Molecular Environment of the Supernova Remnant Ic 443: Discovery of the Molecular Shells Surrounding the Remnant

Abstract

We have carried out 12 CO, 13 CO, and C 18 O observations toward the mixed morphology supernova remnant (SNR) IC 443. The observations cover a 1.• 5 × 1.• 5 area and allow us to investigate the overall molecular environment of the remnant. Some northern and northeastern partial shell structure of CO gas is around the remnant. One of the partial shells, about 5 extending beyond the northeastern border of the remnant's bright radio shell, seems to just confine the faint radio halo. On the other hand, some faint CO clumps can be discerned along the eastern boundary of the faint remnant's radio halo. Connecting the eastern CO clumps, the northeastern partial shell structures, and the northern CO partial shell, we can see that a half molecular ring structure appears to surround the remnant. The LSR velocity of the half-ring structure is in the range of −5 km s −1 to −2 km s −1 , which is consistent with that of the −4 km s −1 molecular clouds. We suggest that the half-ring structure of the CO emission at V LSR ∼ −4 km sis associated with the SNR. The structures are possibly swept up by the stellar winds of SNR IC 443's massive progenitor. Based on the Wide-field Infrared Survey Explorer and the Two Micron All Sky Survey near-IR database, 62 young stellar object (YSO) candidates are selected within the radio halo of the remnant. These YSO candidates concentrated along the boundary of the remnant's bright radio shell are likely to be triggered by the stellar winds from the massive progenitor of SNR IC 443.

Molecular Gas toward the Gemini OB1 Molecular Cloud Complex. I. Observation Data

“…IC 443 is a supernova remnant (SNR) associated with the GEM OB1 association, and as Su et al (2014) have already presented an up-to-date analysis of its properties, it will not be investigated in this paper. Figure 1 presents an integrated map of CO and its other two isotope molecules.…”

A New Look at the Integrated Radio/Microwave Continuum Spectrum of Galactic Supernova Remnant Ic 443

“…In fact, it is associated with a dense giant molecular cloud (MC) near the Gem OB1 association (Cornett, Chin & Knapp 1977;Humphreys 1978;Heiles 1984). The SNR/MC interaction in IC 443 is very well studied (Hoffman et al 2003;Shinn et al 2011;Su et al 2014;Kilpatrick, Bieging & Rieke 2016, and references therein). Actually, the physical conditions toward this SNR are very well suited for all known shock interaction tracers that are traditionally used to identify SNR/MC interactions (broadened CO emission, OH 1720 MHz maser, HCO + , HCN, H 2 emission, etc).…”

“…Actually, it is proposed that the SNR has probably been formed inside a dense medium (possibly evolved inside the preexisting wind-blown bubble) and then broke out to the adjacent rarefied medium. In addition, Su et al (2014) reported infrared detection of sixty-two young stellar object (YSO) candidates (disk-bearing young stars: 24 of Class I and 38 of Class II), mainly concentrated along the boundary of the remnant's bright radio shell (but absent in the southwestern breakout portion of the SNR), and suggested that they are likely to be triggered by the stellar wind from the massive progenitor of SNR IC 443.…”

Molecular Environments of Three Large Supernova Remnants in the Third Galactic Quadrant: G205.5+0.5, G206.9+2.3, and G213.0–0.6

“…To date, three large-scale, systematic CO surveys were performed to investigate the SNR-MC association (Huang & Thaddeus 1986;Jeong et al 2012;Kilpatrick et al 2016). Recently, several individual SNR-MC systems were also investigated using CO lines (e.g., SNR W44 by Anderl et al 2014; SNR Cassiopeia A by Kilpatrick et al 2014; SNR IC 443 by Su et al 2014a; SNR G22.7−0.2 by Su et al 2014b; SNR G127.1+0.5 by Zhou et al 2014; SNR G18.8+0.3 by Paron et al 2015; SNR G357.7+0.3 by Rho et al 2017; SNR RCW 86 by Sano et al 2016; SNR Tycho by Zhou et al 2016a andChen et al 2016; and SNR HB 3 by Zhou et al 2016b). Nevertheless, few studies have been conducted to investigate the SNRs' molecular environment in the third Galactic quadrant.…”