(University of Washington)
Surveys of gravitational shear due to large-scale structure are becoming
an important tool for precise measurements of cosmological parameters,
including the possible evolution of dark energy.
Many of the new statistical tools being developed in this field rely
on obtaining unbiased lensing mass maps over large fields: fields which
will, in general, have complicated geometries and masking
due to inhomogeneous sky coverage, foreground sources, etc. We have
developed an interpolation procedure for gappy shear fields based
on Karhunen-Loeve (KL) decomposition. Along with interpolation, the
KL analysis results in a suppression of noise on scales relevant to
cosmological studies using shear peaks.
In this talk, I will review recent studies of the cosmological information
encoded in high-convergence regions of shear fields, and show how our
new KL framework addresses some potential problems with this approach..