5,754 research outputs found

    Adaptive optics near-IR imaging of NGC2992 - unveiling core structures related to radio figure-8 loops

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    We present near-IR adaptive optics, VLA radio and HST optical imaging of the nearby Seyfert galaxy NGC2992. Spiral structure and an extension to the West are traced down to the core region at the limiting resolution of our near-IR images. A faint, diffuse loop of near-IR and radio emission is also observed to the north, embedded within the prominent 2 arcsec radio loop previously observed to the northwest. Near-IR color maps, and CO narrowband imaging, are then used to identify which regions may not be purely reddened stellar populations. Our new data provide evidence that the VLA radio-loop morphology in the shape of a figure-8 represents two components superimposed: 1) outflow bubbles out of the plane of the disk, coincident with the extended emission line region (EELR); 2) star formation along the spiral arm within the galaxy disk and through the dust lane. The near-IR continuum emission associated with the outflowing radio bubbles suggest that the radio loops are driven by the active nucleus.Comment: 10 pages, 9 figures, accepted in MNRA

    Trends in women's participation at the meetings of the Association for Behavior Analysis: 1975-2005

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    We examined women's participation, relative to men's, at the annual meetings of the Association for Behavior Analysis (ABA) between 1975 and 2005. Among our findings are upward trends in female presenters across formats (e.g., posters), types of authorship (e.g., first authors), and specialty areas (e.g., autism). Where women have attained parity, however, they are still often underrepresented, given their percentage of membership. Women also participate less than men as sole and invited authors and discussants and in the domains of basic research and conceptual analysis, but participate more than men in the applied domain. Data from the Journal of the Experimental Analysis of Behavior and the Journal of Applied Behavior Analysis show parallel but delayed trends toward parity in basic and applied research, whereas data from The Behavior Analyst show only modest gains in the conceptual domain. We discuss the gender disparities in ABA's more prestigious categories of participation (e.g., invited addresses) and across its content domains, as well as in science in general, and the role of social and cultural factors in producing the disparities and how behavior analysts might aid in correcting them

    Adolescents\u27 Attitudes and Intentions to Use a Smartphone App to Promote Safe Driving

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    Purpose Designing effective driving safety interventions is imperative as traffic crashes are the leading cause of injury and death for adolescents. Using concepts from the Integrated Behavioral Model, we investigated adolescents\u27 attitudes and intentions towards engaging in safe driving practices and using smartphone-based driving safety technology. Methods Two-hundred and seven adolescents aged 14–18 (M = 16.1, SD = 0.8) completed a safe driving survey. A path model testing the associations between individual scores of attitudes, perceived norms, and perceived behavioral control with intentions controlling for demographic covariates was conducted. Results Greater intentions to drive safely was associated with greater perceived norms from family and peers (β = 0.75, p \u3c .001) and perceived capability (β = 0.19, p \u3c .001) to drive safely. Greater intentions to adopt a driving safety app was associated with greater perceived norms from family and peers (β = 0.29, p = .007). Females reported greater intentions to adopt a driving safety app than males (β = −0.15, p = .044). Conclusions Assessing attitudes and perceptions provides further understanding of what behavioral constructs are important for the development of adolescent driver safety interventions. Experimental research targeting and modifying behavior constructs is warranted

    Emission-Line Imaging of QSOs with High Resolution

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    We report the first detection of emission-line gas within the host galaxies of high-redshift quasi-stellar objects (QSOs). This was done using narrowband imaging at the redshifted wavelengths of [O III] and Hα, using the PUEO adaptive optics camera of the Canada-France-Hawaii Telescope. The QSOs are all radio-quiet or very compact radio sources. In all five observed QSOs, which have redshifts 0.9 to 2.4, we find extended line emission that lies within 05 (a few kiloparsecs) of the nucleus. The emission (redshifted) equivalent widths range from 35 to 300 A. Where there is radio structure, the line emission is aligned with it. We also report on continuum fluxes and possible companions. Two of the QSOs are very red and have high resolved continuum flux

    Signatures of extended discs and outflows in the circumgalactic medium using the Q0107 quasar triplet

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    We use H I absorption along the lines-of-sight to the Q0107 quasar triplet in order to model potential disc and outflow structures in the circumgalactic medium of intervening galaxies at z ≲ 1, as well as the intergalactic medium on scales of up to a few virial radii. We consider a sample of twelve isolated galaxies in the Q0107 field with position angles and inclinations measured from HST imaging as well as redshifts from our spectroscopic surveys, alongside 27 detected Ly α absorbers within 500 km s−1 of these galaxies. Building on previous work showing increased incidence of absorption close to the projected major and minor axes, we use model rotating discs and bi-conical outflows in attempting to reproduce the observed absorption. Requiring these models to match absorption in multiple lines-of-sight provides additional constraints over single-sightline observations. We identify four possible outflows with velocities ∼100 km s−1, two of which extend to or beyond the virial radius, with a variety of opening angles. Two galaxies have nearby co-rotating absorbers with rotation velocities ≲ vvir, that may probe disc-like structures, and we can rule out a disc/outflow origin for a further ten absorbers. These indicate that outflowing and co-rotating structures can extend to large scales but are either not ubiquitous, or do not always produce detectable Ly α. In some cases, disc models are successful even close to the minor axis of the galaxy, and some of our model outflows exhibit wide opening angles. These results imply that purely geometrical cuts are not sufficient to distinguish between discs and outflows in single line-of-sight studies

    Modelling gas around galaxy pairs and groups using the Q0107 quasar triplet

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    We examine to what extent disc and outflow models can reproduce observations of H I gas within a few virial radii of galaxies in pairs and groups. Using highly sensitive HST/COS and FOS spectra of the Q0107 quasar triplet covering Ly α for z≲1, as well as a deep galaxy redshift survey including VIMOS, DEIMOS, GMOS, and MUSE data, we test simple disc and outflow models against the H I absorption along three lines-of-sight (separated by 200–500 kpc) through nine galaxy groups in this field. These can be compared with our previous results in which these models can often be fit to the absorption around isolated galaxies. Our models can reproduce ≈ 75 per cent of the 28 identified absorption components within 500 km s−1 of a group galaxy, so most of the H I around groups is consistent with a superposition of the CGM of the individual galaxies. Gas stripped in interactions between galaxies may be a plausible explanation for some of the remaining absorption, but neither the galaxy images nor the galaxy and absorber kinematics provide clear evidence of such stripped material, and these unexplained absorbers do not preferentially occur around close pairs of galaxies. We find H I column densities typically higher than at similar impact parameters around isolated galaxies (≈ 2.5σ), as well as more frequent detections of O VI than around isolated galaxies (30 per cent of sightlines to 7 per cent)
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