Velocity gradient intensities |∇v_LSR| calculated from the Gaussian fit to HC₃N (10 − 9) emission, with the gradient directions visualized as an overplotted texture using line integral convolution (LIC. Cabral & Leedom 1993). The black star indicates the position of B5-IRS1. The black ellipse in the bottom left corner represents the beam size. The red circle at the top right corner represents the area used to calculate the gradients. White dashed contours outline the NH₃ filaments (P15; S21). White solid contours outline the edges of the condensations (P15). The scalebar at the bottom right corner represents a physical distance of 5000 au.