title: Dragonfly: an implementation of the expand-maximize-compress algorithm for single-particle imaging.
abstract: Single-particle imaging (SPI) with X-ray free-electron lasers has the potential to change fundamentally how biomacromolecules are imaged. The structure would be derived from millions of diffraction patterns, each from a different copy of the macromolecule before it is torn apart by radiation damage. The challenges posed by the resultant data stream are staggering: millions of incomplete, noisy and un-oriented patterns have to be computationally assembled into a three-dimensional intensity map and then phase reconstructed. In this paper, theDragonflysoftware package is described, based on a parallel implementation of the expand-maximize-compress reconstruction algorithm that is well suited for this task. Auxiliary modules to simulate SPI data streams are also included to assess the feasibility of proposed SPI experiments at the Linac Coherent Light Source, Stanford, California, USA.
authors: Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors: Kartik
authors: K
authors: Ayyer
authors: Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA.
authors: Ti-Yen
authors: TY
authors: Lan
authors: Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA.
authors: Veit
authors: V
authors: Elser
authors: Centre for Bio-imaging Sciences, National University of Singapore, 14 Science Drive 4, 117557, Singapore; Department of Physics, National University of Singapore, 2 Science Drive 3, 117551, Singapore; Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117557, Singapore.
authors: N Duane
authors: ND
authors: Loh
keywords: X-ray free-electron lasers; XFELs; expand–maximize–compress reconstruction algorithm; single-particle imaging