  We report the electronic structure reconstruction of
Ca$_{1-x}$Pr$_x$Fe$_2$As$_2$ ($x$ = 0.1 and 0.15) in the low temperature
collapsed tetragonal (CT) phase observed by angle-resolved photoemission
spectroscopy. Different from Ca(Fe$_{1-x}$Rh$_x$)$_2$As$_2$ and the annealed
CaFe$_2$As$_2$ where all hole Fermi surfaces are absent in their CT phases, the
cylindrical hole Fermi surface can still be observed in the CT phase of
Ca$_{1-x}$Pr$_x$Fe$_2$As$_2$. Furthermore, we found at least three well
separated electron-like bands around the zone corner in the CT phase of
Ca$_{1-x}$Pr$_x$Fe$_2$As$_2$, which are more dispersive than the electron-like
bands in the high temperature tetragonal phase. Based on these observations, we
propose that the weakening of correlations (as indicated by the reduced
effective mass), rather than the lack of Fermi surface nesting, might be
responsible for the absence of magnetic ordering and superconductivity in the
CT phase.

Superconductivity