J. R. Crepp, J. Ge (University of Florida), M. J. Kuchner (Princeton), A. V. Heuvel, X. Wan (University of Florida), S. Miller (Penn State)
An ideal coronagraph equipped with a notch filter image mask is capable of achieving infinite dynamic range and high throughput in a broadband survey for extrasolar planets. In addition, a coronagraph with an eighth-order notch filter image mask is robust to pointing errors and is better suited for generating regions of high contrast around stars of appreciable angular size. In collaboration with the nanofabrication facilities at Penn State and the University of Florida, we have built and tested a second generation of binary notch filter image masks: 2 eighth-order masks and 3 fourth-order masks. We present experimental results of their performance with monochromatic and broadband visible light and show that notch filter image masks provide deep suppression of light very near the optical axis in practice. This comprehensive study illustrates the interplay between inner-working angle, search area, throughput, and pointing requirements between various fourth-order and eighth-order designs.
The author(s) of this abstract have provided an email address for comments about the abstract: jcrepp@astro.ufl.edu
Bulletin of the American Astronomical Society, 36 5
© 2004. The American Astronomical Society.