July 19 2002 from: carilli to: rawlings re: science case Steve, I was going through the process of looking at the boarder line science, and sort of got carried away. Following is my (complete?) summary of the SKA science programs based on all the meetings etc... over the last few years, plus some of my own thoughts. I point out the things that are now completely missing from any documents, although there are many sub-items that are partially missing as well. cc -------------------------------------------------------------------- SKA Science based on: Bologna, Berkeley, Taylor+Braun, Amsterdam, (and some personal ideas) --------------------------------------------------------------------- July 14, 2002 summary: C. Carilli --------------------------------------------------------------------- WG 4: Galaxy formation (chair: vd Hulst) ---- 1. HI 'Sloan x 100' survey: sensitive, wide field surveys of HI 21cm emission to significant (z >= 1) redshifts. a. Evolution of gas and dark matter content of galaxies b. Evolution of merger rate c. Origin of Hubble sequence and density-morphology relation need: New simulations including evolution of HI mass function. questions: What is optimal resolution, and what fraction of the total collecting area is required? LEVEL 1 2. nanoJy radio sky: sensitive wide field surveys of radio continuum emission to nano-Jy sensitivity a. Dust-unbiased star formation rate density evolution b. Radio Butcher-Oemler effect: star formation in cluster galaxies c. Nature of the mJy submm sources: dust obscured, high z starbursts = forming spheroidal galaxies? d. Evolution of black hole formation and accretion rate: black hole mass -- bulge mass relation and the (possible) coeval formation of massive black holes and spheroidal galaxies. need: Simulations with current best estimates of source population evolution. Sources beyond EOR: will radio continuum or SNe or GRB radio emission be detectable? Will any show up (by chance) in deep surveys? questions: What resolution is optimal to separate star forming galaxies from AGN, but without losing too many of the extended sources due to over-resolution? What is the (sidelobe) confusion limit for given configurations? LEVEL 1 3. High redshift molecules: searches for very high redshift thermal and non-thermal molecular line emission from early galaxies. a. Dense molecular gas: low order CO, HCN, ... sensitivity, wide FoV, large fractional bandwidth allow for very large volume searches. b. Probing beyond the EOR: earliest star forming galaxies c. OH megamasers: sign-posts to high z star forming galaxies needed: Refined simulations considering galaxy properties beyond EOR. Calculations of HCN emission: is HCN/CO a discriminator between AGN and Starburst? LEVEL 1 or 2? 4. Radio absorption lines: studies of HI and molecular absorption toward high z, mJy radio sources. a. dust-unbiased census of high column absorption line systems by gas associated with high z galaxies b. detailed study of dense, pre-star forming ISM in early galaxies: kinematics, astrochemistry, physical conditions c. evolution of physical constants: FSC, other? needed: Revised calculations of number of absorption systems and number of continuum sources expected for a given deep HI survey (include in grand simulation?) questions: HI emission vs. absorption sensitivity: can we derive HI spin temperatures? LEVEL 2 5. Low z cosmic web: residues of galaxy formation a. sensitive imaging of extended HI around galaxies, and/or HII free-free emission: ionization edges of galaxies and the intergalactic radiation field. b. Faint end of HI mass function: nature of HVCs c. Studying the missing dwarf problem. d. Galaxies in cosmic voids e. LSB galaxies: HI and dark matter properties f. Low z Lyman alpha forest: relationship to galaxies? g. Diffuse radio continuum emission around galaxies: galaxy outflows and pollution of the IGM h. Dark matter: extending rotation curves radially and vertically, and HI studies of tidal interactions and galaxy groups: Extent, distribution, and nature of dark matter in galaxies, tests of MOND? needed: Include LSB, new HI mass function results. Calculations of low z ly alpha forest: can we probe to extremely low columns in absorption again very bright sources (1e16? 