7,296 research outputs found
Book review: campaign communication and political marketing
James Moran reviews an extensively well-researched and thorough book dealing with every level and stage of political campaigning
The EU-Arab Summit: A chance to reset relations with the Arab world? CEPS Commentary, 14 February 2019
Leaders of the 50 countries that comprise the EU and the Arab League, together with the European Institutions, are set to meet in Egypt’s Sharm el Sheikh on 24-25th February in an unprecedented summit encounter. Chaired by Presidents Abdel Fatah El-Sisi and Donald Tusk, the event marks the first time these close neighbours have come together in this format. As such, this is something of a breakthrough, although there is a risk of failure
The structure of the accretion disk in NGC 4258 derived from observations of its water vapor masers
A wealth of new information about the structure of the maser disk in NGC 4258
has been obtained from a series of 18 VLBA observations spanning three years,
as well as from 32 additional epochs of spectral monitoring data from 1994 to
the present, acquired with the VLA, Effelsberg, and GBT. The warp of the disk
has been defined precisely. The thickness of the maser disk has been measured
to be 12 microarcseconds (FWHM), which is slightly smaller than previously
quoted upper limits. Under the assumption that the masers trace the true
vertical distribution of material in the disk, from the condition of
hydrostatic equilibrium the sound speed is 1.5 km/s, corresponding to a thermal
temperature of 600K. The accelerations of the high velocity maser components
have been accurately measured for many features on both the blue and red side
of the spectrum. The azimuthal offsets of these masers from the midline (the
line through the disk in the plane of the sky) and derived projected offsets
from the midline based on the warp model correspond well with the measured
offsets. This result suggests that the masers are well described as discrete
clumps of masing gas, which accurately trace the Keplerian motion of the disk.
However, we have continued to search for evidence of apparent motions caused by
``phase effects.'' This work provides the foundation for refining the estimate
of the distance to NGC 4258 through measurements of feature acceleration and
proper motion. The refined estimate of this distance is expected to be
announced in the near future.Comment: 8 pages, 5 figures, to appear in proceedings of IAU Symposium 242
"Astrophysical Masers and their Environments", held in Alice Springs, March
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No longer a new kid on the block - China in the Middle East. CEPS Commentary, 29 November 2017
Given China’s growing role in the complex security dynamics in the Middle East and North Africa,
the EU should intensify its dialogue and, where interests coincide, joint action with Beijing
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