Publication Date:
2011-08-18
Description:
New spectroscopic observations of four filaments in 3C 58, three of which appear close to the remnant's radio center, are described. Observed line intensities and radial velocities are presented which indicate a high radial expansion velocity for the object and nearly zero radial velocities for filaments located along the remnant's edge. Large velocities are present nearer the remnant's center up to a maximum of about 900 km/s. These velocities strongly support the identification of 3C 58 as the remnant of the historical supernova seen in AD 1181. A crude estimate of the reddening of the object is made. The observed H-alpha/H-beta ratio of about six suggests only a modest amount of extinction. The object is unlikely to possess a mean expansion velocity of 10,000 km/s over 800 yr, and a previously estimated distance to the object of about 8 kpc is thus improbable.
Keywords:
ASTROPHYSICS
Type:
Astrophysical Journal, Part 2 - Letters to the Editor (ISSN 0004-637X); 270; July 15
Format:
text
