  Relativistic beams of heavy ions interacting with various nuclear targets
allow to study a broad range of problems starting from nuclear equation of
state to the traditional nuclear structure. Some questions which were
impossible to answer heretofore -- can be addressed nowadays by using inverse
kinematics. These includes the structure of short-lived nuclei and the
precision study of exclusive channels with production of residual nuclei in
certain quantum states. Theoretical understanding such processes is so far
based on factorization models which combine the single-step amplitude of the
reaction on a bound nucleon or nuclear cluster with a certain wave function of
its relative motion with respect to the residual nucleus. The nuclear structure
information is encoded in the spectroscopic amplitude, calculable within
nuclear many-body theories. In this work, we use for this purpose the
translationally-invariant shell model with configuration mixing and demonstrate
that it successfully reproduces the single-differential and integrated cross
sections of the quasielastic proton knockout,
$^{12}\mbox{C}(p,2p)^{11}\mbox{B}$, with outgoing $^{11}$B in the ground state
and low-lying excited states measured at GSI at 400 MeV/nucleon.
