Searching for anomalous microwave emission in nearby galaxies. K-band observations with the Sardinia Radio Telescope

We observed four nearby spiral galaxies (NGC 3627, NGC 4254, 4736 and 5055) in the K band with 64-m Sardinia Radio Telescope, aim of detecting Anomalous Microwave Emission (AME), a radiation component presumably due to spinning dust grains, so far Milky Way handful other only (most notably, M 31). mapped at 18.6 24.6 GHz studied their global photometry together radio-continuum data from literature, order find AME as emission excess synchrotron thermal components. upper limits for AME. These non-detections, are nevertheless consistent average emissivity few detections: it is $\epsilon^\mathrm{AME}_{\mathrm{30~GHz}} = 2.4\pm0.4 \times 10^{-2}$ MJy sr$^{-1}$ (M$_\odot$ pc$^{-2}$)$^{-1}$ units surface density (equivalently, $1.4\pm0.2 10^{-18}$ Jy (H cm$^{-2}$)$^{-1}$ H column density). finally suggest search quiescent spirals relatively low radio luminosity, such M~31.