NH₃ spectra showing a new maser component near a local standard of rest (LSR) velocity of 45 km s^-1. Note the slight velocity shifts in the (6, 6) and (7, 6) emission as a function of time (see Sect. 4.5). Less prominent quasi-thermal emission is centered near 60 km s^-1. All spectra were taken at α_B1950 = 19^h21^m2219, δ_B1950 =  + 14°25^m17.0′′, corresponding to α_J2000 = 19^h23^m3983, δ_J2000 = +14°31^m10.1′′. For telescope beam sizes and channel spacings, see Table 1.