Cold atoms in space: community workshop summary and proposed road-map

We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies.publishedVersio

THE LINKS BETWEEN TRADE POLICY AND TOTAL FACTOR PRODUCTIVITY IN SOUTH AFRICA'S MANUFACTURING SECTOR

This paper reconfirms the important links that exist between manufacturing productivity, trade orientation, industry specific characteristics and some macroeconomic variables. The dynamic GMM estimator used in the analysis shows that apart from being affected by trade measures, total factor productivity is strongly persistent. In addition, the evolution of the real exchange rate and inflation exert important effects on manufacturing productivity. Most importantly, the dynamic error component specification appears to be more efficient in modelling the effects on manufacturing productivity of policy change than the static approach. Copyright 2005 Economic Society of South Africa.

Z-portal dark matter

We propose to generalize the extensions of the Standard Model where the Z boson serves as a mediator between the Standard Model sector and the dark sector . We show that, like in the Higgs portal case, the combined constraints from the recent direct searches restrict severely the nature of the coupling of the dark matter to the Z boson and set a limit m & 200 GeV (except in a very narrow region around the Z-pole region). Using complementarity between spin dependent, spin independent and FERMI limits, we predict the nature of this coupling, more speci cally the axial/vectorial ratio that respects a thermal dark matter coupled through a Z-portal while not being excluded by the current observations. We also show that the next generation of experiments of the type LZ or XENON1T will test Z-portal scenario for dark matter mass up to 2TeV. The condition of a thermal dark matter naturally predicts the spin-dependent scattering cross section on the neutron to be SD n ' 1040 cm2, which then becomes a clear prediction of the model and a signature testable in the near future experiments.peerReviewe