Automation and robotics for COLUMBUS: An implementation concept for the free flying laboratory (MTFF)

With nearly forty percent of the funding, Germany is the main contributor to the European COLUMBUS Programme, followed by Italy, France and further ESA member states. The COLUMBUS elements are the Attached Laboratory (APM) to be permanently attached to the Space Station FREEDOM, the polar platform (PPF) and the Man Tended Free Flyer (MTFF). The latter element is regarded to be of special interest for the German micro-g community. Until now the implementation of A&R Technologies has not been included as part of the system concept for the COLUMBUS laboratory modules. Yet especially for the Free Flyer, a high degree of A&R will be indispensible. An A&R system concept and implementation options for A&R are given to make the COLUMBUS labs 'intelligent' laboratories in orbit

Frontal Eye Field Neurons Assess Visual Stability Across Saccades

The image on the retina may move because the eyes move, or because something in the visual scene moves. The brain is not fooled by this ambiguity. Even as we make saccades, we are able to detect whether visual objects remain stable or move. Here we test whether this ability to assess visual stability across saccades is present at the single-neuron level in the frontal eye field (FEF), an area that receives both visual input and information about imminent saccades. Our hypothesis was that neurons in the FEF report whether a visual stimulus remains stable or moves as a saccade is made. Monkeys made saccades in the presence of a visual stimulus outside of the receptive field. In some trials, the stimulus remained stable, but in other trials, it moved during the saccade. In every trial, the stimulus occupied the center of the receptive field after the saccade, thus evoking a reafferent visual response. We found that many FEF neurons signaled, in the strength and timing of their reafferent response, whether the stimulus had remained stable or moved. Reafferent responses were tuned for the amount of stimulus translation, and, in accordance with human psychophysics, tuning was better (more prevalent, stronger, and quicker) for stimuli that moved perpendicular, rather than parallel, to the saccade. Tuning was sometimes present as well for nonspatial transaccadic changes (in color, size, or both). Our results indicate that FEF neurons evaluate visual stability during saccades and may be general purpose detectors of transaccadic visual change

Some measurements of the dynamic and static stability of two blunt-nosed, low-fineness- ratio bodies of revolution in free flight at mequal4

Dynamic and static stability of two blunt nosed low fineness ratio bodies of revolution in free flight - ballistic

Quarkonia Measurements with the Central Detectors of ALICE

A Large Ion Collider Experiment - ALICE will become operational with the startup of the Large Hadron Collider - LHC at the end of 2007. One focus of the physics program is the measurement of quarkonia in proton-proton and lead-lead collisions. Quarkonia states will be measured in two kinematic regions and channels: di-muonic decays will be measured in the forward region by the muon arm, the central part of the detector will measure di-electronic decays. The presented studies show the expected performance of the di-electron measurement in proton-proton and central lead-lead collisions.Comment: 6 pages, 7 figures, Proceedings of the QM 2006 poster sessio

No nearby counterparts to the moving objects in the Hubble Deep Field

Ibata et al (1999) have recently discovered faint, moving objects in the Hubble Deep Field. The quantity, magnitudes and proper motions of these objects are consistent with old white dwarfs making up the Galactic dark halo. We review a number of ground-based proper motion surveys in which nearby dark halo white dwarfs might be present, if they have the colours and absolute magnitudes proposed. No such objects have been found, whereas we argue here that several times more would be expected than in the Hubble Deep Field. We conclude it is unlikely that hydrogen atmosphere white dwarfs make up a significant fraction of the halo dark matter. No limits can be placed yet on helium atmosphere dwarfs from optical searches.Comment: 7 pages, 4 figures, MNRAS LaTeX forma