| DOI | Resolve DOI: https://doi.org/10.1111/j.1365-2966.2012.20970.x |
|---|
| Author | Search for: Shimwell, T.W.; Search for: Barker, R.W.; Search for: Biddulph, P.; Search for: Bly, D.; Search for: Boysen, R.C.; Search for: Brown, A.R.; Search for: Brown, M.L.; Search for: Clementson, C.; Search for: Crofts, M.; Search for: Culverhouse, T.L.; Search for: Czeres, J.; Search for: Dace, R.J.; Search for: Davies, M.L.; Search for: D'Alessandro, R.; Search for: Doherty, P.; Search for: Duggan, K.; Search for: Ely, J.A.; Search for: Felvus, M.; Search for: Feroz, F.; Search for: Flynn, W.; Search for: Franzen, T.M.O.; Search for: Geisbüsch, J.1; Search for: Génova-Santos, R.; Search for: Grainge, K.J.B.; Search for: Grainger, W.F.; Search for: Hammett, D.; Search for: Hobson, M.P.; Search for: Holler, C.M.; Search for: Hurley-Walker, N.; Search for: Jilley, R.; Search for: Kaneko, T.; Search for: Kneissl, R.; Search for: Lancaster, K.; Search for: Lasenby, A.N.; Search for: Marshall, P.J.; Search for: Newton, F.; Search for: Norris, O.; Search for: Northrop, I.; Search for: Odell, D.M.; Search for: Olamaie, M.; Search for: Perrott, Y.C.; Search for: Pober, J.C.; Search for: Pooley, G.G.; Search for: Pospieszalski, M.W.; Search for: Quy, V.; Search for: Rodríguez-Gonzálvez, C.; Search for: Saunders, R.D.E.; Search for: Scaife, A.M.M.; Search for: Schammel, M.P.; Search for: Schofield, J.; Search for: Scott, P.F.; Search for: Shaw, C.; Search for: Smith, H.; Search for: Titterington, D.J.; Search for: Velić, M.; Search for: Waldram, E.M.; Search for: West, S.; Search for: Wood, B.A.; Search for: Yassin, G.; Search for: Zwart, J.T.L. |
|---|
| Affiliation | - National Research Council of Canada. NRC Herzberg Institute of Astrophysics
|
|---|
| Format | Text, Article |
|---|
| Abstract | We present an interesting Sunyaev-Zel'dovich (SZ) detection in the first of the Arcminute Microkelvin Imager (AMI) 'blind', degree-square fields to have been observed down to our target sensitivity of. In follow-up deep pointed observations the SZ effect is detected with a maximum peak decrement greater than eight times the thermal noise. No corresponding emission is visible in the ROSAT all-sky X-ray survey and no cluster is evident in the Palomar all-sky optical survey. Compared with existing SZ images of distant clusters, the extent is large (≈10arcmin) and complex; our analysis favours a model containing two clusters rather than a single cluster. Our Bayesian analysis is currently limited to modelling each cluster with an ellipsoidal or spherical β model, which does not do justice to this decrement. Fitting an ellipsoid to the deeper candidate we find the following. (a) Assuming that the Evrard et al. approximation to Press & Schechter correctly gives the number density of clusters as a function of mass and redshift, then, in the search area, the formal Bayesian probability ratio of the AMI detection of this cluster is 7.9 × 10 4:1; alternatively assuming Jenkins et al. as the true prior, the formal Bayesian probability ratio of detection is 2.1 × 10 5:1. (b) The cluster mass is (c) Abandoning a physical model with number density prior and instead simply modelling the SZ decrement using a phenomenological β model of temperature decrement as a function of angular distance, we find a central SZ temperature decrement of K - this allows for cosmic microwave background primary anisotropies, receiver noise and radio sources. We are unsure if the cluster system we observe is a merging system or two separate clusters. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS. |
|---|
| Publication date | 2012 |
|---|
| In | |
|---|
| Language | English |
|---|
| Peer reviewed | Yes |
|---|
| NPARC number | 21269439 |
|---|
| Export citation | Export as RIS |
|---|
| Report a correction | Report a correction (opens in a new tab) |
|---|
| Record identifier | 665e04e8-51d1-4f35-b944-4acbe55e99f3 |
|---|
| Record created | 2013-12-12 |
|---|
| Record modified | 2020-04-21 |
|---|
