2,665 research outputs found
Atom Interferometry in Space: Thermal Management and Magnetic Shielding
Atom interferometry is an exciting tool to probe fundamental physics. It is
considered especially apt to test the universality of free fall by using two
different sorts of atoms. The increasing sensitivity required for this kind of
experiment sets severe requirements on its environments, instrument control,
and systematic effects. This can partially be mitigated by going to space as
was proposed, for example, in the Spacetime Explorer and Quantum Equivalence
Principle Space Test (STE-QUEST) mission. However, the requirements on the
instrument are still very challenging. For example, the specifications of the
STE-QUEST mission imply that the Feshbach coils of the atom interferometer are
allowed to change their radius only by about 260 nm or 2.6E-4% due to thermal
expansion although they consume an average power of 22 W. Also Earth's magnetic
field has to be suppressed by a factor of 10E5. We show in this article that
with the right design such thermal and magnetic requirements can indeed be met
and that these are not an impediment for the exciting physics possible with
atom interferometers in space.Comment: v2: minor changes to agree with published version; 8 pages, 6 figure
Measuring On-Demand Audiovisual Services - The European Experience
editorial reviewedCette contribution analyse la problématique de la
collecte de données et de l’analyse du marché des
services audiovisuels Ă la demande en Europe, plus
particulièrement dans l’Union européenne. Sont analysés
le cadre réglementaire, les questions de déinition, le
recensement des services, l’analyse des données relatives
à la taille des marchés et à la consommation, la mesure
des activités des services audiovisuels à la demande dans
la promotion des oeuvres européennes (contribution au
inancement, présence des oeuvres européennes dans les
catalogues, mise en évidence des oeuvres européennes).
La contribution se base largement sur les travaux de
l’Observatoire européen de l’audiovisuel (Conseil de
l’Europe – Strasbourg), mais tient compte également
d’autres sources, publiques, professionnelles et privées.his contribution analyses the problems involved in data
collection and market analysis of on-demand audiovisual
services in Europe, and speciically within the European
Union. It addresses the regulatory framework, deinition
issues, the listing of services, the analysis of data related
to market size and consumption, the measurement of
on-demand audiovisual business in the promotion of
European works (financial contribution, presence of
European works in catalogs, showcasing of European
works). he contribution is largely based on work carried
out by the European Audiovisual Observatory (Council
of Europe – Strasbourg), but also takes into account other
public, professional and private sources
Activities of the European Audiovisual Observatory in the Field of Statistical Information
editorial reviewedEstablished in December 1992, the European
Audiovisual Observatory is a unique pan-European
public service organisation dedicated
to gathering and distributing information on
the European audiovisual industry (film, television,
home video, new media). Currently
35 European States as well as the European
Community are members of the Observatory.
The Observatory functions within the framework
of an enlarged partial agreement of the
Council of Europe and carries out its mission
with a network of partners, correspondents
and professional organisations.
Collection and publication of statistics is one
of the important activities of the Observatory.
General strategy, methodological issues,
databases and recent results will be presented.Créé en décembre 1992, l’Observatoire européen
de l’audiovisuel est un organisme de
service public consacré à la collecte et à la
diffusion de l’information sur l’industrie audiovisuelle
(cinéma, télévision, vidéo, nouveaux
médias) en Europe. Trente-cinq États européens
en sont membres ainsi que la Communauté
européenne. L’Observatoire fonctionne
dans le cadre d’un Accord partiel élargi du
Conseil de l’Europe et remplit sa mission avec
un réseau de partenaires, de correspondants
et d’organismes professionnels.
La collecte et la diffusion d’information statistique
constitue une de ses activités principales.
On en présentera la stratégie générale, les
principaux problèmes méthodologiques, la
mise au point de diverses bases de données
ainsi que quelques résultats récents
La production indépendante aux Etats-Unis
editorial reviewedNote d electure Cicchetti, C. et al., The Economic
Consequence of Independent Film
Making. A Report of Arthur Andersen
Economic Consulting and Arthur Andersen
LLP for American Film Market ing
Association, AFMA, Los Angeles, January
1995
« Le Grand Prix Eurovision de la Chanson : chansons de divertissement ou chansons de diversion ? »,
editorial reviewe
Entwicklung einer hocheffektiven Magnetfeldabschirmung fĂĽr die Forschungsraketenmission MAIUS-1
The goal of the MAIUS-1 sounding rocket mission is the realization of the first Bose-Einstein-Condensate and following atom interferometry measurements in space. The hardware of this experiment is specifically designed to match the requirements of a sounding rocket mission. Since the different techniques to create a Bose-Einstein-Condensate like magneto-optical traps and the following atom interferometry methods are very sensitive to external magnetic fields, a effective magnetic shielding is necessary. In this work the design and also the magnetic properties and flight-readiness test procedures are described in great detail. The three-layer magnetic shielding provides a high shielding effectiveness factor of S 1000 for an undisturbed operation of the experiment. With this magnetic shielding it was possible to create the first Bose-Einstein-Condensate in space during the flight of the MAIUS-1 sounding rocket
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