An X-ray Proper Motion Study of the LMC SNR 0509-67.5

We present a third epoch of Chandra observations of the Type Ia Large Magellanic Cloud Supernova remnant (SNR) 0509-67.5. With these new observations from 2020, the baseline for proper motion measurements of the expansion has grown to 20 years (from the earliest Chandra observations in 2000). We report here the results of these new expansion measurements. The lack of nearby bright point sources renders absolute image alignment difficult. However, we are able to measure the average expansion of the diameter of the remnant along several projection directions. We find that the remnant is expanding with an average velocity of 6120 (4900 -- 7360) km s$^{-1}$. This high shock velocity is consistent with previous works, and also consistent with the inference that 0509-67.5 is expanding into a very low density surrounding medium. At the distance of the LMC, this velocity corresponds to an undecelerated age of 600 yrs, with the real age somewhat smaller.