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Number of Results: 1 Search : Einstein radius

Einstein radius šo'â'-e Einstein Fr.: rayon d'Einstein In gravitational lens phenomenon, the critical distance from the
→ d)_{L}.d_{S}^{0.5},
where G is the → gravitational constant,
M is the mass of the lens, c is the
→ speed of light, d is the
angular diameter distance to the lens,
_{L}d is the angular diameter distance to the source, and
_{S}d is the angular diameter distance between the
lens and the source. The equation can be simplified to:
θ_{LS}_{E} = (0''.9) (M/10^{11}Msun)^{0.5}
(D/Gpc)^{-0.5}.
Hence, for a dense cluster with mass
M ~ 10 × 10^{15} Msun at a distance of 1
Gigaparsec (1 Gpc) this radius is about 100 arcsec.
For a gravitational → microlensing event
(with masses of
order 1 Msun) at galactic distances (say D ~ 3 kpc), the
typical Einstein radius would be of order
milli-arcseconds. |