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arXiv · 1709.05136

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

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

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Yvette C. Perrott, Therese M. Cantwell, Steve H. Carey, Patrick J. Elwood, Farhan Feroz, Keith J. B. Grainge, David A. Green, Michael P. Hobson, Kamran Javid, Terry Z. Jin, Guy G. Pooley, Nima Razavi-Ghods, Clare Rumsey, Richard D. E. Saunders, Anna M. M. Scaife, Michel P. Schammel, Paul F. Scott, Timothy W. Shimwell, David J. Titterington, Elizabeth M. Waldram. 2017-09-15. AMI-CL J0300+2613: a Galactic anomalous-microwave-emission ring masquerading as a galaxy cluster. https://doi.org/10.1093/mnras%2Fstx2421

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