SED of PM 1-322. Top: representation in log–log scale that clearly indicates an IR excess. Bottom: λF_λ representation that demonstrates that most of the energy is in fact radiated at IR wavelengths. Observations are indicated by the purple circles with error-bars. The green and blue lines denote, respectively, a simple two black-body fit and a three black-body fit to the data. The small dark-blue points in the upper plot represent a smoothed flux calibrated spectrum from Sect. 6.1.