Measurement of Galactic Logarithmic Spiral Arm Pitch Angle Using
  Two-Dimensional Fast Fourier Transform Decomposition
  A logarithmic spiral is a prominent feature appearing in a majority of
observed galaxies. This feature has long been associated with the traditional
Hubble classification scheme, but historical quotes of pitch angle of spiral
galaxies have been almost exclusively qualitative. We have developed a
methodology, utilizing two-dimensional fast Fourier transformations of images
of spiral galaxies, in order to isolate and measure the pitch angles of their
spiral arms. Our technique provides a quantitative way to measure this
morphological feature. This will allow comparison of spiral galaxy pitch angle
to other galactic parameters and test spiral arm genesis theories. In this
work, we detail our image processing and analysis of spiral galaxy images and
discuss the robustness of our analysis techniques.
