  The shaping of astrophysical outflows into bright, dense and collimated jets
due to magnetic pressure is here investigated using laboratory experiments. We
notably look at the impact on jet collimation of a misalignment between the
outflow, as it stems from the source, and the magnetic field. For small
misalignments, a magnetic nozzle forms and redirects the outflow in a
collimated jet. For growing misalignments, this nozzle becomes increasingly
asymmetric, disrupting jet formation. Our results thus suggest outflow/magnetic
field misalignment to be a plausible key process regulating jet collimation in
a variety of objects from our Sun's outflows to extragalatic jets. Furthermore,
they provide a possible interpretation for the observed structuring of
astrophysical jets. Jet modulation could be interpreted as the signature of
changes over time in the outflow/ambient field angle, and the change in the
direction of the jet could be the signature of changes in the direction of the
ambient field.
