Description of source "G10.34-0.14" from Cyganowski et al. (2009)


This EGO is located north of the MIR-bright complex in the W31 molecular cloud described above (Section 3.8.1), and is located in an IRDC. The extended 4.5 µm emission of this EGO is predominantly linear, along a NW–SE axis, with an additional patch of more diffuse 4.5 µm emission ∼15 arcsec to the SE (Figures 1(b) and 5(b)). The spatial relationship of the Class I CH3OH masers and the extended 4.5 µm emission is complex; this is also true of the velocity distribution of the 44 GHz masers.

The most coherent features are (from E to W in the left panel of Figure 5(b)): (1) a concentration of slightly blueshifted masers coincident with the diffuse 4.5 µm emission to the SE; (2) two lines of blueshifted masers to the south of the EGO, roughly parallel to each other and ∼5arcsec apart; and (3) a concentration of redshifted masers near the NW edge of the linear 4.5 µm emission.

The velocity distribution of the 6.7 GHz CH3OH maser emission is also complex. To the north is a dense concentration of masers spanning ∼9 km s−1 (v ∼7–16 km s−1, Table 7). To the south are two linear features, one comprised predominantly of redshifted masers (oriented N–S), and the other of blueshifted masers (oriented NE–SW). This 6.7 GHz CH3OH maser was previously reported by Walsh et al. (1998), but over a much tnoarvrower velocity range (v = 14.3–16.7 km s−1, compared = 3.6–18 km s−1 in our survey, Table 9). The 6.7 GHz maser group is located near redshifted 44 GHz CH3OH maser emission.