Previous continuum observations from the MUSTANG camera on the Green Bank Telescope (GBT) of the nearby star-forming filament OMC 2/3 found elevated emission at 3.3 mm relative to shorter wavelength data. As a consequence, the inferred dust emissivity index obtained from modified black body dust spectra was considerably lower than what is typically measured on $sim 0.1 , {rm pc}$ scales in nearby molecular clouds. Here we present new observations of OMC 2/3 collected with the MUSTANG-2 camera on the GBT which confirm this elevated emission. We also present for the first time sensitive 1 cm observations made with the Ka-band receiver on the GBT which also show higher than expected emission. We use these observations--- along with Herschel, JCMT, Mambo, and GISMO data--- to assemble spectral energy distributions (SEDs) of a variety of structures in OMC 2/3 spanning the range $160 , {rm mu m}$ to $1 , {rm cm}$. The data at 2 mm and shorter are generally consistent with a modified black body spectrum and a single value of $beta sim 1.6$. The 3 mm and 1 cm data, however, lie well above such an SED. The spectrum of the long wavelength excess is inconsistent with both free-free emission and standard Spinning Dust models for Anomalous Microwave Emission (AME). The 3 mm and 1 cm data could be explained by a flatter dust emissivity at wavelengths shorter than 2 mm, potentially in concert with AME in some regions.
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