramic view of the stellar population characteristics of early-type systems. We find that the CSSs are predominantly more metal rich than typical galaxies at the same stellar mass. At high mass, the cEs depart from the mass-metallicity relation of massive early-type galaxies, which forms a continuous sequence with dwarf galaxies. At lower mass, the metallicity distribution of ultracompact dwarfs (UCDs) changes at a few times 10^7 M⊙, which roughly coincides with the mass where luminosity function arguments previously suggested the GC population ends. The highest metallicities in CSSs are paralleled only by those of dwarf galaxy nuclei and the central parts of massive early types. These findings can be interpreted as CSSs previously being more massive and undergoing tidal interactions to obtain their current mass and compact size. Such an interpretation is supported by CSSs with direct evidence for tidal stripping, and by an examination of the CSS internal escape velocities.Fil: Janz, Joachin. Swinburne University; AustraliaFil: Norris, Mark A.. Gobierno de la Republica Federal de Alemania. Max Planck Institut Fur Astrophysik; AlemaniaFil: Forbes, Duncan A.. Swinburne University; AustraliaFil: Huxor, Avon. Universität Heidelberg; AlemaniaFil: Romanowsky, Aaron. San José State University; Estados UnidosFil: Frank, Matthias. Universität Heidelberg; AlemaniaFil: Escudero, Carlos Gabriel. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Faifer, Favio Raúl. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Forte, Juan Carlos. Gobierno de la Ciudad de Buenos Aires. Secretaria de Cultura. Subsecretaria de Patrimonio Cultural. Planetario ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kannappan, Sheila J.. University of North Carolina; Estados UnidosFil: Maraston, Claudia. Institute of Cosmology snd Gravitation; Estados UnidosFil: Brodie, Jean. University of California; Estados UnidosFil: Strader, Jay. Michigan State University; Estados UnidosFil: Thompson, Bradley. San José State University; Estados Unido