(a) The spectral profile plot for the H26α and H30α lines. The peak intensity for each spectral channel in the Band 6 and 7 data cubes was extracted as the amplitude from the centroid fit. Velocities are measured in the LSR reference frame in km s⁻¹, and for both lines the velocity resolution is 1.26 km s⁻¹. (b) The spatial distributions of H30α and H26α maser emission obtained by fitting elliptical Gaussians to the data cubes for the two recombination lines. Error bars include the standard deviation from the centroid fit and error contribution from the bandpass calibration (see the text for details). The H26α and the H30α distributions are offset from the position of the Band 7 and 6 continuum, respectively.