Velocity fields of seven inversion transitions of NH₃ as well as the CH₃OH line, as measured toward NGC 7538 IRS1 with the JVLA B-array. The 1st moment maps (images) are overlaid on the total intensity 0th moment maps (contours). Colors indicate V_LSR in km s^-1. The images were constructed with a 0.′′04 pixel for all transitions. The contours represent factors 1, 3, 6, 12,... (afterwards, they are spaced by 10) of −20 mJy beam^-1, for all transitions. A flux cutoff of −7 to −11 mJy beam^-1 (~ 3 − 4σ) was used for various transitions, except the (12, 12) and (14, 14) transitions, for which the cutoff was set to 20 mJy beam^-1. We note that different velocity scales are used in different panels; in particular, color scales are expanded towards higher velocities with increasing quantum number to clearly show the redshifted absorption, e.g., NH₃ (13, 13). All transitions show a velocity gradient NE-SW from NGC 7538 IRS1, at approximately 30−40° (depending on transition), with the exception of the (14, 14) line. The synthesized beams (0.′′17−0.′′33) are shown in the lower left corner of each panel (see Table 1).