Published in

Oxford University Press (OUP), Monthly Notices of the Royal Astronomical Society, 4(424), p. 2676-2685

DOI: 10.1111/j.1365-2966.2012.21358.x

Links

Tools

Export citation

Search in Google Scholar

Template fitting of WMAP 7-year data: anomalous dust or flattening synchrotron emission?

Journal article published in 2012 by Mw W. Peel ORCID, C. Dickinson ORCID, Rd D. Davies, Aj J. Banday, Tr R. Jaffe, Jl L. Jonas
This paper is made freely available by the publisher.
This paper is made freely available by the publisher.

Full text: Download

Green circle
Preprint: archiving allowed
Green circle
Postprint: archiving allowed
Green circle
Published version: archiving allowed
Data provided by SHERPA/RoMEO

Abstract

Anomalous microwave emission at 20-40 GHz has been detected across our Galactic sky. It is highly correlated with thermal dust emission and hence it is thought to be due to spinning dust grains. Alternatively, this emission could be due to synchrotron radiation with a flattening (hard) spectral index. We cross-correlate synchrotron, free-free and thermal dust templates with the Wilkinson Microwave Anisotropy Probe (WMAP) 7-year maps using synchrotron templates at both 408 MHz and 2.3 GHz to assess the amount of flat synchrotron emission that is present, and the impact that this has on the correlations with the other components. We find that there is only a small amount of flattening visible in the synchrotron spectral indices by 2.3 GHz, of around Δβ ≈ 0.05, and that the significant level of dust-correlated emission in the lowest WMAP bands is largely unaffected by the choice of synchrotron template, particularly at high latitudes (it decreases by only ˜7 per cent when using 2.3 GHz rather than 408 MHz). This agrees with expectation if the bulk of the anomalous emission is generated by spinning dust grains. ; DOI: 10.1111/j.1365-2966.2012.21358.x; eprintid: arXiv:1112.0432