a) Millimeter mass vs. distance from “center”. We mark mm sources with no IR counterpart with dark red circles; Class 0/I protostar candidates with red squares; and flat-spectrum SED sources with light red diamonds. The best fit power-law (gray line) has an index of − 1.4 ± 0.2. We note that to perform this power-law fit, we removed the two sources with distances d < 2000 au from the center (points in the lower left). The “center” refers to the plus-sign in Fig. 1, and is discussed in Sect. 4.1. b) Mass vs. N₂ H⁺ integrated intensity. c) Mass vs. N₂H⁺ velocity dispersion. Here “mass” refers to mass of dust and gas based on 1.3 mm continuum emission and the calculation described in Sect. 3.3. N₂ H⁺ integrated intensity and velocity dispersion are measured at each position given in Table A.1.