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C.Carilli, AUI Board October 2006. ISAC-run three year process: Quantified ‘experiments’ for future large area cm telescopes 50 chapters, 90 authors, 25% theorists.
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C.Carilli, AUI Board October 2006 • ISAC-run three year process: Quantified ‘experiments’ for future large area cm telescopes • 50 chapters, 90 authors, 25% theorists
Key Science Projects: (i) Address key questions, (ii) Unique role of radio, or complementary but critical, (iii) Excites broad community Cosmic reionization and first light HI + continuum survey: galaxy evolution and dark energy Cosmic magnetism: origin and evolution Strong field tests of GR using pulsars Cradle of Life: Terrestrial planet formation + astrobiology + SETI
KSP I: Cosmic magnetism -- Origin, Structure, Evolution Experiment: All Sky Polarization/Rotation measure survey (σ 0.1 μJy at 1.4GHz) -- 2e7 RMs, spaced by ~ 90" (vs. 1500 currently) Currently: 300 local pulsar RMs SKA: 2e4 pulsars 2. Nearby galaxies Synchrotron+RMs: test dynamo models 3. Distant radio galaxies: Intercluster magnetic fields 4. Ly-a absorbers: galaxian magnetic field evolution over cosmic time 5. Cosmic web: the magnetized intergalactic medium
KSP II: Galaxy evolution and dark energy Experiment: All sky HI line + continuum survey -- 1e9 Galaxies in HI out to z=1.5 1e4/deg^2 in HI to z=0.5 to 1.5 Goal 1: Galaxy evolution – conversion gas to stars
Goal 2:SKA as Dark Energy Machine DE EoS: w = P/ = -1? Func(z)? Baryon Oscillations + Weak lensing: Evolution of LSS -- ‘standard ruler’ SKA: variance limited SKA: measure w(z) to few % w(z) = w0 + w1 z
KSP III: Study of Cosmic reionization and first light The last unexplored phase of cosmic evolution (0.1 to 1Gyr after BB) Experiment: Imaging 3D ‘tomography’ of IGM in HI 21cm line “Richest of all cosmological data sets” 9 7.6 z=12 (109MHz)
SDSS J1148+5251: Observing first light at radio wavelengths J1148 VLA: CO 3-2 at 45GHz z=6.42; t_univ=0.87 Gyr 50K Fan + 1” 1e9 M_sun in dust, 1e10 M_sun in mol. gas => • Hyper luminous IR galaxy (FIR =1e13 L_sun): SFR = 1e3 M_sun/yr ? • Coeval formation of SMBH/galaxy? • Dust formation by massive stars? • Break-down of M- relation at high z? • Early enrichment of heavy elements (z_sf > 8) • Integration times: hours to days on HLIRGs
Complementarity Mol. Gas, dust SKA Stars, ionized gas AGN, star formation Low order mol. lines
KSP IV: Gravity Beyond Einstein Experiment: 2e4 Galactic pulsars Strong field GR tests using pulsar-black hole binaries Pulsar Timing Array: most sensitive gravity wave detector for SMBH binaries
KSP V: Cradle of life • Terrestrial planet formation: disks and gaps on sub-AU scales (complementary with ALMA). • Prebiotic large molecules (abiotic amino acids) • Search for Extraterrestrial Intelligence: leakage radiation (interstellar TV)
All require sensitivity: A/T >= 1e4 m^2/K • Most require frequencies >= 10 GHz • Many require > 1deg^2 FoV at 1.4 GHz • Some require > 1000 km baselines • A few require multibeaming
Pathfinders • Freq (GHz) Year Focus • EVLA I 0.3 – 50 2012 Broad, thermal • eMERLIN 1 – 30 2010 High resolution • ATA 1 – 10 2008? Wide fields • DSN 8, 32 2010? Telemetry • LWA 0.03–0.08 2009 Low freq window • LOFAR 0.08 – 0.3 2009 EoR++ • MWAd 0.1 – 0.3 2009 EoR+ • PAPER 0.1 – 0.2 2008 EoR • SKADS (europe) 0.1 – 25 2015++ HI survey (aperture array) • xNTD (Oz) 0.7 – 1.4 2010 HI survey (FPA) • South Africa 0.7 – 1.4 2010 HI Survey (FPA) • SKA-TDP (USA) 0.3 – 25 2010 Nd
Goal 4: Hubble constant through direct measurement: Water Maser Disks (Greenhill) • Future 1% measures of CMB and related require 1% measure of Ho for fully constrained cosmological parameters: covariance • Water masers disks into the Hubble flow can provide direct measure of Ho to 1% dh
Case for frequencies up to 45 GHz: Thermal objects Rayleigh-Jeans curve implies thermal objects are a factor four stronger (in Jy) at 45GHz relative to 22 GHz => a 10% demonstrator becomes 40% of the SKA 10% demonstrator