AMI-CL J0300+2613: a Galactic anomalous-microwave-emission ring masquerading as a galaxy cluster

Feroz, Farhan; Grainge, Keith J. B.; Hobson, Michael P.; Pooley, Guy G.; Saunders, Richard D. E.; Scaife, Anna M. M.; Scott, Paul F.; Shimwell, Timothy W.; Titterington, David J.; Waldram, Elizabeth M.; Green, David A.; Perrott, Yvette C.; Schammel, Michel P.; Cantwell, Therese M.; Carey, Steve H.; Elwood, Patrick J.; Javid, Kamran; Jin, Terry Z.; Razavi-Ghods, Nima; Rumsey, Clare

United Kingdom, Netherlands

Abstract

The Arcminute Microkelvin Imager (AMI) carried out a blind survey for galaxy clusters via their Sunyaev-Zel'dovich effect decrements between 2008 and 2011. The first detection, known as AMI-CL J0300+2613, has been reobserved with AMI equipped with a new digital correlator with high dynamic range. The combination of the new AMI data and more recent high-resolution sub-mm and infrared maps now shows the feature in fact to be a ring of positive dust-correlated Galactic emission, which is likely to be anomalous microwave emission (AME). If so, this is the first completely blind detection of AME at arcminute scales.

2018 Monthly Notices of the Royal Astronomical Society
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