X-ray Evolution of SNR 1987A: The Radial Expansion

• Published in: The Astrophysical journal Vol. 703; no. 2; pp. 1752 - 1759
• Main Authors: Racusin, Judith L, Park, Sangwook, Zhekov, Svetozar, Burrows, David N, Garmire, Gordon P, McCray, Richard
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01-10-2009; IOP
• Subjects: Astronomy; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BINARY STARS; COSMIC RADIO SOURCES; Earth, ocean, space; ERUPTIVE VARIABLE STARS; EVOLUTION; Exact sciences and technology; EXPANSION; STARS; SUPERNOVA REMNANTS; SUPERNOVAE; VARIABLE STARS; supernovae: individual (SN 1987A); Supernova remnants; Supernovae; X-rays: ISM
• ISSN: 0004-637X; 1538-4357
• DOI: 10.1088/0004-637X/703/2/1752

We present the evolution of the radial expansion of SNR 1987A as measured using Chandra X-ray observations taken over the last 10 years. To characterize the complex structure of the remnant and isolate the expansion measurement, we fit the images to several empirical models including: a simple circular torus, a torus with bilateral lobes, and a torus with four tangentially extended lobes. We discuss the results of this measure in the context of the overall evolution of the supernova remnant, for which we believe we have measured the end of the free expansion phase and its transition to the adiabatic phase (at least along the equatorial ring). The timing of this event is in agreement with early predictions of the remnant evolution.