New Maser Emission from Nonmetastable Ammonia in NGC 7538
  We present the first interferometric observations at 18.5 GHz of IRS 1 in NGC
7538. These observations include images of the nonmetastable ^{14}NH_3 (9,6)
masers with a synthesized beam of 2 arcseconds and images of the continuum
emission with a synthesized beam of 150 milliarcseconds. Of the maser emission,
the previously known feature near v_LSR = -60 km/s is spectrally resolved into
at least two components and we observe several new maser emission features near
v_LSR = -57 km/s. The new maser emission near -57 km/s lies 250 +/- 90
milliarcseconds northwest of the maser emission near -60 km/s. All of the
masers are angularly unresolved indicating brightness temperatures T_B > 2000
K. We are also able to conclusively associate the ammonia masers with the
position of IRS 1. The excitation of these rare ammonia masers is discussed in
the context of the rich maser environment of IRS 1.
