Subarcsecond Imaging of 3C 123: 108 GHz Continuum Observations of the Radio Hot Spots

We present the results of sub-arcsecond 108 GHz continuum interferometricobservations toward the radio luminous galaxy 3C123. Using multi-arrayobservations, we utilize the high u,v dynamic range of the BIMA millimeterarray to sample fully spatial scales ranging from 0.5" to 50". This allows usto make one-to-one comparisons of millimeter-wavelength emission in the radiolobes and hotspots to VLA centimeter observations at 1.4, 4.9, 8.4, and 15 GHz.At 108 GHz, the bright, eastern double hotspot in the southern lobe isresolved. This is only the second time that a multiple hotspot region has beenresolved in the millimeter regime. We model the synchrotron spectra of thehotspots and radio lobes using simple broken power-law models with high energycutoffs, and discuss the hotspot spectra and their implications for models ofmultiple hotspot formation.Comment: 16 pages, 3 Figures, ApJ Accepte