26,018 research outputs found
Women in the 2010 Olympic and Paralympic Games: An Analysis of Participation, Leadership, and Media Opportunities
This report is the third in the series that follows the progress of women in the Olympic and Paralympic movement. The report provides the most accurate, comprehensive, and up-to-date examination of the participation trends among female Olympic and Paralympic athletes and the hiring trends of Olympic and Paralympic governing bodies with respect to the number of women who hold leadership positions in these organizations. The report also looks at newspaper and internet coverage of the 2010 Olympic and Paralympic Winter Games
Periodic Modulations in an X-ray Flare from Sagittarius A*
We present the highly significant detection of a quasi-periodic flux
modulation with a period of 22.2 min seen in the X-ray data of the Sgr A* flare
of 2004 August 31. This flaring event, which lasted a total of about three
hours, was detected simultaneously by EPIC on XMM-Newton and the NICMOS
near-infrared camera on the HST. Given the inherent difficulty in, and the lack
of readily available methods for quantifying the probability of a periodic
signal detected over only several cycles in a data set where red noise can be
important, we developed a general method for quantifying the likelihood that
such a modulation is indeed intrinsic to the source and does not arise from
background fluctuations. We here describe this Monte Carlo based method, and
discuss the results obtained by its application to a other XMM-Newton data
sets. Under the simplest hypothesis that we witnessed a transient event that
evolved, peaked and decayed near the marginally stable orbit of the
supermassive black hole, this result implies that for a mass of 3.5 x 10^{6}
Msun, the central object must have an angular momentum corresponding to a spin
parameter of a=0.22.Comment: 4 pages, 6 figures, submitted to ApJ
The Dawes Review 1: Kinematic studies of star-forming galaxies across cosmic time
The last seven years have seen an explosion in the number of Integral Field
galaxy surveys, obtaining resolved 2D spectroscopy, especially at
high-redshift. These have taken advantage of the mature capabilities of 8-10 m
class telescopes and the development of associated technology such as AO.
Surveys have leveraged both high spectroscopic resolution enabling internal
velocity measurements and high spatial resolution from AO techniques and sites
with excellent natural seeing. For the first time, we have been able to glimpse
the kinematic state of matter in young, assembling star-forming galaxies and
learn detailed astrophysical information about the physical processes and
compare their kinematic scaling relations with those in the local Universe.
Observers have measured disc galaxy rotation, merger signatures, and
turbulence-enhanced velocity dispersions of gas-rich discs. Theorists have
interpreted kinematic signatures of galaxies in a variety of ways (rotation,
merging, outflows, and feedback) and attempted to discuss evolution vs.
theoretical models and relate it to the evolution in galaxy morphology. A key
point that has emerged from this activity is that substantial fractions of
high-redshift galaxies have regular kinematic morphologies despite irregular
photometric morphologies and this is likely due to the presence of a large
number of highly gas-rich discs. There has not yet been a review of this
burgeoning topic. In this first Dawes review, I will discuss the extensive
kinematic surveys that have been done and the physical models that have arisen
for young galaxies at high-redshift.Comment: 51 pages, 34,000 words, 16 figures. A few minor corrections have been
made to the journal version. High-resolution PDF and iPad optimised ePUB
versions available from http://astronomy.swin.edu.au/karl/dawe
Detecting Extrasolar Planets with Integral Field Spectroscopy
Observations of extrasolar planets using Integral Field Spectroscopy (IFS),
if coupled with an extreme Adaptive Optics system and analyzed with a
Simultaneous Differential Imaging technique (SDI), are a powerful tool to
detect and characterize extrasolar planets directly; they enhance the signal of
the planet and, at the same time, reduces the impact of stellar light and
consequently important noise sources like speckles. In order to verify the
efficiency of such a technique, we developed a simulation code able to test the
capabilities of this IFS-SDI technique for different kinds of planets and
telescopes, modelling the atmospheric and instrumental noise sources. The first
results obtained by the simulations show that many significant extrasolar
planet detections are indeed possible using the present 8m-class telescopes
within a few hours of exposure time. The procedure adopted to simulate IFS
observations is presented here in detail, explaining in particular how we
obtain estimates of the speckle noise, Adaptive Optics corrections, specific
instrumental features, and how we test the efficiency of the SDI technique to
increase the signal-to-noise ratio of the planet detection. The most important
results achieved by simulations of various objects, from 1 M_J to brown dwarfs
of 30 M_J, for observations with an 8 meter telescope, are then presented and
discussed.Comment: 60 pages, 37 figures, accepted in PASP, 4 Tables adde
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Developing Diplomats: Comparing Form and Culture Across Diplomatic Services, PRP 194
This study is a detailed and focused effort to broaden how we understand and conceptualize the recruitment, training, and development of professional diplomats in the twenty-first century. The goal is not to criticize processes in different countries, but to create a common foundation for comparing, learning, and even integrating training and career development models across nations.Public Affair
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