4,121 research outputs found
Cross border Classical Swine Fever control: Improving Dutch and German crisis management systems by an integrated public-private approach
The objective of this research approach is to analyse in which ways crisis management measures against Classical Swine Fever (CSF) can be improved by a public private cross border model. A core activity contains the analysis of information and communication systems: In a case study it has been empirically analysed if a sufficient supply of public and private information enables crisis managers at both sides of the Dutch-German border area to take decisions about CSF control more efficient. At the end of this approach a new crisis management model had been developed. One of the most important aspects thereby is the assessment of data: (1) within private quality management systems in normal times according to the benefit for public management tasks in times of crisis and (2) within public crisis management systems according to the benefit for cross-border CSF-control activities. To this effect two different methodological approaches have been combined within the model: (1) a method to identify and illustrate public actors and their options in crisis management decision making and (2) a system of communication and information exchange between public and private as well as Dutch and German actors (engage& exchange model) which permit to collect and to evaluate data in addition for a predefined time period are activated
Prospects for CW and LP operation of the European XFEL in hard X-ray regime
The European XFEL will operate nominally at 17.5 GeV in SP (short pulse) mode
with 0.65 ms long bunch train and 10 Hz repetition rate. A possible upgrade of
the linac to CW (continuous wave) or LP (long pulse) modes with a corresponding
reduction of electron beam energy is under discussion since many years. Recent
successes in the dedicated R&D program allow to forecast a technical
feasibility of such an upgrade in the foreseeable future. One of the challenges
is to provide sub-Angstrom FEL operation in CW and LP modes. In this paper we
perform a preliminary analysis of a possible operation of the European XFEL in
the hard X-ray regime in CW and LP modes with the energies of 7 GeV and 10 GeV,
respectively. We consider lasing in the baseline XFEL undulator as well as in a
new undulator with a reduced period. We show that, with reasonable requirements
on electron beam quality, lasing on the fundamental will be possible in
sub-Angstrom regime. As an option for generation of brilliant photon beams at
short wavelengths we also consider harmonic lasing that has recently attracted
a significant attention
XMM-Newton observations of the eastern jet of SS433
The radio supernova remnant W50 hosts at its center the peculiar galactic
X-ray binary SS 433. It shows a central spherical structure with two `ears'
which are supposed to be formed by the interaction of the precessing jets of SS
433 with the supernova shell. In two pointings in September/October 2004 for 30
ks each the eastern jet of SS 433 was observed with XMM-Newton to study the
outermost parts of the `ear' and the X-ray bright emission region about 35
arcmin from SS 433. The spectra consist of two components: a non-thermal power
law with photon index \Gamma ~ 2.17+/-0.02 and a thermal component at a typical
temperature of kT ~ 0.3 keV. The X-ray emission seems to fill the whole
interior region of the radio remnant W50. The jet terminates in the eastern
`ear' in a ring-like terminal shock which indicates a flow with a kind of
hollow-cone morphology. The spatial coincidence of X-ray and radio emission
suggests physical conditions similar to those found at the outer shocks of
ordinary supernova remnants. The bright emission region closer to SS 433
radiates non-thermally in a spatially well confined geometry at higher X-ray
energies. At soft X-rays the shape of the region gets blurred, centered on the
hard lenticular emission. The shape of this region and the bend in the jet
propagation direction might be caused by the interaction of a re-collimated jet
with the outer, non homogeneous interstellar matter distribution. The physical
conditions leading to the re-collimation of the jet and the peculiar emission
morphology are far from being understood and require deeper observations as
well as a detailed modeling of the interaction of a jet with its surroundings.Comment: 10 pages, 8 figures, to appear in A&
Temperature Dependence of the Cu(2) NQR Line Width in YBaCuO
Systematic measurements of the Cu(2) NQR line width were performed in
underdoped YBaCuO samples over the temperature range 4.2 K
K. It was shown that the copper NQR line width monotonically increases
upon lowering temperature in the below-critical region, resembling temperature
behavior of the superconducting gap. The observed dependence is explained by
the fact that the energy of a condensate of sliding charge-current states of
the charge-density-wave type depends on the phase of order parameter.
Calculations show that this dependence appears only at . Quantitative
estimates of the line broadening at agree with the measurement results.Comment: 4 pages, 2 figure
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