Brightness temperatures and spectral indices across the entire radius of A1 and A2, illustrating their emission patterns. Upper right and left panels: brightness temperatures at 1.2 mm, 2.1 mm, and 9.1 mm of A1 and A2, respectively. Lower right and left panels: spectral indices between 9.1–2.1 mm and 2.1–1.2 mm of A1 and A2, respectively. In the inner parts of the A1 source, some free-free emission might be present at 9.1 mm. Moreover, the brightness temperature in A1 at 1.2 mm is lower than that at 2.1 mm, which, as seen from the spectral index, might indicate very optically thick emission at those wavelengths and small dust particles (<1 mm). We only considered the statistical uncertainties for the brightness temperature and spectral index.