61 research outputs found
The evolution of Radio Loud Quasar host galaxies: AO observations at z = 3
We report on ESO--VLT adaptive optics imaging of one radio-loud quasar at z
3. In spite of the large distance of the object we are able to detect
its surrounding extended nebulosity the properties of which are consistent with
an underlying massive galaxy of M --27 and effective radius R =
7 kpc. As far as we know this is the clearest detection of a radio loud quasar
host at high redshift. The host luminosity is indicative of the existence of
massive spheroids even at this early cosmic epoch. The host luminosity is about
1 magnitude fainter than the expected value based on the average trend of the
host galaxies of RLQ at lower redshift. The result, which however is based on a
single object, suggests that at z 3 there is a deviation from a
luminosity--redshift dependence regulated only by passive evolution.Comment: 6 pages, 3 figures, TeX uses elsart.cls, from workshop "QSO Host
Galaxies: Evolution and Environment" (Univ. Leiden, Aug. 22-26, 2005
Theoretical analysis of neutron scattering results for quasi-two dimensional ferromagnets
A theoretical study has been carried out to analyse the available results
from the inelastic neutron scattering experiment performed on a quasi-two
dimensional spin-1/2 ferromagnetic material . Our formalism is based
on a conventional semi-classical like treatment involving a model of an ideal
gas of vortices/anti-vortices corresponding to an anisotropic XY Heisenberg
ferromagnet on a square lattice. The results for dynamical structure functions
for our model corresponding to spin-1/2, show occurrence of negative values in
a large range of energy transfer even encompassing the experimental range, when
convoluted with a realistic spectral window function. This result indicates
failure of the conventional theoretical framework to be applicable to the
experimental situation corresponding to low spin systems. A full quantum
formalism seems essential for treating such systems.Comment: 16 pages, 6 figures, 1 Table Submitted for publicatio
Continuous observations of the surface energy budget and meteorology over the Arctic sea ice during MOSAiC
The Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) was a yearlong expedition supported by the icebreaker R/V Polarstern, following the Transpolar Drift from October 2019 to October 2020. The campaign documented an annual cycle of physical, biological, and chemical processes impacting the atmosphere-ice-ocean system. Of central importance were measurements of the thermodynamic and dynamic evolution of the sea ice. A multi-agency international team led by the University of Colorado/CIRES and NOAA-PSL observed meteorology and surface-atmosphere energy exchanges, including radiation; turbulent momentum flux; turbulent latent and sensible heat flux; and snow conductive flux. There were four stations on the ice, a 10 m micrometeorological tower paired with a 23/30 m mast and radiation station and three autonomous Atmospheric Surface Flux Stations. Collectively, the four stations acquired ~928 days of data. This manuscript documents the acquisition and post-processing of those measurements and provides a guide for researchers to access and use the data products
Gendered self-views across 62 countries: a test of competing models
Social role theory posits that binary gender gaps in agency and communion should be larger in less egalitarian countries, reflecting these countries’ more pronounced sex-based power divisions. Conversely, evolutionary and self-construal theorists suggest that gender gaps in agency and communion should be larger in more egalitarian countries, reflecting the greater autonomy support and flexible self-construction processes present in these countries. Using data from 62 countries (N = 28,640), we examine binary gender gaps in agentic and communal self-views as a function of country-level objective gender equality (the Global Gender Gap Index) and subjective distributions of social power (the Power Distance Index). Findings show that in more egalitarian countries, gender gaps in agency are smaller and gender gaps in communality are larger. These patterns are driven primarily by cross-country differences in men’s self-views and by the Power Distance Index (PDI) more robustly than the Global Gender Gap Index (GGGI). We consider possible causes and implications of these findings
A new statistical approach for generating meaningful particle size distributions from aberration corrected STEM-HAADF images of supported metal catalysts
Metal oxides
This article details the preparation, catalytic activity, computer modeling, and design of heterogeneous oxide catalysts
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