Wallaby and SKA HI surveys. Lister Staveley-Smith

Transcription

1 Wallaby and SKA HI surveys Lister Staveley-Smith

2 Outline HI surveys with SKA pathfinders Wallaby/HI science Wallaby design study simulations techniques SKA phase 1 science coordination

3 Outline HI surveys with SKA pathfinders Wallaby/HI science Wallaby design study simulations techniques SKA phase 1 science coordination

4 LMC. Stars & ionised gas (Smith; CTIO) HI (Kim et al., Staveley- Smith et al.; ATCA/PKS)

5 . LMC/SMC optical (Mellinger) LMC/SMC HI Parkes (Bruens)

6 Dark and tidal galaxies Dark galaxy VirgoHI21 detected in HIJASS observations (Davies et al. 2004). Minchin et al. (2005) claim lack of stars (inc.hst) and high rotation velocity suggestive of true dark galaxy. Other observations (Kent et al. 2007) and models (Bekki et al. 2005; Duc & Bournaud 2008) suggestive of tidal interaction. ALFALFA Virgo results (Kent et al.) Duc & Bournaud (2008)

7 Simulations Cold gas (blue) flowing into a galaxy at z=3 (Agertz, Teyssier & Moore 2009)

8 Wallaby (WIDEBAND ASKAP L-BAND LEGACY ALL-SKY BLIND SURVEY)

9 Wallaby: summary A-rated ASKAP Survey Science Proposal Design study phase Angular resolution: 30 arcsec Area: 3π Bandwidth: 300 MHz (z=0 to 0.26) Frequency resolution: 18.3 khz (4 km s -1 ) RMS flux density (0.1 MHz): 0.7 mjy/beam RMS column density sensitivity (0.1 MHz): 1.7x10 19 cm -2 Cube volume: 330 TB (uv data 50 PB)

10 ASKAP01 Dave De Boer/CSIRO

11 Wallaby: Simulated sky and redshift distribution (Beutler) 500,000 galaxies

12 The Local Volume HI Survey (LVHIS) B. Koribalski, A. Lopez-Sanchez, E. Kirby, E. van Eymeren, L. Staveley-Smith, E. de Blok, J. Ott, N. Bonne, Jerjen

13 Science aims Local Group MW halo low-mass galaxies Galaxy properties in different environments HI mass function Understanding star formation Cosmology SkyMapper Tully-Fisher/SN1A dark matter map Baryon oscillations at z=0

14 Leo T: a transitional dwarf galaxy in the Local Group Irwin et al. 2007; Ryan-Weber et al GMRT 30 resolution (same as WALLABY)

15 Local Group velocity function: the missing satellite problem (Simon & Geha 2007) Keck spectroscopy of 8 new SDSS Milky Way satellites

16 Outline HI surveys with SKA pathfinders Wallaby/HI science Wallaby design study simulations techniques HI survey wedding cake SKA phase 1 science coordination

17 Simulated HI skies (Zwaan) Wallaby Dingo 30,000 deg 2 30deg 2

18 Wallaby simulation: confusion not a problem; non-uniform noise might be. 30 deg 2 32 (ideal) beams 30 antennas 2 km baseline 8 hrs 92.5 khz (20 km s -1 ) SKADS-SAX input catalogue (Obreschkow et al.) ASKAP computing group

19 Cosmic Web predictions Duffy, Schaye et al. (OWLS collaboration) 14 log Σ HI (cm -2 ) log Σ H (cm -2 ) H 0 H + 50 h -1 Mpc See also Popping et al. (2009); Crain et al.; GIMIC

20 OWLS simulation of baryonic Tully-Fisher relation at z=0 & 2 (Scrimgeour & Duffy) z = 0 z = 2 Total M bar [M ] BTF slope shallower at higher z Feedback: AGN, SNI, SNII Stellar evolution Radiative cooling/heating V max [km/s]

21 Outline HI surveys with SKA pathfinders Wallaby/HI science Wallaby design study simulations techniques SKA phase 1 science coordination

22 Stacking n-dimensional images Shift e.g. using a catalogued source position Stretch e.g. to account for psf or cosmology Summation or other statistic

23 121 galaxy GMRT stack: galaxies at z=0.24 Lah et al. (2007)

24

25 Deep HI integrations by stacking Delhaize Observe region with optical redshift coverage Shift-and-add (stack) HI spectra systematics confusion noise

26 A stacked HI signal at z=0.1 with Parkes (GAMA9 field; Delhaize et al.) randomized catalogue

27 Evolution of Ω(HI) Freudling, Staveley-Smith 10

28 Outline HI surveys with SKA pathfinders Wallaby/HI science Wallaby design study simulations techniques SKA phase 1 science coordination

29 SKA Phase 1 definition Science case (Carilli & Rawlings 2004) science justification Design Reference Mission (SWG 2009) science requirements Science prioritization (SPDO) key projects ( sharpening the SKA science case )

30 Pathfinder HI Survey Coordination Committee (PHISCC) Role Discuss HI pathfinder surveys on ASKAP/MeerKAT/WSRT- Apertif key projects and coordination Current Membership ICRAR, CASS UCT Astron Simulation (Oxford) SPDO and US observers Meetings Groningen (June 2009) Bunker Bay (Oct 2010) Arniston (May 2010)

31 Blind HI survey wedding cake All-Sky (40,000 deg 2 ) Wallaby (ASKAP) + Apertif (WSRT) + FAST 500,000 galaxies out to z=0.26 Medium Deep ( deg 2 ) SDSS (Apertif) Deep ( deg 2 ) Dingo (ASKAP) 100,000 galaxies out to z= deg 2 (GAMA/GAMA2 regions) Ultra-deep (2-30 deg 2 ) ASKAP Dingo (30 deg 2 out to z=0.4) Asseghai/MeerKAT (4 deg 2 out to z=1.4) [evla (clusters at z<0.4)] Apertif MeerKAT

32 Summary Wallaby design study in progress: science simulations (hydro, semi-analytic) telescope simulations (ASKAP computing group; WSRT) deep HI studies (AUDS, stacking); also GMRT, WSRT soon: source-finding & parameterisation (CASS; ICRAR) detailed survey design BETA commissioning SKA phase 1 definition input from Wallaby science and simulations; PHISCC

33

34 Parkes

35 ASKAP

36 ASKAP