Extended Data Fig. 4: Proper motions of the halo sample.
From: All-sky dynamical response of the Galactic halo to the Large Magellanic Cloud
a, Proper motions of the K giants at 60 < Rgal < 100 kpc with 12 < W1 < 15 and the LMC and the SMC removed via on-sky selection. b, Solar reflex-corrected proper motions. Notice the much tighter distribution of stars near (0, 0). In this panel, the Sagittarius dSph is visible at (−2.5, −0.7) and LMC and SMC stars not removed by the on-sky selection are visible as a narrow vertical strip at μα ≳ 0.5 mas yr−1. The northern Sagittarius arm is the large overdensity at (−0.7, 0.0) and a southern arm of Sagittarius is the diagonal cluster of points at μδ < −0.5 mas yr−1. c, Reflex-corrected proper motions focusing on the region of the sky containing the northern Sagittarius arm at l ≈ 0°. The red box indicates our selection for removing this feature. d, Stars not in the selection shown in c. Our selection for low proper motion stars is indicated by a blue circle in c and d.
