Expansion-maximization-compression algorithm with spherical harmonics for single particle imaging with X-ray lasers
Abstract
In 3D single particle imaging with X-ray free-electron lasers, particle orientation is not recorded during measurement but is instead recovered as a necessary step in the reconstruction of a 3D image from the diffraction data. Here we use harmonic analysis on the sphere to cleanly separate the angu- lar and radial degrees of freedom of this problem, providing new opportunities to efficiently use data and computational resources. We develop the Expansion-Maximization-Compression algorithm into a shell-by-shell approach and implement an angular bandwidth limit that can be gradually raised during the reconstruction. We study the minimum number of patterns and minimum rotation sampling required for a desired angular and radial resolution. These extensions provide new av- enues to improve computational efficiency and speed of convergence, which are critically important considering the very large datasets expected from experiment.
Cite
@article{arxiv.1602.01301,
title = {Expansion-maximization-compression algorithm with spherical harmonics for single particle imaging with X-ray lasers},
author = {Julien Flamant and Nicolas Le Bihan and Andrew V. Martin and Jonathan H. Manton},
journal= {arXiv preprint arXiv:1602.01301},
year = {2016}
}