Abstract: We present new intensity and polarization maps obtained with the QUIJOTE experiment towards the Galactic regions W49, W51 and IC443, covering the frequency range from 10 to 20-GHz at -1deg angular resolution, with a sensitivity in the range 35-79 uK Kbeam-1 for total intensity and 13-23 uK Kbeam-1 for polarization. For each region, we combine QUIJOTE maps with ancillary data at frequencies ranging from 0.4 to 3000 GHz, reconstruct the spectral energy distribution and model it with a combination of known foregrounds. We detect anomalous microwave emission (AME) in total intensity towards W49 at 4.7 and W51 at 4.0 with peak frequencies vAME=(20.0±1.4)GHz and vAME=(17.7±3.6)GHz, respectively; this is the first detection of AME towards W51. The contamination from ultracompact HII regions to the residual AME flux density is estimated at 10 per cent in W49 and 5 per cent in W51, and does not rule out the AME detection. The polarized SEDs reveal a synchrotron contribution with spectral indices as = -0.67 ± 0.10 in W49 and as = -0.51 ± 0.07 in W51, ascribed to the diffuse Galactic emission and to the local supernova remnant, respectively. Towards IC443 in total intensity we measure a broken power-law synchrotron spectrum with cut-off frequency v0,s=(114±73)GHz, in agreement with previous studies; our analysis, however, rules out any AME contribution which had been previously claimed towards IC443. No evidence of polarized AME emission is detected in this study.

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