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Evolution of radio telescopes (Braun 1996)

Evolution of radio telescopes (Braun 1996). SKA in context. Fields of View. Centimeter observations of thermal sources at mas resolution. X PP-disks. X NGC1068 Disk. ISAC Mandates:

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Evolution of radio telescopes (Braun 1996)

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  1. Evolution of radio telescopes (Braun 1996)

  2. SKA in context

  3. Fields of View

  4. Centimeter observations of thermal sources at mas resolution X PP-disks X NGC1068 Disk

  5. ISAC Mandates: • Revise science case and requirements, involving larger community, and put in context of future capabilities at other wavelengths. Goal: new Taylor-Braun document by Aug. 2004. • Evaluate (w. EMT) proposed SKA designs and advise ISSC. Goal: final design and site choice by ISSC in 2007 • Current documentation: • Science with the Square Kilometer Array, R. Taylor & R. Braun, 1999 (www.skatelescope.org/ska_science.shtml) • Perspectives on Radio Astronomy: Science with Large Antenna Arrays, ed. M. van Haarlem, 1999 (ASTRON) • SKA memo series: Groningen (2002), Bologna (2002), and Berkeley(2001), science working group reports (www.skatelescope.org/ska_memos.shtml)

  6. SKA Designs ("compliance" matrix) http://www-astro.physics.ox.ac.uk/~sr/ska/ska_matrix.html Compliance Matrix: www-astro.physics.ox.ac.uk/~sr/ska/ska_matrix.html Notes: Level-1 science may still be missing. 'Level-1' probably not a uniform measure across the WGs. Last updated: 10th August 2002

  7. Highest z HI emission to date: 110 hours VLA + GMRT Verheijen, Dwarakanath, van Gorkom

  8. Maximum redshift for a 360 hour integration with SKA 2000 galaxies/ deg M 101 100 000 Star formation with z 30 000 M 51 SMC Crucial epoch

  9. z = 4 z = 2

  10. Braun 1996 M101 z = 0.2 Imaging to z=1 => TF distances => peculiar motions z = 0.45 z = 0.9

  11. SKA HI Survey: ‘Sloan x 100’ 1000 hrs, 1000 sq.deg. Evolution of gas and dark matter content of galaxies Origin of Hubble sequence and density-morphology relation Evolution of LSS and cluster velocity dispersions Tully-Fisher distances: Peculiar motions => evolution of bias parameter

  12. SKA continuum survey: HDFx10000 Hopkins 1999 5e8 sources at > 0.3 uJy over 1000 sq.deg. Star formation history of the universe unbiased by dust Massive black hole formation and accretion history

  13. Dust obscured star formation at high z: The brightest mm source in HDF not detected by HST! Elliptical galaxy formation in dusty, high z starbursts?

  14. Maximum redshift for a 360 hour integration with SKA resolved flux (0.1”) total flux (1”) M 51 resolved flux total flux NGC 6946 Thermal flux M 33

  15. HI 21cm absorption in deep, wide surveys 1229-021 Briggs 1996 z_abs = 0.4 N(S>1mJy) = 36000 => O(50000) HI 21cm absorption lines by damped Ly alpha systems (1e20 /cm/cm, T_spin = 1000 K) Dense ISM in nascent galaxies Dust unbiased QSO statistics: ‘Red quasars’ and ‘dark’ gravitational lenses Evolution of physical constants

  16. OH megamasers in deep HI surveys: beacons to high z, merging starburst galaxies Briggs 1995

  17. Highest z CO emission to date: 24 hrs/source w. VLA M(H_2) = few e11 M_sun 1202-0725 z =4.69 CO(2-1) 1331-0417 z = 4.41 CO(2-1) 0827+5255 z = 3.91 CO(1-0) 2322+1944 z = 4.12 CO(2-1)

  18. 0827+5255 at z=3.9: An ‘Einstein Arc’ in CO CO(2-1) 8 GHz 300 pc HST

  19. SKA and CO M(H_2) = few e9 M_sun 22 GHz 43 GHz

  20. Optimal CO surveys: ‘speed of discovery’ Carilli and Blain 2002

  21. HCN (89 GHz): Dense gas + starburst tracer? Solomon 2001

  22. Conflict I: low vs. high frequency? HI Surveys require frequencies < 1.4 GHz CO Surveys require frequencies > 20 GHz Can we do both with one design?

  23. Epoch of Reionization:

  24. Evolution of the neutral IGM (Gnedin): ‘Cosmic Phase transition’ HI fraction Ionizing intensity density Gas Temp

  25. Gunn-Peterson effect Barkana and Loeb 2001

  26. Discovery of the EOR?(Becker et al. 2002) Fast reionization at z= 6.3 => opaque at l_obs < 1 mm

  27. Lower limit to z_reio: GP Effect Fan et al. 2002 F(HI) > 0.01 at z = 6.3

  28. Upper limit to z_reio: CMB anisotropies Briggs

  29. Studying the IGM beyond the EOR: HI 21cm observations with the Square Kilometer Array and LOFAR t_21cm = 1e-8 t_Lya

  30. Temperatures: Spin, CMB, Kinetic and the 21cm signal Tozzi 2002 T_s T_CMB T_K • Initially T_S= T_CMB • T_S couples to T_K via Lya scattering • T_K = 0.026 (1+z)^2 (wo. heating) • T_CMB = 2.73 (1+z) • T_S = T_CMB => no signal • T_S = T_K < T_CMB => Absorption against CMB • T_S > T_CMB => Emission

  31. HI 21cm Emission

  32. Difficulty with (LSS) emission observations: confusion by foreground radio sources (di Matteo 2001)

  33. Cosmic Webafter reionization = Ly alpha forest (d <= 10) 1422+23 z=3.62 Womble 1996 N(HI) = 1e13 -- 1e15 cm^-2, f(HI/HII) = 1e-5 -- 1e-6 => Before reionization N(HI) =1e18 – 1e21 cm^-2

  34. Cosmic Web before reionization: HI 21cm Forest Carilli, Gnedin, Owen 2002 • Mean optical depth (z = 10) = 1% = ‘Radio Gunn-Peterson effect’ • Narrow lines (1 to 10%, few km/s) = HI 21cm forest (d = 10)

  35. SKA observations of absorption before the EOR A/T = 2000 m^2/K 240 hrs 1 kHz/channel z = 10 z = 8

  36. Radio sources beyond the EOR? 0924-220 z = 5.19 S_151 = 600 mJy 0913+5821 z = 5.12 S_151 = 150 mJy 1”

  37. Inverse Compton losses off the CMB = U_B (radio lobe)

  38. Radio sources beyond the EOR: sifting problem (1/1400 per 20 sq.deg.) USS samples (de Breuck et al.) 1.4e5 at z > 6 2240 at z > 6

  39. Conflict II: Long vs. Short baselines? EOR emission requires arcmin resolution => baselines < 5km EOR absorption requires arcsec resolution => baselines > 300km Both are sensitivity limited: where to put our collecting area?

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