Research

Home

Research

In addition to posting material which is not published yet (and in some cases, will never be - I'm sure some of the things I work on are dead ends), these webpages allow access to source code and data files that are typically not included in publications.

Direct Imaging of Exoplanets

Adaptive Optics is used to compensate for atmospheric turbulence on ground-based telescopes. It is a necessary first step to image exoplanets with ground-based telescopes

A Coronagraph is an optical imaging system designed to observe faint sources (planets) very close to much brighter ones (stars)

An Interferometer is a telescope where the entrance pupil is made of several telescopes, and where the distance between these telescopes is somewhat greater than their individual sizes. Interferometers can be larger than individual telescopes, so they are very good at looking very close to stars. With a nulling interferometer, the beams are interfered in a way that blocks the light of the central star, therefore enabling direct imaging of exoplanets.

High precision astrometry of nearby stars with a wide field camera High precision (sub-micro arcsecond) astrometry of nearby bright stars is possible with a space coronagraph with the addition of a wide field diffraction limited camera imaging an annulus of background stars around the central coronagraphic field. The astrometric measurement is performed by simultaneously imaging background stars and diffraction spikes from the much brighter coronagraphic target on the same focal plane array. The diffraction spikes are generated by a series of small dark spots directly on the primary mirror to reduce sensitivity to optical and mechanical distortions.