1e15?) questions: should this be in nearby galaxy panel? LEVEL 1 --------------------------------------------------------------------- WG ?: Life cycle of stars (chair: Dougherty) ---- 1. Protoplanetary disks and planets: planet formation in dusty disks a. sub-AU imaging of disk gaps, planet migration (10 K at mas res plus probe deeper into disk due to dust opacity). needed: detailed calculations (simulation?) of SKA capabilities questions: optimal UV coverage and frequency for these studies? LEVEL 1 2. Radio properties of normal stars: physics of stellar atmospheres and the solar-stellar connection a. imaging stellar photospheres b. Radio HR diagram: detecting thermal emission from cool stars to 50 pc c. flares (solar-type and active stars): magnetic activity cycles, stellar dynamos, rotational modulation d. nonthermal coronal activity in MS stars and VLBI imaging of coronal structure LEVEL 1 3. mas astrometry, imaging: a. parallax to 1 kpc b. binary orbits c. optical-radio reference frame: tie to mas scale over full sky d. angular expansion of planetary nebulae and stellar winds e. maser proper motions: Galactic and extragalactic question: can SKA detect planets through stellar proper motion studies or other (sub-mas astrometry)? LEVEL 2 4. Protostars and dense protostellar cores: origin of IMF, fraction of molecular cloud converted into stars a. high resolution imaging of magnetic fields using molecular Zeeman obs b. subAU imaging of jets: jet origin and collimation and temporal behavior (proper motions) c. circumstellar envelopes: masers, thermal emission d. dynamic imaging of ammonia/other molecules on subAU scales: uncovering the evolutionary sequence (dense core to protostar) e. non-thermal emission: jets f. prebiotic chemistry needed: detailed calculations: what will SKA do in these areas? questions: Required polarization purity for Zeeman? Required UV coverage for high resolution continuum imaging, and optimum frequency? Required UV coverage for molecular line studies? LEVEL 1 -------------------------------------------------------------------------- WG ?: Cosmology and Large Scale Structure (chair: Briggs) ---- 1. Studying the epoch of reionization a. Imaging HI 21cm emission from LSS (or statistical clustering of SSS) during the EOR. b. Searching for HI 21cm absorption prior to the EOR i. The HI 21cm forest: absorption by the filamentary neutral IGM ii. Minihalos and proto-disks: absorption by collapsed structures needed: synthesize current simulations questions: Configuration requirements: absorption requires arcsec resolution, emission requires arcmin. LEVEL 1 2. Large scale structure: a. HI surveys i. evolution of clustering of gas rich galaxies ii. Peculiar motions using tully-fisher distances: determining the bias parameter iii. high z cluster vel dispersions b. CMB: i. polarization of CMB ii. small scale structure in CMB c. IGM: i. Relativistic component of IGM (electrons, mag fields) ii. Diffuse (relativistic) gas between clusters: fate of free energy of universe iii. cluster evolution through observations of cluster halos iv. SZ imaging: finding high z clusters, high res imaging d. weak lensing: cosmic shear needed: more details on CMB/SZ studies with SKA questions: is SKA a player in the weak lensing game? LEVEL 1 3. Cosmological parameters a. determining H_o with strong lensing b. determine Omega from number of lensed sources c. determining distance scale with water masers disks d. Thompson scattering halos: an SZ analog e. A-P test: ?? needed: more details in all areas LEVEL 1 ------------------------------------------------------------------------- WG?: Supermassive black holes and the AGN environment (chair: Falcke) ---- 1. Relativistic jet and accretion disk physics: a. Jet formation and the state of the accretion disk: probing sub-pc scales b. physics of pc-scale accretion disks i. water maser disks: most direct evidence for SMBH ii. imaging thermal emission from disks on sub-pc scales iii. A/B/C-DAFs: testing the weakly radiating accretion disk paradigms iv. HI, free-free absorption: gas distribution, dynamics c. physics of kpc-scale environments i. high resolution continuum imaging: co-eval starbursts? ii. molecular gas distribution in high z sources d. Physics of kpc-scale jets and their interaction with the ICM i. physics of relativistic flows: fields, pressures, velocities, confinement, etc... ii. interaction with ICM: cluster bubbles and shells, heating of the ICM, pollution of ICM by jets LEVEL 1 2. Evolution of radio galaxy populations: a. Evolution of luminosity function: FRI, FRII b. Origin of FRI-FRII dicotomy c. Origin of radio loud - quiet dicotomy d. testing theories of unification by orientation question: Is SKA really needed for this? LEVEL 2 3. The Galactic center: the nearest supermassive black hole a. Testing AGN models with ultra-high resolution imaging of Gal Center a. General relativistic shadow (also in other nearby AGN?) b. gas dynamics, star formation, magnetic fields, etc... needed: Missing from science case LEVEL 2 ---------------------------------------------------------------------- WG ?: Transients, stellar end products, SETI (chair: lazio) 1. Survey of variable radio sky LEVEL 1 2. Pulsars: a. complete census of pulsars in the Milky Way: i. more ms pulsars for GR tests ii. Timing array: gravitational wave detector iii. tomographic map of ionized gas distribution b. Extragalactic timing to 1 Mpc, giant pulses to 5 Mpc c. 