Fast Computation of the Narcissus Reflection Coefficient for the Herschel Far-Infrared/Submillimeter-Wave Cassegrain Telescope

Abstract

Placement of a scatter cone at the center of the secondary of a Cassegrain telescope greatly reduces Narcissus reflection. To calculate the remaining Narcissus reflection, a time-consuming physical optics code such as GRASP8 is often used to model the effects of reflection and diffraction. Fortunately, the Cassegrain geometry is sufficiently simple that a combination of theoretical analysis and Fourier propagation can yield rapid, accurate results at submillimeter wavelengths. We compare these results with those from GRASP8 for the heterodyne instrument for the far-infrared on the Herschel Space Observatory and confirm the effectiveness of the chosen scatter cone design.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 2005
Accession Number
ADA461544

Entities

People

  • Arturo M. Polegre
  • Douwe A. Beintema
  • Jacqueline Fischer
  • Robert L. Lucke

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Cassegrain Telescopes
  • Coefficients
  • Computations
  • Detection
  • Diffraction
  • Electromagnetic Radiation
  • Focal Planes
  • Frequency
  • Geometry
  • Jet Propulsion
  • Military Research
  • Optical Lattices
  • Radiation
  • Reflection
  • Standing Waves
  • Telescopes
  • Terahertz Radiation

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics
  • Optical Physics and Photonics.
  • Wave Propagation and Nonlinear Chaotic Dynamics.

Technology Areas

  • Space