Left: H i column density contours, calculated from the 30′′ cube, overlaid on the r-band SDSS image. The contours are given by S_Hi = 2ⁿ × 10¹⁹ cm^-2 (n = 0,1,2,...). The beam size is indicated in the lower-left corner of the figure. Middle: intensity-weighted mean velocity field calculated from the 30′′ cube, the iso-velocity contours correspond to V_sys ± n × 50 km s^-1, where n = 1,2,3,... and V_sys = 1048 km s^-1. Right: position-velocity diagram along the major axis of the 15′′ H i cube. The white scale bar indicates 10 kpc.