The validation of made-to-measure method for reconstruction of phase
  space distribution functions
  We investigate how accurately phase space distribution functions (DFs) in
galactic models can be reconstructed by a made-to-measure (M2M) method, which
constructs $N$-particle models of stellar systems from photometric and various
kinematic data. The advantage of the M2M method is that this method can be
applied to various galactic models without assumption of the spatial symmetries
of gravitational potentials adopted in galactic models, and furthermore,
numerical calculations of the orbits of the stars cannot be severely
constrained by the capacities of computer memories. The M2M method has been
applied to various galactic models. However, the degree of accuracy for the
recovery of DFs derived by the M2M method in galactic models has never been
investigated carefully. Therefore, we show the degree of accuracy for the
recovery of the DFs for the anisotropic Plummer model and the axisymmetric
St\"{a}ckel model, which have analytic solutions of the DFs. Furthermore, this
study provides the dependence of the degree of accuracy for the recovery of the
DFs on various parameters and a procedure adopted in this paper. As a result,
we find that the degree of accuracy for the recovery of the DFs derived by the
M2M method for the spherical target model is a few percent, and more than ten
percent for the axisymmetric target model.
