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

Current documentation: 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)

Compliance Matrix: www-astro.physics.ox.ac.uk/~sr/ska/ska_matrix.html 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 Level 1 Science Strawman  China  Europe  India  Ozlens  Ozcyli  USA  Canada  1: Galactic HI YES UPGRADE? 1: Galactic NT+B NO 2: Transients 2: Pulsars 2: SETI 3: EOR 4: HI surveys / LSS 4: Continuum surveys 4: CO surveys 5: Hi-z AGN 5: Inner AGN 6: Protoplanetary systems 7: CMEs 7: SS bodies 8: IGM non thermal 8: IGM thermal 9: Spacecraft Tracking 9: Geodesy Notes: Level-1 science may still be missing. 'Level-1' probably not a uniform measure across the WGs. Last updated: 10th August 2002

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

M 101 M 51 SMC Maximum redshift for a 360 hour integration with SKA 2000 galaxies/ deg M 101 100 000 Star formation with z 30 000 M 51 Out to where do we detect what mass galaxies in a 360 hour deep field HI survey. Slide illustrates mass ranges of dwarf, normal (L*) and giant galaxies. SMC Crucial epoch

z = 4 z = 2

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

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

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

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?

Maximum redshift for a 360 hour integration with SKA resolved flux (0.1”) total flux (1”) M 51 resolved flux total flux NGC 6946 Continuum of normal galaxies: to what redshifts de we detect normal galaxies in a 360 hour integration and a 500 MHz bandwidth piggy-back survey with the HI deep fields Thermal flux M 33

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

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

Highest z CO emission to date: 24 hrs/source w 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)

0827+5255 at z=3.9: An ‘Einstein Arc’ in CO 8 GHz 300 pc HST

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

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

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

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?

Epoch of Reionization:

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

Gunn-Peterson effect Barkana and Loeb 2001

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

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

Upper limit to z_reio: CMB anisotropies Briggs

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

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

HI 21cm Emission

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

Cosmic Web after 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

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)

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

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

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

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

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?