Structured velocity field in the inner envelope of B335: ALMA observations of rare CO isotopologues

Context. Studies of Class 0 objects allow to characterize the dynamical processes taking place at onset star formation process and determine physical mechanisms responsible for outcome collapse. Observations dense gas tracers characterization key kinematics that are directly involved in process, such as infall, outflow, rotation. Aims. This work is aimed investigating molecular line velocity profiles protostellar object B335 attempts constraints on infall motions happening circumstellar object. Methods. We present observations C 17 O (1–0), 18 12 CO (2–1) transitions along with an analysis spectral envelope radii between 100 860 au. Results. emission presents a double-peaked profile distributed complex field. Both peaks offset 0.2–1 km s −1 from systemic source probed area. The optical depth has been estimated found be less than 1, suggesting two trace distinct components inner envelope. Conclusions. After discarding possible could produce pattern, rotation we conclude producing Because inside-out symmetric collapse cannot explain those observed profiles, it suggested these produced by non-isotropic accretion into central outflow cavity walls.