1. Cosmology using 21 cm emission Jeff Peterson, CMU Talk 1…Update on early ionization telescopes (LOFAR, PAST, GMRT) Talk 2…Proposed Redshift survey

2. Telescopes with > 10,000 m^2 area that will be used in attempt to detect early (z~10) ionization LOFAR PAST/21CMA GMRT

4. Simulated VHF sky images Furlanetto, et.al2003

5. Extragalactic Foregrounds

6. NETHERLANDS: LOFAR 120-240 MHz ~10,000 dipoles Blue Gene correlator Extensive outrigger network 53 M euros Operational 2007

7. TEST ARRAYS “ITS”

9. CHINA:The Primeval StructureTelescope, aka 21 CM Array

10. E W SN 21CMA Layout

11. Telescope Parameters Rough Parameters Total antennae 10,000 Interferometer Elem. 81 Effective area 20,000 m^2 Sky temperature 200 K – 2000 K Imaging field of view 100 sq deg Angular resolution 5 arc minutes Frequency Range 70 - 200 MHz Redshift range 6 - 20 Frequency resolution 20 kHz Spatial resolution 6 Mpc Mapping sensitivity 25 mK/sqrt(day) Budget $3M Operational 2006 280 antennae, on site, Ulastai June 2004 Over 2000 Installed, December 2004

13. INDIA: The Giant Metrewave Radio Telescope 30 44 m dishes Currently hobbled by power line noise New PC based correlator summer 2006 Budget $200,000 plus exisitng GMRT

14. Questions on Early Ionization

15. 21 cm redshift survey to constrain dark energy By Jeff Peterson and Ue-Li Pen Use acoustic oscillations from z = 0 to z = 1.5 to detail the transition from deceleration to acceleration. Survey 2 Pi steradians from 500 to 1500 MHZ with a 250,000 sq m fixed-pointed meridian- scan radio telescope. Cylindrical reflectors allow for ultra-wide field observations, and inexpensive FFT based beam forming. Modest cost--$20M--$0.02/redshift

16. Baryon Wiggles Detected by SDSS and 2df

17. Projected W and W’ sensitivity Blake and Glazebrook

18. Dark Energy Constraint vs. redshift limit

19. Local HI Luminosity Function Zwann et al at z=1.5 this is 2 microjansky We detect all these across 1/2 of sky in 6 months

20. Four Cylinders each 2 km long Line feeds at foci used to create 4000 beams N 2 km

21. Cylindrical reflectors use suspended mesh, with a line of feed points Reflector Cost: ~$20/m^2 Survey Speed~A*N

22. Existing cylinders MOLONGLO Cost:$12/m^2 (current dollars) OOTY Both rotate in one dimension Molonglo AUSTRALIA Brisbane Darwin Perth Canberra Hobart Adelaide Melbourne Sydney +

23. Cylinder History Popular 1960-1980 Lost favor with advent of cryogenically cooled pre-amplifiers. Room temp amplifiers with 20K noise temp now available. Illinois 400 ft Telescope ca. 1960

24. Beam Former Signal Flow FFT vs t Transpose FFT vs t 4096 ADCs … FFT vs x

25. 64 x 64 Processor Array 64 One of 4096 RF signals

26. Conclusions Using off the shelf technology, a redshift survey telescope can be built for modest cost ($20M) which will yield 10^9 redshifts to z~1.5 Will cover 100 times the SDSS volume Will constrain W1 to ~0.1

27. Subaru Deep Field z~6 Ly alpha