Far-ultraviolet cooling features of the Antlia supernova remnant

Abstract

We present far-ultraviolet observations of the Antlia supernova remnant obtained with Far-Ultraviolet Imaging Spectrograph (FIMS, also called SPEAR). The strongest lines observed are C IV lambda lambda 1548, 1551 and C III lambda 977. The C IV emission of this mixed-morphology supernova remnant shows a clumpy distribution, and the line intensity is nearly constant with radius. The C III lambda 977 line, although too weak to be mapped over the whole remnant, is shown to vary radially. The line intensity peaks at about half the radius and drops at the edge of the remnant. Both the clumpy distribution of C IV and the rise in the C IV to C III ratio toward the edge suggest that central emission is from evaporating cloudlets rather than thermal conduction in a more uniform, dense medium.