'mapping' pulsar emission regions by studying pulse profiles LEVEL 1 3. Supernovae and supernova remnants a. Searches for young SNRs/Old SNe (30 to 100 years) b. high z supernovae: radio light curves as distance indicators? c. imaging SNR expansion: CR acceleration and dynamical effect on ISM LEVEL 2 4. Ultra-high energy CRs: radio emission from air showers or lunar regolith LEVEL 2 5. SETI: interstellar TV LEVEL 2 6. Microquasars and Exotic stars (Xray transients): Galactic and extragalactic a. AU resolution imaging: jet formation around solar mass black holes and connection to accretion disk processes. b. high time resolution timing: correlation with accretion disk physics needed: Missing from science case questions: should this be under stellar WG or Galactic? LEVEL 1 7. GRBs: going fainter and further a. testing fireball models: detecting GRBs early in light curve (min to hours) b. detecting faint radio emission from GRB host galaxies: starburst connection c. detecting GRBs beyond EOR: HI 21cm absorption probes? needed: more details on SKA capabilities for GRB science Missing from science case LEVEL 1 -------------------------------------------------------------------- WG ?: Galactic and nearby galaxies (chair: Dickey) ---- 1. Galactic atlas: global 3D distribution and interaction of different phases of the ISM: molecular, CNM, WNM, WIM, HIM, relativistic a. mapping the dynamic ISM: chimneys, shells, Mag stream b. relationship between star formation and ISM needed: detailed calculations of SKA capabilities in these areas. Calculations of SKA observations of RRL. LEVEL 1 2. Galaxian magnetic fields a. disk and halo: morphology and strength b. testing dynamo theories question: Required wide field polarization DNR? LEVEL 1 3. Turbulence in the ISM through scattering measurements a. driving sources b. dissipation scale and energy density LEVEL 2 4. ISM in nearby galaxies: same as 1, with lower physical resolution, but less ambiguous lines of sight a. global gas dissipation processes: bars, density waves, tidal forces b. affect of star formation on ISM LEVEL 1 5. proper motions of local group galaxies through maser studies needed: Missing from science case LEVEL 2 6. Active star forming galaxies: high resolution radio continuum, HI abs/em, FF abs/em, RRLs, and molecular line em. a. Extragalactic radio supernovae: Calibrating star formation rates and the radio-FIR relation b. Nature of star formation in nuclear starbursts: seeing through the dust i. ISM in extreme environments ii. IMF in extreme environments iii. relation to high z, dust obscured star forming galaxies: forming spheroids? iv. super star clusters: forming GCs? c. starburst driven winds and pollution of IGM d. triggering mechanisms for star formation: SSPSF? Bars, density waves? needed: Missing from science case LEVEL 1 -------------------------------------------------------------------- WG ?: DSN, astrometry, geodesy (chair: Jones) ---- 1. Large bandwidth telemetry: movies from mars needed: More detailed science case LEVEL 1 2. Angular navigation of spacecraft: much better orbits to avoid losing ships needed: more details on how much better SKA will do. question: is 24 hr visibility required? LEVEL 1 3. Geodesy and astrometry needed: Missing from science case LEVEL 2 -------------------------------------------------------------------- WG ?: Solar system science (chair: Redman?) ---- 1. Studying the sun a.Coronal mass ejections: using low frequency radar, determine the 3D dynamics of CMEs as critical early-warning system for satellites and other sensitive terrestrial structures. b. interplanetary scattering: 'imaging' the solar wind LEVEL 1 2. Imaging thermal emission, and radar imaging, of solar system objects a. asteriods = protoplanets 'frozen' in different states of early evolution. study geological history, prospect for minerals, and probe beneath the regolith. Radar provides most accurate orbits (by far), particular interesting for near earth objects, and sub-km-scale imaging. b. Planetary satellites: at 20km resolution study cool lava flows on Io, ice tectonics and water volcanism, and other surface structure on large planet satellites. c. Kuiper belt objects: best example of physical properties of large objects in protoplanetry dust disks ('proplids'). Almost nothing currently known (shapes, masses, rotation). d. Comets: imaging gas around comets (OH, other). Get a 3D image of cometary outflow structures, including jets and large fragments. e. Mars, Venus, Mercury? needed: more details on planet studies LEVEL 1 3. Imaging nonthermal emission from giant planets: constrain electron spectrum and mag field distribution LEVEL 2 --------------------------------------------------------------------