20 research outputs found
First results of the air shower experiment KASCADE
The main goals of the KASCADE (KArlsruhe Shower Core and Array DEtector)
experiment are the determination of the energy spectrum and elemental
composition of the charged cosmic rays in the energy range around the knee at
ca. 5 PeV. Due to the large number of measured observables per single shower a
variety of different approaches are applied to the data, preferably on an
event-by-event basis. First results are presented and the influence of the
high-energy interaction models underlying the analyses is discussed.Comment: 3 pages, 3 figures included, to appear in the TAUP 99 Proceedings,
Nucl. Phys. B (Proc. Suppl.), ed. by M. Froissart, J. Dumarchez and D.
Vignau
Electron, Muon, and Hadron Lateral Distributions Measured in Air-Showers by the KASCADE Experiment
Measurements of electron, muon, and hadron lateral distributions of extensive
air showers as recorded by the KASCADE experiment are presented. The data cover
the energy range from about 5x10^14 eV up to almost 10^17 eV and extend from
the inner core region to distances of 200 m. The electron and muon
distributions are corrected for mutual contaminations by taking into account
the detector properties in the experiment. All distributions are well described
by NKG-functions. The scale radii describing the electron and hadron data best
are approx. 30 m and 10 m, respectively. We discuss the correlation between
scale radii and `age' parameter as well as their dependence on shower size,
zenith angle, and particle energy threshold.Comment: 28 pages, 14 figures, Accepted for publication in Astroparticle
Physic
Progressive realism and the EU’s international actorness: towards a grand strategy?
The EU lacks a coherent strategy to guide its international actions.This is a problem that has been amply discussed in both academic and policy-making circles, but that remains to be fully addressed. The December 2013 European Council recognised the issue, and the EU High Representative Federica Mogherini is in charge of a strategic review that will lead to a global strategy by June 2016. Most arguments in favour of a grand strategy rely on utilitarian arguments that highlight the EU’s potential for a more efficient foreign policy. By linking a progressive realist approach to the importance of an EU grand strategy, this article intends to demonstrate the normative need for such a guiding document. As it will be argued, a grand strategy is a necessary step in the consolidation of the EU as a pluralist postnational polity that has in the fulfilment of its citizens’ interests its raison d’être
Cosmic ray physics around the knee with the KASCADE experiment
KASCADE (KArlsruhe Shower Core and Array DEtector) is a multidetector setup to observe the electromagnetic, muonic and hadronic air shower components simultaneously for the primary energy region around the knee. The large body of observables per single shower allows to follow the main aims of the experiment in analyses on an event-by-event basis, mainly: 1) slopes and structures of the primary energy spectrum; 2) the energy dependence of the chemical composition of the primaries; 3) tests of the air shower simulation tools underlying the analyses, in particular of the Monte Carlo generators based on different high-energy interaction models; 4) examinations of the air shower development in the atmosphere. Examples and results of different analysis methods are presented for the different
subjects
Towards a new image processing system at Wendelstein 7-X: From spatial calibration to characterization of thermal events
Wendelstein 7-X (W7-X) is the most advanced fusion experiment in the stellarator line and is aimed at proving that the stellarator concept is suitable for a fusion reactor. One of the most important issues for fusion reactors is the monitoring of plasma facing components when exposed to very high heat loads, through the use of visible and infrared (IR) cameras. In this paper, a new image processing system for the analysis of the strike lines on the inboard limiters from the first W7-X experimental campaign is presented. This system builds a model of the IR cameras through the use of spatial calibration techniques, helping to characterize the strike lines by using the information given by real spatial coordinates of each pixel. The characterization of the strike lines is made in terms of position, size, and shape, after projecting the camera image in a 2D grid which tries to preserve the curvilinear surface distances between points. The description of the strike-line shape is made by means of the Fourier Descriptors
Forward modeling of collective Thomson scattering for Wendelstein 7-X plasmas: Electrostatic approximation
In this paper, we present a method for numerical computation of collective Thomson scattering (CTS). We developed a forward model, eCTS, in the electrostatic approximation and benchmarked it against a full electromagnetic model. Differences between the electrostatic and the electromagnetic models are discussed. The sensitivity of the results to the ion temperature and the plasma composition is demonstrated. We integrated the model into the Bayesian data analysis framework Minerva and used it for the analysis of noisy synthetic data sets produced by a full electromagnetic model. It is shown that eCTS can be used for the inference of the bulk ion temperature. The model has been used to infer the bulk ion temperature from the first CTS measurements on Wendelstein 7-X