Shell galaxies as laboratories for testing MOND
  Tests of MOND in ellipticals are relatively rare because these galaxies often
lack kinematic tracers in the regions where the MOND effects are significant.
Stellar shells observed in many elliptical galaxies offer a promising way to
constrain their gravitational field. Shells appear as glowing arcs around their
host galaxy. They are observed up to ~100 kpc. The stars in axially symmetric
shell systems move in nearly radial orbits. The radial distributions of shell
locations and the spectra of stars in shells can be used to constrain the
gravitational potential of their host galaxy. The symmetrical shell systems,
being especially suitable for these studies, occur in approximately 3% of all
early-type galaxies. Hence the shells substantially increase the number of
ellipticals in which MOND can be tested up to large radii. In this paper, we
review our work on shell galaxies in MOND. We summarize the paper B\'{i}lek et
al. (2013), where we demonstrated the consistency of shell radii in an
elliptical NGC 3923 with MOND, and the work B\'{i}lek et al. (2014), in which
we predicted a giant (~200 kpc), as yet undiscovered shell of NGC 3923. We
explain the shell identification method, which was used in these two papers. We
further describe the expected shape of line profiles in shell spectra in MOND
which is very special due to the direct relation of the gravitational field and
baryonic matter distribution (B\'{i}lek et al., 2014, in preparation).
