im3shape: a maximum likelihood galaxy shear measurement code for cosmic gravitational lensing

  title={im3shape: a maximum likelihood galaxy shear measurement code for cosmic gravitational lensing},
  author={J. Zuntz and T. Kacprzak and L. Voigt and M. Hirsch and B. Rowe and S. Bridle},
  journal={Monthly Notices of the Royal Astronomical Society},
  • J. Zuntz, T. Kacprzak, +3 authors S. Bridle
  • Published 2013
  • Physics
  • Monthly Notices of the Royal Astronomical Society
  • We present and describe IM3SHAPE, a new publicly available galaxy shape measurement code for weak gravitational lensing shear. IM3SHAPE performs a maximum likelihood fit of a bulgeplus-disc galaxy model to noisy images, incorporating an applied point spread function. We detail challenges faced and choices made in its design and implementation, and then discuss various limitations that affect this and other maximum like lihood methods. We assess the bias arising from fitting an incorrect galaxy… CONTINUE READING
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