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Abstract We present results from the Chandra X-ray Observatory Large Project (878 ks in 28 observations) of the Large Magellanic Cloud supernova remnant N132D. We measure the expansion of the forward shock in the bright southern rim to be $0\stackrel{″}{.}10\pm 0\stackrel{″}{.}02$over the ∼14.5 yr baseline, which corresponds to a velocity of 1620 ± 400 km s⁻¹after accounting for several instrumental effects. We measure an expansion of $0\stackrel{″}{.}23\pm 0\stackrel{″}{.}02$and a shock velocity of 3840 ± 260 km s⁻¹for two features in an apparent blowout region in the northeast. The emission-measure-weighted average temperature inferred from X-ray spectral fits to regions in the southern rim is 0.95 ± 0.17 keV, consistent with the electron temperature implied by the shock velocity after accounting for Coulomb equilibration and adiabatic expansion. In contrast, the emission-measure-weighted average temperature for the northeast region is 0.77 ± 0.04 keV, which is significantly lower than the value inferred from the shock velocity. We fit 1D evolutionary models for the shock in the southern rim and northeast region, using the measured radius and propagation velocity into constant density and power-law profile circumstellar media. We find good agreement with the age of ∼2500 yr derived from optical expansion measurements for explosion energies of 1.5–3.0 × 10⁵¹erg, ejecta masses of 2–6M_⊙, and ambient medium densities of ∼0.33–0.66 amu cm⁻³in the south and ∼0.01–0.02 amu cm⁻³in the northeast assuming a constant density medium. These results are consistent with previous studies that suggested the progenitor of N132D was an energetic supernova that exploded into a preexisting cavity. 

Abstract We present proper motion measurements of the oxygen-rich ejecta of the LMC supernova remnant N132D using two epochs of Hubble Space Telescope Advanced Camera for Surveys data spanning 16 years. The proper motions of 120 individual knots of oxygen-rich gas were measured and used to calculate a center of expansion (CoE) of α = 5 h 25 m 01.ˢ71 and δ = −69°38′41.″64 (J2000) with a 1 σ uncertainty of 2.″90. This new CoE measurement is 9.″2 and 10.″8 from two previous CoE estimates based on the geometry of the optically emitting ejecta. We also derive an explosion age of 2770 ± 500 yr, which is consistent with recent age estimates of ≈2500 yr made from 3D ejecta reconstructions. We verified our estimates of the CoE and age using a new automated procedure that detected and tracked the proper motions of 137 knots, with 73 knots that overlap with the visually identified knots. We find that the proper motions of the ejecta are still ballistic, despite the remnant’s age, and are consistent with the notion that the ejecta are expanding into an interstellar medium cavity. Evidence for explosion asymmetry from the parent supernova is also observed. Using the visually measured proper motion measurements and corresponding CoE and age, we compare N132D to other supernova remnants with proper motion ejecta studies.