Inferring the properties of the sources of reionization using the
  morphological spectra of the ionized regions
  High-redshift 21-cm observations will provide crucial insights into the
physical processes of the Epoch of Reionization. Next-generation
interferometers such as the Square Kilometer Array will have enough sensitivity
to directly image the 21-cm fluctuations and trace the evolution of the
ionizing fronts. In this work, we develop an inferential approach to recover
the sources and IGM properties of the process of reionization using the number
and, in particular, the morphological pattern spectra of the ionized regions
extracted from realistic mock observations. To do so, we extend the Markov
Chain Monte Carlo analysis tool 21CMMC by including these 21-cm tomographic
statistics and compare this method to only using the power spectrum. We
demonstrate that the evolution of the number-count and morphology of the
ionized regions as a function of redshift provides independent information to
disentangle multiple reionization scenarios because it probes the average
ionizing budget per baryon. Although less precise, we find that constraints
inferred using 21-cm tomographic statistics are more robust to the presence of
contaminants such as foreground residuals. This work highlights that combining
power spectrum and tomographic analyses more accurately recovers the
astrophysics of reionization.
