61,371 research outputs found
Runoff modelling in glacierized Central Asian catchments for present-day and future climate
A conceptual precipitation–runoff model was applied in five glacierized catchments in Central Asia. The model, which was first developed and applied in the Alps, works on a daily time step and yields good results in the more continental climate of the Tien Shan mountains for present-day climate conditions. Runoff scenarios for different climates (doubling of CO2) and glacierization conditions predict an increased flood risk as a first stage and a more complex picture after a complete glacier loss: a higher discharge during spring due to an earlier and more intense snowmelt is followed by a water deficiency in hot and dry summer periods. This unfavourable seasonal redistribution of the water supply has dramatic consequences for the Central Asian lowlands, which depend to a high degree on the glacier melt water for irrigation and already nowadays suffer from water shortages
Citizens without nations
To broach the question of whether citizenship could exist without (or beyond) community, this paper discusses genealogies of citizenship as membership that binds an individual to the community of birth (of the self or a parent). It is birthright as fraternity that blurs the boundary between citizenship and nationality. After briefly discussing recent critical studies on birthright citizenship (whether it is civic or ethnic or blood or soil) by Ayelet Shachar and Jacqueline Stevens, the paper discusses three critical genealogies of the relationship between birthright and citizenship by Max Weber, Hannah Arendt, and Michel Foucault. Although each provides a critical perspective into the question, Weber reduces citizenship to fraternity with nation and Arendt reduces citizenship to fraternity with the state. It is Foucault who illustrates racialization of fraternity as the connection between citizenship and nationality. Yet, since Foucault limits his genealogical investigations to the 18th and 19th centuries, a genealogy of fraternity of what he calls an immense biblical and Greek tradition remains for Derrida to articulate as a question of citizenship
Phonon lineshapes in the vortex state of the phonon-mediated superconductor YNiBC
We present an inelastic neutron scattering study of phonon lineshapes in the
vortex state of the type-II superconductor YNiBC. In a previous study
[Phys. Rev. Lett. \textbf{101}, 237002 (2008)] it was shown that certain
phonons exhibit a clear signature of the superconducting gap on
entering the superconducting state. Our interest was to find out whether or not
the lineshape of such phonons reflects the inhomogeneous nature of the vortex
state induced by a magnetic field smaller than the upper critical field
.We found that this is indeed the case because the observed phonon
lineshapes can be well described by a model considering the phonon as a local
probe of the spatial variation of the superconducting gap. We found that even
at , where the inter-vortex distance is less than \AA, the
phonon lineshape still shows evidence for a variation of the gap
Diamonds as timing detectors for MIP: The HADES proton-beam monitor and start detectors
This paper gives an overview of a recent development of measuring time of
flight of minimum-ionizing particles (MIP) with mono-crystalline diamond
detectors. The application in the HADES spectrometer as well as test results
obtained with proton beams are discussed.Comment: submitted to Nuclear Instruments and Methods
Study to investigate and evaluate means of optimizing the Ku-band combined radar/communication functions for the space shuttle
The Ku band radar system on the shuttle orbiter operates in both a search and a tracking mode, and its transmitter and antennas share time with the communication mode in the integrated system. The power allocation properties and the Costa subloop subcarrier tracking performance associated with the baseline digital phase shift implementation of the three channel orbiter Ku band modulator are discussed
Shape-induced phenomena in the finite size antiferromagnets
It is of common knowledge that the direction of easy axis in the finite-size
ferromagnetic sample is controlled by its shape. In the present paper we show
that a similar phenomenon should be observed in the compensated
antiferromagnets with strong magnetoelastic coupling. Destressing energy which
originates from the long-range magnetoelastic forces is analogous to
demagnetization energy in ferromagnetic materials and is responsible for the
formation of equilibrium domain structure and anisotropy of macroscopic
magnetic properties. In particular, crystal shape may be a source of additional
uniaxial magnetic anisotropy which removes degeneracy of antiferromagnetic
vector or artificial 4th order anisotropy in the case of a square cross-section
sample. In a special case of antiferromagnetic nanopillars shape-induced
anisotropy can be substantially enhanced due to lattice mismatch with the
substrate. These effects can be detected by the magnetic rotational torque and
antiferromagnetic resonance measurements.Comment: 7 pages, 5 figures, to appear in Phys. Rev. B, v.75, N17, 200
Observations of Subarcsecond Bright Dots in the Transition Region above Sunspots with the Interface Region Imaging Spectrograph
Observations with the Interface Region Imaging Spectrograph (IRIS) have
revealed numerous sub-arcsecond bright dots in the transition region above
sunspots. These bright dots are seen in the 1400\AA{} and 1330\AA{} slit-jaw
images. They are clearly present in all sunspots we investigated, mostly in the
penumbrae, but also occasionally in some umbrae and light bridges. The bright
dots in the penumbrae typically appear slightly elongated, with the two
dimensions being 300--600 km and 250--450 km, respectively. The long sides of
these dots are often nearly parallel to the bright filamentary structures in
the penumbrae but sometimes clearly deviate from the radial direction. Their
lifetimes are mostly less than one minute, although some dots last for a few
minutes or even longer. Their intensities are often a few times stronger than
the intensities of the surrounding environment in the slit-jaw images. About
half of the bright dots show apparent movement with speeds of
10--40~km~s in the radial direction. Spectra of a few bright dots
were obtained and the Si~{\sc{iv}}~1402.77\AA{} line profiles in these dots are
significantly broadened. The line intensity can be enhanced by one to two
orders of magnitude. Some relatively bright and long-lasting dots are also
observed in several passbands of the Atmospheric Imaging Assembly onboard the
Solar Dynamics Observatory, and they appear to be located at the bases of
loop-like structures. Many of these bright dots are likely associated with
small-scale energy release events at the transition region footpoints of
magnetic loops.Comment: 5 figures, will appear in ApJ
Upper limits on stray force noise for LISA
We have developed a torsion pendulum facility for LISA gravitational
reference sensor ground testing that allows us to put significant upper limits
on residual stray forces exerted by LISA-like position sensors on a
representative test mass and to characterize specific sources of disturbances
for LISA. We present here the details of the facility, the experimental
procedures used to maximize its sensitivity, and the techniques used to
characterize the pendulum itself that allowed us to reach a torque sensitivity
below 20 fNm /sqrt{Hz} from 0.3 to 10 mHz. We also discuss the implications of
the obtained results for LISA.Comment: To be published in Classical and Quantum Gravity, special issue on
Amaldi5 2003 conference proceedings (10 pages, 6 figures
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