NRAO/Socorro Colloquium Series: 17 October 2003

Bohdan Paczynski

Princeton University


Optical Gravitational Lensing Experiment (OGLE)


OGLE is doing massive variability search, mainly toward the Galactic Bulge, and toward the Magellanic Clouds, using a dedicated 1.3 meter telescope located in Chile at the Las Campanas Observatory. Following a major upgrade in mid 2001: a mosaic 8K x 8K CCD camera, the project is now the largest ongoing search for gravitational microlensing, with almost 400 events detected in 2002. It is likely that some events were caused by stellar mass black holes, while others indicate the presence of planets. A search for photometric transits by planets has provided a number of promising candidates. OGLE generated the largest ever catalog of variable stars, with about quarter of a million variables, and hundreds of photometric measurements per object, with all data available over the Internet. A number of quasars was identified through their variability - these will provide inertial reference frame for the Galactic Bulge, LMC and SMC. Proper motions were measured for approximately five million stars, revealing rotation of the Galactic bar.

It is very likely that OGLE will have definite detection of gravitational microlensing by planets in 2003, and the first definite black hole lens detections in 2004 or 2005.






Friday, 17 October 2003
11:00am

Array Operations Center Auditorium

Local Host: Dale Frail


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