We use absolutely calibrated data from the ARCADE 2 flight in July 2006 to model Galactic emission at frequencies 3 , 8 , and 10 GHz .
The spatial structure in the data is consistent with a superposition of free-free and synchrotron emission .
Emission with spatial morphology traced by the Haslam 408 MHz survey has spectral index \beta _ { synch } = -2.5 \pm 0.1 , with free-free emission contributing 0.10 \pm 0.01 of the total Galactic plane emission in the lowest ARCADE 2 band at 3.15 GHz .
We estimate the total Galactic emission toward the polar caps using either a simple plane-parallel model with \csc ( |b| ) dependence or a model of high-latitude radio emission traced by the COBE/FIRAS map of C ii emission .
Both methods are consistent with a single power-law over the frequency range 22 MHz to 10 GHz , with total Galactic emission towards the north polar cap T _ { Gal } = 0.498 \pm 0.028 K and spectral index \beta = -2.55 \pm 0.03 at reference frequency 1 GHz .
The well calibrated ARCADE 2 maps provide a new test for spinning dust emission , based on the integrated intensity of emission from the Galactic plane instead of cross-correlations with the thermal dust spatial morphology .
The Galactic plane intensity measured by ARCADE 2 is fainter than predicted by models without spinning dust , and is consistent with spinning dust contributing 0.4 \pm 0.1 of the Galactic plane emission at 22 GHz .