A P E RT I F HI imaging surveys Marc Verheijen! + Apertif team Periphery of Disks, Sydney, 3-6 Nov 2014 a grand proposal WSRT upgrade - SKA pathfinder After 45 years of service,! transform the WSRT into! an efficient 21cm survey facility! using phased-array technology. Winning community support + 3 NWO/NOVA investment grants + 3 ERC grants: ‣ HIstoryNU - van der Hulst, 2.5 M€! ‣ RadioLife - Morganti, 2.5 M€! ‣ ALERT - van Leeuwen, 2 M€ 2006 5 M€ 2008 2.5 M€ 2013 1.3 M€ Periphery of Disks, Sydney, 3-6 Nov 2014 Major HI imaging surveys Targeted imaging surveys of selected samples:! • WHISP (350) • VIVA (53) • UMa (85) • THINGS (34) • LittleTHINGS (42) • FIGGS (47) • ATLAS3D (166) • HALOGAS (22) • VLA-ANGST (36) northern spirals with F>100 mJy! SFR-selected Virgo spirals! Ursa Major group with MB<−18.5! HI follow-up of SINGS sample! Local dIm and BCDs! Faint Irregular galaxies! HI follow-up of northern early-types! the deepest HI survey of spirals! HI follow-up of HST/ACS survey Blind imaging surveys of different environments:! • Coma (WSRT)! • Perseus-Pisces (VLA-C)! • Ursa Major (VLA-D)! • CVn (WSRT) • ZoA - 3C129 (WSRT) ! • Abell 963 / 2192 (WSRT)! • Cosmos field (VLA-B) Periphery of Disks, Sydney, 3-6 Nov 2014 Galaxy structure and kinematics What causes excessive streaming motions? R. Jay GaBany Shang+ 98 Battaglia et al 2005 Verheijen Boomsma et al Is there a correlation between warps and stellar streams? Do rotation curve shapes depend on galaxy environment? Periphery of Disks, Sydney, 3-6 Nov 2014 How do galaxies acquire their gas? Woerden+ van van Woerden+ 20042004 sustaining sustainingstar starformation formation! sustaining star -formation -! - stellar mass building up building up stellar mass! building up stellar mass ! Evidencefor forcold cold accretion! accretion Evidence Evidence for cold accretion or and/or! or Galactic Fountain /fallback Fallback?? Galactic fountain/ Galactic Fountain / Fallback? M 101 Thilker+2004 2004 Thilker+ M 101 Oosterloo+2007 2007 Oosterloo+ Periphery of Disks, Sydney, 3-6 Nov 2014 How do galaxies acquire their gas? (schaye et al 2010) Woerden+ van van Woerden+ 20042004 OWLS simulations sustaining sustainingstar starformation formation! sustaining star -formation -! - stellar mass building up building up stellar mass! building up stellar mass ! Evidencefor forcold cold accretion! accretion Evidence Evidence for cold accretion or and/or! or Galactic Fountain /fallback Fallback?? Galactic fountain/ Galactic Fountain / Fallback? M 101 Thilker+2004 2004 Thilker+ M 101 Oosterloo+2007 2007 Oosterloo+ Periphery of Disks, Sydney, 3-6 Nov 2014 How do galaxies process their gas? Beards and thick disks : Galactic Fountain & Extraplanar Gas main disk extra-planar gas • • • 10% of HI mass! 20-50 km/s lag! 10-20 km/s inflow Galactic Fountain Fraternali+ (2001) Periphery of Disks, Sydney, 3-6 Nov 2014 How do galaxies loose their gas? NGC 4388 Oosterloo & van Gorkom, 2005 Kenney+ 2004 NGC 4522 ram-pressure stripping in action Periphery of Disks, Sydney, 3-6 Nov 2014 Gas as tracer of formation history Atlas3D : HI imaging of 166 early-types (1/3 HI detected) Lower density regions: extended & regular HI disks Higher density regions: clumpy & unstructured Serra+ 2011 Periphery of Disks, Sydney, 3-6 Nov 2014 The promise of Apertif Chiles Alfalfa HIPASS Periphery of Disks, Sydney, 3-6 Nov 2014 The promise of Apertif 105 HI detections , 104 resolved HI disks Chiles APERTIF Alfalfa HIPASS Periphery of Disks, Sydney, 3-6 Nov 2014 HI mass limits & detection rates 1x12hr : M*HI at z=0.08, 1x1011 Msun at z=0.25! 12x12hr : M*HI at z=0.16, 3x1010 Msun at z=0.25 Periphery of Disks, Sydney, 3-6 Nov 2014 HI column density limits 5σ, W=25 km/s Note: smoothing to half the angular resolution reduces! the survey volume at a particular linear resolution! by a factor 8 . Periphery of Disks, Sydney, 3-6 Nov 2014 It’s all about column density sensitivity Accretion, depletion and removal of gas tidal stripping ram-pressure stripping Oosterloo et al Fraternali et al extra-planar gas Verheijen et al 2x1019 (atoms/cm2) 5x1019 (atoms/cm2) 10x1019 (atoms/cm2) Periphery of Disks, Sydney, 3-6 Nov 2014 A blind HI imaging survey of Perseus-Pisces VLA-C mosaic! 