  This paper presents recent experimental results on the yield of prompt
fission $\gamma$ rays from the spontaneous fission of $^{252}$Cf. We use an
ionization chamber to tag fission events and measure the masses and kinetic
energies of the fission fragments and trans-stilbene organic scintillators to
measure the neutrons and $\gamma$ rays emitted by the fission fragments. The
combination of the ionization chamber and trans-stilbene scintillators allows
us to determine the properties of neutrons and $\gamma$ rays in coincidence
with the fragments. The yield of $\gamma$ rays is known to be influenced by the
angular momenta (AM) of the fission fragments. We present new experimental
evidence that indicates that the total $\gamma$-ray multiplicity, i.e., the sum
of both fragments' emission, saturates at sufficiently high internal fragment
excitation energies. We also observe distinct behaviors for the yield of
$\gamma$ rays from the light and heavy fragment, which for certain mass and
total kinetic energy (TKE) regions are weakly or anti-correlated, indicating
the presence of complex AM generation modes. We also observed a mass- and
TKE-dependent anisotropy of the $\gamma$ rays, which challenges and expands on
the conventional notion that the fragments' AM are always aligned
perpendicularly to the fission axis. Moreover, the dependence of the anisotropy
on mass and TKE indicates a dependence of these properties on the specific
fission channels, thus providing an insight into the deformations and dynamics
in fission and their connection with experimentally observable quantities.
