performance of phase apodization coronagraphs at the mmt n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Performance of Phase Apodization Coronagraphs at the MMT PowerPoint Presentation
Download Presentation
Performance of Phase Apodization Coronagraphs at the MMT

Loading in 2 Seconds...

play fullscreen
1 / 8
ismet

Performance of Phase Apodization Coronagraphs at the MMT - PowerPoint PPT Presentation

99 Views
Download Presentation
Performance of Phase Apodization Coronagraphs at the MMT
An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Performance of Phase Apodization Coronagraphs at the MMT Michael Gaj Dr. John Codona The University of Arizona Center for Astronomical Adaptive Optics Arizona Space Grant Consortium Statewide Symposium April 18th, 2008

  2. Astronomical Imaging • Two main problems in extrasolar-planet are diffraction patterns and atmospheric speckles. • Although adaptive optics systems do a good job of suppressing atmospheric turbulence, they cannot correct diffraction patterns and speckles. • Some diffraction patterns can be corrected with modern coronagraphs, but they cannot eliminate the speckles.

  3. What is the Phase Apodization Coronagraph? • Unlike other coronagraphs, the PAC is able to eliminate diffraction patterns while maintaining constant telescope position. • Result: • Speckles can be averaged and the background can be smoothed. • Astronomers are now able to observe nearby extrasolar planets thousands of times fainter than their parent star.

  4. Image at MMT with PAC

  5. PAC Efficiency • Although the PAC is a proven method of image correction, the device breaks down and looses its effectiveness at a certain wavelength. • The question then becomes: At what wavelengths can the PAC successfully operate?

  6. Simulated Images at MMT 5 Microns 2.2 Microns 1.65 Microns 1 Micron .8 Microns

  7. Performance of PAC

  8. Results • From the graph, the PAC proved to be most effective at a wavelength of 5 microns. • However, there is very little sensitivity difference for wavelengths of 5, 2.2 and 1.65 microns over an angle of .7 arc seconds. • Wavelengths lower than this value showed no significant improvement in image quality.