44 pointings! 117 channels! ! 1395-1408 MHz! Θ = 15”! ΔV ≈ 20 km/s! σ = 0.8 mJy/bm! ! MHI, min = 5x108 Msun PhD project: Eva Busekool Periphery of Disks, Sydney, 3-6 Nov 2014 A blind HI imaging survey of Perseus-Pisces VLA-C mosaic! 44 pointings! 117 channels! ! 1395-1408 MHz! Θ = 15”! ΔV ≈ 20 km/s! σ = 0.8 mJy/bm! ! MHI, min = 5x108 Msun PhD project: Eva Busekool Periphery of Disks, Sydney, 3-6 Nov 2014 A blind HI imaging survey of ! Perseus-Pisces in the Zone-of-Avoidance WSRT mosaic! 35 pointings, 1x12hr! 1717 channels! ! 1346-1409 MHz! Θ = 16”x23”! ΔV ≈ 16 km/s! σ = 0.34 mJy/bm includes 3C129! ! 200+ HI detections PhD project: Mpati Ramatsoku Periphery of Disks, Sydney, 3-6 Nov 2014 A blind HI imaging survey of ! Perseus-Pisces in the Zone-of-Avoidance WSRT mosaic! 35 pointings, 1x12hr! 1717 channels! ! 1346-1409 MHz! Θ = 16”x23”! ΔV ≈ 16 km/s! σ = 0.34 mJy/bm includes 3C129! ! 200+ HI detections PhD project: Mpati Ramatsoku Periphery of Disks, Sydney, 3-6 Nov 2014 Detecting & characterizing 3D structures Visualization by! Davide Punzo! Kapteyn Institute Periphery of Disks, Sydney, 3-6 Nov 2014 suggested APERTIF surveys Call for Expressions-of-Interest :! ( 18 EoI’s for >20 years of observing time ) ‣ ‣ ‣ ‣ ‣ ‣ ‣ ‣ ‣ ‣ ‣ low-mass end of the HIMF at <106 M⦿! the neutral ISM and resolved SF! gas accretion and minor merger rates! environmental effects on gas in galaxies! extra-planar gas, warps, streaming motions! ΩHI at z=0.2! HI absorption studies, AGN in/outflows! faint continuum sources (LOFAR)! magnetic fields in external galaxies! radio halos, magnetic fields in galaxy clusters! the variable radio sky (in concert with Palomar Transient Factory) Periphery of Disks, Sydney, 3-6 Nov 2014 drafting APERTIF straw man surveys Guiding principles: ‣ public, legacy-type surveys ! based on input from the community! ‣ collaborate, compromise, consolidate! ‣ be ambitious yet realistic! ‣ simplicity ! few observing modes, fixed pointing grid! ‣ staged delivery of data and science! ‣ maximum ancillary data availability! ‣ community involvement & commitment APERTIF CDR, Dwingeloo, 8-10 Oct 2014 consolidated straw man surveys ‣ ‣ ‣ ‣ ‣ shallow ‘π-of-sky’ survey! medium-deep, wide-area survey! pulsar search survey! Galactic plane survey! commensal transients survey Ball-park time estimate: 5-year survey period (2016−2020)! 25% DDT (VLBI, pulsar timing, ToO)! 75% observing efficiency! ¼ of time dedicated to each survey! → 6200hr ≈ 500x12hr per survey Periphery of Disks, Sydney, 3-6 Nov 2014 a shallow northen-sky survey grid of nested hexagons Dec >30° ! requires ~1300 pointings A phased approach(?):! 1) Supergalactic plane &! LOFAR selected areas! 2) SDSS area! 3) Galactic plane Periphery of Disks, Sydney, 3-6 Nov 2014 h medium-deep, wide area survey Four areas comprise footprint of medium-deep survey, largely driven by existing ancillary data: 90 sky areas of interest ° ° area! ‣ The HETDEX survey 60 75 2 million optical IFU redshifts, stacking! ° 45 group of galaxies! ‣ CVn 60° HETDEX 45° low-mass end of HIMF! ‣ Herschel-Atlas Northern Field! CVn group 30° SF, gas & galaxy evolution, Coma cluster! ‣ The Perseus-Pisces supercluster! environmental effects, magnetic fields ° nearby ! galaxies H-ATLAS full moon 15° 14h 12h 10h Spring fields overlap with MaNGA,! h are in SDSS h with coordinated h h h 20 resolved18 16 Pops, ISM, 14metallicities 12etc. 10 delivering info on Stellar Periphery of Disks, Sydney, 3-6 Nov 2014 Galactic Plane survey Characterize the multi-phase ISM ‣ HI and OH lines ! ‣ Radio Recombination Lines (HI & He) Special requirement: ! spectral zoom modes! on selected lines.! (R=0.2 km/s) Correlator mode! not available ab initio. Periphery of Disks, Sydney, 3-6 Nov 2014 Timeline Oct 2014 Critical Design Review! Dec 2014 go/no-go decision! draft survey definition! increase community involvement! Early 2015 start roll-out! setting up science working groups/teams! Late 2015 Apertif-6 available! technical commissioning, very early science! final survey strategy definition! Mid 2016 full Apertif-12 available! science verification! Early 2017 start of imaging surveys Periphery of Disks, Sydney, 3-6 Nov 2014
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