early science with ami
DESCRIPTION
Jonathan Zwart [email protected]. Early Science with AMI. Overview. Case Study: Abell 1914 Observing strategy & science goals Early cluster targets Survey plans. 19 March 2006. Jonathan Zwart, Cavendish Astrophysics. 2. A1914: 228 Hours with Ryle. 19 March 2006. - PowerPoint PPT PresentationTRANSCRIPT
Early Science with AMI
Jonathan [email protected]
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 2
Overview
• Case Study: Abell 1914
• Observing strategy & science goals– Early cluster targets– Survey plans
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 3
A1914: 228 Hours with Ryle
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 4
A1914: 34 Hours with AMI
Long baselines Short baselines
(after radio sources removed)
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 5
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 6
• Only 7 (/10) antennas
• 18 point sources subtracted Need for source subtraction
• astro-ph/0509215 (MNRAS accepted)
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 7
Observing Strategy
• Known clusters
• Initial blind surveys
• Surveys of equatorial fields (need LA)
• Joint fields (AMiBA, SZA, UKIDSS…)
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 8
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 9
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, H0
A263: 10 hours; z = 0.3; (Natasha Hurley-Walker)
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 10
MACS-Selected Clusters
Selection criteria:– LX > 1045 erg s-1
– z > 0.5
Evolution of scaling relations with z
+X-ray g (z), H0, q0
MACS 0717+37: 8 hours; z = 0.545
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 11
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 12
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
°
19 March 2006 Jonathan Zwart, Cavendish Astrophysics 13
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 14
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