We study the anomalous microwave emission ( AME ) in the Lynds Dark Nebula ( LDN ) 1780 on two angular scales .
Using available ancillary data at an angular resolution of 1 degree , we construct an SED between 0.408 GHz to 2997 GHz .
We show that there is a significant amount of AME at these angular scales and the excess is compatible with a physical spinning dust model .
We find that LDN 1780 is one of the clearest examples of AME on 1 degree scales .
We detected AME with a significance > 20 \sigma .
We also find at these angular scales that the location of the peak of the emission at frequencies between 23–70 GHz differs from the one on the 90–3000 GHz map .
In order to investigate the origin of the AME in this cloud , we use data obtained with the Combined Array for Research in Millimeter-wave Astronomy ( CARMA ) that provides 2 arcmin resolution at 30 GHz .
We study the connection between the radio and IR emissions using morphological correlations .
The best correlation is found to be with MIPS 70 \mu m , which traces warm dust ( T \sim 50 K ) .
Finally , we study the difference in radio emissivity between two locations within the cloud .
We measured a factor \approx 6 of difference in 30 GHz emissivity .
We show that this variation can be explained , using the spinning dust model , by a variation on the dust grain size distribution across the cloud , particularly changing the carbon fraction and hence the amount of PAHs .