[Russian version]


M a i n    p a g e

Future  seminars

P a s t  seminars

Seminar council


" Exoplanet searches with microlensing "

A.F. Zakharov (Institute of Theoretical and Experimental Physics)



Different regimes of gravitational lensing depend on masses of lens and correspond roughly an angular distance between images. If a gravitational lens has a typical stellar mass, this regime is named as microlensing because a typical angular distance between images is about microarcseconds in the case if sources and lenses are located at cosmological distances. An angular distance depends as a squared root of a lens mass, therefore, if a lens has a typical Earth-like planet mass $10^{-6} M_{\odot}$, the regime is called such as nanolensing. Thus, generally speaking, one can call a regime with a planet mass lens such as nanolensing (independently on locations of lenses and sources). So, one can name searches for planets with gravitational lens method as gravitational nanolensing. There are different methods to find exoplanets as such radial spectral shifts, astrometrical measurements, transits, pulsar timing etc. Gravitational microlensing (including pixel-lensing) is among the most promising techniques if we are interested to find Earth-like  planets at distances about a few astronomical units from the host star.