The QUIJOTE-MFI Northern Hemisphere Wide-Survey has provided maps of the sky
above declinations
−30∘ at 11, 13, 17 and 19
GHz. These data are
combined with ancillary data to produce Spectral Energy Distributions in
intensity in the frequency range 0.4--3\,000
GHz on a sample of 52 candidate
compact sources harbouring anomalous microwave emission (AME). We apply a
component separation analysis at 1
∘ scale on the full sample from which
we identify 44 sources with high AME significance. We explore correlations
between different fitted parameters on this last sample. QUIJOTE-MFI data
contribute to notably improve the characterisation of the AME spectrum, and its
separation from the other components. In particular, ignoring the 10--20\,GHz
data produces on average an underestimation of the AME amplitude, and an
overestimation of the free-free component. We find an average AME peak
frequency of 23.6
± 3.6
GHz, about 4
GHz lower than the value
reported in previous studies. The strongest correlation is found between the
peak flux density of the thermal dust and of the AME component. A mild
correlation is found between the AME emissivity (
AAME/τ250) and
the interstellar radiation field. On the other hand no correlation is found
between the AME emissivity and the free-free radiation Emission Measure. Our
statistical results suggest that the interstellar radiation field could still
be the main driver of the intensity of the AME as regards spinning dust
excitation mechanisms. On the other hand, it is not clear whether spinning dust
would be most likely associated with cold phases of the interstellar medium
rather than with hot phases dominated by free-free radiation.