Evidence for the gravity-driven and magnetically regularized gas flows feeding the massive protostellar cluster in Cepheus A

The hierarchical interplay among gravity, magnetic fields, and turbulence in forming massive protostellar clusters remains elusive. We present high-resolution (~14 arc seconds ≃ 0.05 parsecs), 850-micrometer dust polarization and C 18 O line observations of Cepheus A using JCMT SCUBA-2/POL-2 and HARP. Our analysis reveals aligned gravitational (G), magnetic (B), and velocity fields (K), with an energy hierarchy of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow