Left to right: combined VLA+GBT integrated intensities of the observed ammonia (1,1) and (2,2) lines, computed between 42 and 47 km. The white dotted contour marks the significance level of the integrated intensity of each line at the 3σ_I level, where σ_I is the integrated intensity uncertainty (Mangum & Shirley 2015). The white solid contours show the infrared extinction contours (Kainulainen & Tan 2013) starting from A_V = 30 mag and progressing inwards in steps of 30 mag. The open and filled red stars denote the positions of the Herschel sources from Nguyen Luong et al. (2011) below and above 20 M_⊙, respectively, while the open diamonds mark the location of cores from (2009, 2012).