Detecting Extra-Solar Planets via Microlensing at High Magnification

Nicholas  Rattenbury
Department of Physics
University of Auckland

Extra-solar planets can be efficiently detected in gravitational
microlensing events of high magnification. High accuracy photometry is
required over a short, well-defined time interval only, of order 10-30
hours. Most planets orbiting the lens star are evidenced by perturbations
of the microlensing lightcurve in this time. Consequently, telescope resources
need be concentrated during this period only.

The Japanese/New Zealand collaboration MOA (Microlensing Observations in
Astrophysics) continues to detect and alert microlensing events of high
magnifiaction to the community at
http://www.phys.canterbury.ac.nz/~physib/alert/alert.html 
promoting follow-up observations.

Here we discuss some aspects of planet detection in these events
including:-

* zones of detectability of terrestrial, ice-giant and gas-giant
planets
* detectability of multi-planet systems
* detectability of solar system analogues
* detectability of habitable planets
* effects of the size of the source star, and the presence of spots
on the source star
* effect of orbital rotation during an event
* cluster computing for simulations and modelling
* applications to proposed space-based missions