  We present a new method to reconstruct the three-dimensional electron density
of coronal mass ejections (CMEs) based on a genetic algorithm, namely the
genetic reconstruction method (GRM). GRM is first applied to model CMEs with
different orientations and shapes. A set of analytic model CMEs from Gibson and
Low is employed to produce synthetic CME images for GRM reconstruction. Model
CMEs with longitudes of 0, 45, 90, 135, 180 degrees and latitudes of 0, 15, 30,
45 degrees are used to test the performance of GRM. The model CMEs are obscured
with a simulated occulter of a coronagraph to determine the influence of CME
brightness incompleteness. We add random noise to some synthetic CME images to
test the performance of GRM. The CME reconstructions are carried out using
synthetic data from Solar Terrestrial Relations Observatory (STEREO) A and B
with a separation angle of 90 degrees and from STEREO A and the Solar and
Heliospheric Observatory (SOHO) with a separation angle of 73 degrees. The
Pearson correlation coefficient and the mean relative absolute deviation are
calculated to analyze the similarities in brightness and electron density
between the model and reconstructed CMEs. Comparisons based on the similarity
analysis under various conditions stated above give us valuable insights into
the advantages and limitations of GRM reconstruction. The method is then
applied to real coronagraph data from STEREO A and B, and SOHO on 2013
September 30.
