Lens (EPL)
1.20″
2.00
0.176
0.000
q=0.70, φ=0°
0.00″
0.00″
External Shear
0.000
0°
Perturber (SIS satellite)
0.10″
(0.80, 0.80)″
Drag the orange dot on the image plane to move the perturber. Shift-click anywhere on the image plane to drop it there. Place near a critical curve to see image splitting.
Source — Quasar
1.00
Click/drag on the source plane to move the quasar+host. Lensed images appear on the image plane via ray-tracing.
Source — Host Galaxy (Sérsic)
0.15″
1.0
0.70
30°
0.50
Display
200
500
Cosmology (sets Δt scale)
70.0 km/s/Mpc
0.50
2.00
— d/″²
Δt = (DΔt/c) · Δτ where τ(θ) = ½|θ−β|² − ψ(θ) is the Fermat potential. DΔt(H0, zl, zs) is computed for flat ΛCDM (Ωm=0.3). Slide H0 to see how a measured Δt would constrain it.
Variability
100 d
0.40
800 d
Presets
Image Positions
Move the source to see images
Source Plane
Caustics
Quasar
Host galaxy
β = (0.00, 0.00)
Image Plane
Critical curves
Images A → D (by arrival)
Lensed host (extended)
G — main lens
G1 — perturber
θ = (0.00, 0.00)
◊ Quasar Light Curves & Time Delays
1.0×
Relative Time Delays
Move the source to see images and delays.