Binary-lens model light curve plotter

d q

u0 α


τmin τmax

δ1 δ2 Δ

Event t0 tE

m0 g use fit

With θ E denoting the angular Einstein radius that refers to the total mass of the lens system, the angular separation of its components is given by dθ E, while q is the secondory-to-primary mass ratio. The lens components are oriented along the horizontal axis, with the primary on the right. The trajectory of the source on the sky relative to the centre of mass of the lens system, which marks the coordinate origin, is θ(τ) = [u0 (-sin α; cos α) + τ  (cos α; sin &alpha)] θE, and its angular radius is ρθE. The sky region displayed is centred around (δ1; δ2 ) θ E, and its width and height are 2Δ θ E.
Please acknowledge the use of this tool and refer to M. Dominik 2007, MNRAS 377, 1679.
© 2007 Martin Dominik