Early Science with AMI

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Early Science with AMI

• Jonathan Zwart
• jtlz2_at_mrao.cam.ac.uk

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Overview

• Case Study Abell 1914
• Observing strategy science goals
• Early cluster targets
• Survey plans

19 March 2006
Jonathan Zwart, Cavendish Astrophysics
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A1914 228 Hours with Ryle
19 March 2006
Jonathan Zwart, Cavendish Astrophysics
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A1914 34 Hours with AMI
Long baselines
Short baselines (after radio sources removed)
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• Only 7 (/10) antennas
• 18 point sources subtracted
• ? Need for source subtraction
• astro-ph/0509215 (MNRAS accepted)

19 March 2006
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Observing Strategy

• Known clusters
• Initial blind surveys
• Surveys of equatorial fields (need LA)
• Joint fields (AMiBA, SZA, UKIDSS)

19 March 2006
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Early Cluster Targets

• Abell (optical) NORAS (X-ray)
• MACS (X-ray, Ebeling et al. 2000)
• High-z candidates
• Ryle source survey (2004)
• 4 days for each of 100 lucky targets

19 March 2006
Jonathan Zwart, Cavendish Astrophysics
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NORAS-Selected Clusters

• Selection criteria
• LX gt 6.81044 erg s-1
• z gt 0.1
• Calibrate scaling relations LT, M, etc
• X-ray ? ?g, H0

A263 10 hours z 0.3 (Natasha Hurley-Walker)
19 March 2006
Jonathan Zwart, Cavendish Astrophysics
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MACS-Selected Clusters

• Selection criteria
• LX gt 1045 erg s-1
• z gt 0.5
• Evolution of scaling relations with z
• X-ray ? ?g (z), H0, q0

MACS 071737 8 hours z 0.545
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Blind Surveys

• Wedding cake
• 10 ? deep survey (1 year)
• 100 ? shallow survey (6 months)
• Evolution of cluster population, N(m,z)
• Some experimenting with z from SZ alone
• But for now obtain redshifts independently

19 March 2006
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Deep Survey Optical Fields

• 10 sq. deg. on CFHT
• R 24.5, z 23.5 (AB)
• WFCAM K 21.0 (AB)
• Clusters out to z 1.5
• Feedback on SZ selection function
• Red Cluster Sequence (e.g. Gladders Yee)
• Voronoi tessellation (Culverhouse)
• Full Bayesian analysis (Zwart Hobson)
• Spectroscopy

0.96
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Other Science

• CMB power spectrum at high angular scales (l gt
  3000, cf VSA)
• Other non-Gaussian features, e.g. cosmic strings,
  ionization regions

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Summary

• AMI has started obs of known clusters
  (astro-ph/0509215)
• Shallow blind survey of optical fields begins
  summer 2006
• Deep survey as soon as LA commissioned
• Open to guest observers

19 March 2006
Jonathan Zwart, Cavendish Astrophysics
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