%0 Journal Article
%T A Characterization of the Diffuse Galactic Emissions in the Anticenter of the Galaxy
%A L. Fauvet
%A J. F. Macías-Pérez
%A S. R. Hildebrandt
%A F.-X. Désert
%J Advances in Astronomy
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/746020
%X Using the Archeops and WMAP data, we perform a study of the anticenter Galactic diffuse emissions—thermal dust, synchrotron, free-free, and anomalous emissions—at degree scales. The high-frequency data are used to infer the thermal dust electromagnetic spectrum and spatial distribution allowing us to precisely subtract this component at lower frequencies. After subtraction of the thermal dust component, a mixture of standard synchrotron and free-free emissions does not account for the residuals at these low frequencies. Including the all-sky 408？MHz Haslam data we find evidence for anomalous emission with a spectral index of ？2.5 in units. However, we are not able to provide coclusion regarding the nature of this anomalous emission in this region. For this purpose, data between 408？MHz and 20？GHz covering the same sky region are needed. 1. Introduction The anomalous microwave emission (AME in the following) is an important contributor of the Galactic diffuse emissions in the range from 20 to 60？GHz. It was first observed by [1, 2] and then identified by [3] as free-free emission from electrons with temperature ？K. Draine and Lazarian [4] argued that AME may result from electric dipole radiation due to small rotating grains, the so-called spinning dust. Models of the spinning dust emission [5] show an electromagnetic spectra peaking at around 20–50？GHz being able to reproduce the observations [6–13]. The initial spinning dust model has been refined regarding the shape and rotational properties of the dust grains [14–17]. An alternative explanation of AME was proposed by Draine and Lazarian [18] based on magnetic dipole radiation arising from hot ferromagnetic grains. This kind of models associated to single domain predict polarization fraction much bigger than the electric dipole ones [19]. Original models have been mainly ruled out by many studies [10, 20–23] although modern variants of those may still be of interest (B. Draine private communication). Correlation between microwave and infrared maps, mainly dominated by dust thermal emission [24], was observed for various experiments, for example, on COBE/DMR [2, 25], OVRO [3], Saskatoon [1], survey at 19？GHz [26], and Tenerife [27]. Similar signal was found in small region by [6] and in some molecular clouds based on data from COSMOSOMAS [8, 28], AMI (AMI Consortium [29, 30]), CBI [10, 31], VSA [13], and Planck [32]. Recent studies based on several sets of data [33] found similar results. Independently, Bennett et al. [34] proposed an alternative explanation of AME based on flat-spectrum synchrotron
%U http://www.hindawi.com/journals/aa/2013/746020/