  Quantum control of molecular collision dynamics is an exciting emerging area
of cold collisions. Co-expansion of collision partners in a supersonic
molecular beam combined with precise control of their quantum states and
alignment/orientation using Stark-induced Adiabatic Raman Passage allows
exquisite stereodynamic control of the collision outcome. This approach has
recently been demonstrated for rotational quenching of HD in collisions with
H2, D2, and He and D2 by He. Here we illustrate this approach for
HD(v=0,j=2)+CO(v=0,j=0) -> HD(v'=0,j')+CO(v'=0,j') collisions through
full-dimensional quantum scattering calculations at collision energies near 1
K. It is shown that the collision dynamics at energies between 0.01--1K are
controlled by an interplay of L=1 and L=2 partial wave resonances depending on
the final rotational levels of the two molecules. Polarized cross-sections
resolved into magnetic sub-levels of the initial and final rotational quantum
numbers of the two molecules also reveal a significant stereodynamic effect in
the cold energy regime. Overall, the stereodynamic effect is controlled by both
geometric and dynamical factors, with parity conservation playing an important
role in modulating these contributions depending on the particular final state.
