Far-Ultraviolet Observations of the Monogem Ring

Abstract

We present the results of far-ultraviolet (FUV) observations of the Monogem ring made with the FIMS/SPEAR instrument. The global map constructed from the C IV λλ1548, 1550 emission lines presents clear evidence of the interaction of the Monogem ring with the ambient medium. The image shows a half-ring feature in the low-latitude region, with its peak along the distorted boundary of the X-ray ring, where hot gas is in direct contact with the newly found Hα ring (the Gemini Hα ring) centered at (l, b) ~ (191.5°, +5.0°). Only a small portion of the X-ray ring is bright in C IV in the high-latitude region, where hot gas is seen to extend to a great distance from the ring. We have also detected other ionic emission lines in several regions of the Monogem ring, such as C III λ977, O VI λλ1032, 1038, Si II* λ1533, He II λ1640, and O III] λ1666.