Velocity vector (3D) measurement for spherical objects using an electro-optical device

The present paper describes a procedure to measure the velocity vector (3D) of a spherical object using an electro-optical device configured as a single large detection area optical barrier. The proposed procedure allows a measurement accuracy up to 0.1% in some cases and presents several advantages in relation to other measurement procedures like image processing, doppler-radar and some other electro-optical devices. The procedure is independent of the relative position of the measurement device in relation to the object trajectory. The fact of using a single optical barrier reduces the space required in the movement direction and increase the cases where the device can be used. A prototype has been built and tested.Lluna Gil, E.; Santiago-Praderas, V.; Defez Garcia, B.; Dunai, L.; Peris Fajarnes, G. (2011). Velocity vector (3D) measurement for spherical objects using an electro-optical device. Measurement. 44(9):1723-1729. doi:10.1016/j.measurement.2011.07.006S1723172944

OGLE-2005-BLG-018: Characterization of Full Physical and Orbital Parameters of a Gravitational Binary Lens

We present the analysis result of a gravitational binary-lensing event OGLE-2005-BLG-018. The light curve of the event is characterized by 2 adjacent strong features and a single weak feature separated from the strong features. The light curve exhibits noticeable deviations from the best-fit model based on standard binary parameters. To explain the deviation, we test models including various higher-order effects of the motions of the observer, source, and lens. From this, we find that it is necessary to account for the orbital motion of the lens in describing the light curve. From modeling of the light curve considering the parallax effect and Keplerian orbital motion, we are able to measure not only the physical parameters but also a complete orbital solution of the lens system. It is found that the event was produced by a binary lens located in the Galactic bulge with a distance $6.7\pm 0.3$ kpc from the Earth. The individual lens components with masses $0.9\pm 0.3\ M_\odot$ and $0.5\pm 0.1\ M_\odot$ are separated with a semi-major axis of $a=2.5 \pm 1.0$ AU and orbiting each other with a period $P=3.1 \pm 1.3$ yr. The event demonstrates that it is possible to extract detailed information about binary lens systems from well-resolved lensing light curves.Comment: 19 pages, 6 figure

Dependable Software Technology Exchange

On March 18 and 19, 1993, the Dependable Real-Time Software Project hosted a Dependable Software Technology Exchange. The exchange, sponsored by the Air Force Space and Missile Systems Center and the Office of Naval Research, brought together researchers and system developers, providing an opportunity for the researchers to learn the needs of the developers and for the developers to learn about techniques being investigated by the researchers. This report summarizes what transpired at the meeting