Relationship between [O II] velocity fields and whole-galaxy dynamics

Determine whether the [O II] velocity field in tadpole galaxies represents the kinematics of the entire galaxy or primarily traces the actively star-forming regions.

Background

The kinematic analysis uses [O II] emission, which traces ionized gas associated with active star-forming regions rather than directly measuring the motion of the underlying stellar disk or the cold molecular and atomic gas reservoirs.

Because the bright star-forming head may dominate the [O II] signal, the measured velocity field could provide a biased view of the global dynamical state. The authors therefore identify the correspondence between [O II] kinematics and whole-galaxy kinematics as unresolved.

References

One must first answer whether the [O\,{\sc ii}] velocity field represent the kinematics of the entire galaxy or primarily of the star-forming regions \citep{Baker_etal2025}.

— The kinematics of tadpole galaxies at intermediate redshift $z \sim 0.4 - 1.5$  (2609.10532 - Kataria et al., 9 Sep 2026) in Section 9, Discussion and conclusions