Early Science with AMI Jonathan Zwart jtlz 2mrao

Early Science with AMI Jonathan Zwart jtlz 2@mrao. cam. ac. uk

Overview • Case Study: Abell 1914 • Observing strategy & science goals – Early cluster targets – Survey plans 19 March 2006 Jonathan Zwart, Cavendish Astrophysics 2

A 1914: 228 Hours with Ryle 19 March 2006 Jonathan Zwart, Cavendish Astrophysics 3

A 1914: 34 Hours with AMI Long baselines 19 March 2006 Short baselines (after radio sources Jonathan Zwart, Cavendish Astrophysics removed) 4

19 March 2006 Jonathan Zwart, Cavendish Astrophysics 5

• Only 7 (/10) antennas • 18 point sources subtracted Need for source subtraction • astro-ph/0509215 (MNRAS accepted) 19 March 2006 Jonathan Zwart, Cavendish Astrophysics 6

Observing Strategy • • Known clusters Initial blind surveys Surveys of equatorial fields (need LA) Joint fields (AMi. BA, SZA, UKIDSS…) 19 March 2006 Jonathan Zwart, Cavendish Astrophysics 7

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 8

NORAS-Selected Clusters Selection criteria: – LX > 6. 8× 1044 erg s-1 – z > 0. 1 Calibrate scaling relations L–T, M, etc +X-ray g, H 0 A 263: 10 hours; z = 0. 3; (Natasha Hurley-Walker) 19 March 2006 Jonathan Zwart, Cavendish Astrophysics 9

MACS-Selected Clusters Selection criteria: – LX > 1045 erg s-1 – z > 0. 5 Evolution of scaling relations with z +X-ray g (z), H 0, q 0 MACS 0717+37: 8 hours; z = 0. 545 19 March 2006 Jonathan Zwart, Cavendish Astrophysics 10

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 Jonathan Zwart, Cavendish Astrophysics 11

Deep Survey – Optical Fields • ~ 10 sq. deg. on CFHT 0. 96 ° • 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) 19 March 2006 • Voronoi tessellation (Culverhouse) Jonathan Zwart, Cavendish Astrophysics 12

Other Science • CMB power spectrum at high angular scales (ℓ > 3000, cf VSA) • Other non-Gaussian features, e. g. cosmic strings, ionization regions 19 March 2006 Jonathan Zwart, Cavendish Astrophysics 13

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 14