Top: running median of the longitude PM, μ_l, for RC stars in the range K₀ = 12.5 − 13.5, as a function of longitude, for the NSD strip. The green and brown rectangles mark the approximate locations where the longitude velocity goes to zero, as possible edges of the NSD. The purple rectangles mark the approximate edges of the CMZ. Gray dashed lines are the positions at which Schönrich et al. (2015) found the RV positive and negative peak, respectively, while black dotted lines are the peaks found by Schultheis et al. (2021). The cross marks the position of the GC, while a thin black line shows V_Y = 0. Bottom: rotation curves corresponding to the green and brown rectangles of the top panel. See text for details.