Krzysztof Rybicki (Weitzmann Institute of Science): "Microlensing Observations with Spitzer, Gaia and Roman Satellites"


The study of isolated dark remnants, such as stellar mass black holes and neutron stars in the Milky Way is of great importance for our understanding of the last phases of stellar evolution and the general structure of the Galaxy. Microlensing is a powerful technique for identifying these objects, but the standard events often lack the necessary information to accurately determine all the lens properties, particularly the mass. This hinders our ability to distinguish between events caused by stellar remnants, even though there should be many such events among the ~30,000 microlensing events detected to date. In this talk, I will discuss how the Spitzer and Gaia satellites can be used to tackle the problem of measuring lens mass in microlensing events. Spitzer's archival data allows for the detection of microlensing parallax, which is crucial for measuring lens masses. Gaia astrometry can be used to identify and characterize the lensing objects thanks to the measurement of the centroid shift and thus the Einstein radius. Last but not least, I will discuss the future Nancy Grace Roman Telescope, and the huge impact that it is expected to have on the field of microlensing (and astrophysics in general).

Date: 12:15 PM, May 10th, 2023
Location: MR-102 and online, please visit to sign up to get talk announcements with Zoom URLs.
Category: Science Talk