2006/01/31 by B. M. Gaensler, S. Chatterjee, Shami Chatterjee +6 · 5 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Pulsars and Gravitational Waves Research #astro-ph
paper · pdf · doi:10.1086/506246
published as Astrophys.J.648:1037-1042,2006 · 8 pages, including 3 color EPS figure. Expaneded to include new figures, plus discussion of the association between the pulsar and the supernova remnant. ApJ, in press
arxiv created 2006/05/25 · openalex publication_date 2006/09/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
We present a deep observation with the Chandra X-Ray Observatory of the neutron star bow shock G189.22+2.90 in the supernova remnant (SNR) IC 443. Our data confirm the cometary morphology and central point source seen previously, but also reveal considerable new structure. Specifically, we find that the X-ray nebula consists of two distinct components: a "tongue" of bright emission close to the neutron star, enveloped by a larger, fainter "tail." We interpret the tongue and tail as delineating the termination shock and the postshock flow, respectively, as previously identified also in the pulsar bow shock G359.23-0.82 ("the Mouse"). However, for G189.22+2.90 the tongue is much less elongated than for the Mouse, while the tail is much broader. These differences are consistent with the low Mach number, M ≲ 2, expected for a neutron star moving through the hot gas in a SNR's interior, supporting the case for a physical association between G189.22+2.90 and IC 443. We resolve the standoff distance between the star and the head of the bow shock, which allows us to estimate a space velocity for the neutron star of ~230 km s -1 , independent of distance. We detect thermal emission from the neutron star surface at a temperature of 102 ± 22 eV, which is consistent with the age of SNR IC 443 for standard neutron star cooling models. We also identify two compact knots of hard emission located 1''-2'' north and south of the neutron star.