the vista hemisphere survey(vhs)

April, 4, 2008 NAM2008, Belfast 1

The VISTA Hemisphere Survey(VHS)

Richard McMahonInstitute of Astronomy

University of Cambridge


The VHS Collaboration (Institute epoch mid-2007)PI: Richard McMahon

Collaboration Management Board: Castander, Emerson, Lawrence, McMahon, Rebolo, Rix

UK (members from 13 of the 18 VISTA Consortium Universities + 5 non VC):Birmingham(v): SmithBristol: Bremer, PhillipsCambridge(v): Belokurov, Gilmore, Gonzalez, Hodgkin, Irwin, McMahon, Riello, Venemans, Walton,

ZuckerCardiff(v): DaviesDurham(v): Alexander, Edge, Shanks Edinburgh(v): Ferguson, Hambly, Lawrence, Mann, PeacockExeter: NaylorHerts(v): Cioni, Jarvis, Jones, Lucas, PinfieldLeicester(v): Jameson, O,Brien, Tanvir, WatsonLiverpool JM(v): JamesOpen: SerjeantOxford(v): Dalton, Rawlings, WolfPortsmouth: Crittenden, Edmundson, Nichol, PercivalQMUL(v): Emerson, SutherlandSt Andrews(v): DriverSussex(v): Loveday, Liddle, Oliver, Romer, UCL(v): Abdalla, Bridle, Doel, Lahav, Page, WellerIC: Rowan-Robinson, Warren


The VHS Collaboration (continued)6 non-UK ESO nations + Chile; Chile(1 Institute):

MazaFrance(5 Institutes):

Paris(IAP): Omont, PetitjeanParis(IAS): Lagache, Puget, Grenoble: Bouvier, MourauxStrasbourg; Ibata,MartinToulouse: Caux, Webb,

Germany(3 Institutes):AIP: Scholtz, Swope, ZinneckerBonn: KroupaMPIA: Balier-Jones, Bell, Goldman, Rix, Somerville, Walter

Italy(1 Institute): Randich(Arcetri), Palla(Arcetri), Testi(Arcetri)

Netherlands(1 Institute): Rottgering(Leiden)

Portugal(1 Institute): Garcia(Porto), Viana(CAUP),

Spain:Barcelona: Castander, Fernandez, Fosbala, Gaztanaga, Miralda-Escude, Mique, ….Granada: Beniiez, …IAC: Alfonso, Balcells, Cairos, Espinosa, Garzon, Lodieu, Martin, Perez-Fournon, Rebolo, …Madrid: Barrado, Garcia-Bellido,Sanchez, …Santander; Barcons, Carrera,


Visible and Infrared Survey Telescope for Astronomy

• 4.1m primary mirror, wide field survey telescope ; 1.5deg diameter field of view; designed for both optical and near infra-red.

• Funded in 1999 from 600m UKP Government/Wellcome Joint Infrastructure Fund(JIF).

• UK project (consortium of 18 Universities)– Principal Investigator: Jim Emerson (QMUL, London)– Project Scientist: Will Sutherland (Cambridge QMUL, London)

• Located at European Southern Observatory (ESO) , Paranal near the VLT site.

• Now Infra Red camera only. [16 detectors 2kx2k up from 9 in original proposal]

• Will become ESO facility on completion of construction and ‘hand over’ in Oct, 2008 (part of UK’s ESO late joining fee)


ESO VISTA Public Surveys• >75% of VISTA time is for large scale Public Surveys• March, 2006 Initial proposal

– 16 proposals– 6 up-selected for next phase– VHS, VIKING, VIDEO, VMC, VVV, Ultra-VISTA

• Nov, 2006; VHS was highest scientifically ranked by ESO OPC

• Nov, 2007 VHS Survey Management(SMP) plan accepted by ESO.– Survey management plan requested 3402 clear hours of observing time

which assumes 65% observing efficiency; ~380nights of service mode observing over a 5 year period.


VHS Science Goals• The nearest and lowest mass stars• Galactic structure; formation of the Milky Way • Evolution of Large scale structure in the Universe; the

nature and evolution of Dark Energy• The physics and baryonic content of the Epoch of

Reionization; the discovery the first z>7 quasar(s).

100 times volume of Universe compared with 2MASS10 times the volume of the Universe compared UKIDSS

• Targets for the VLT, ALMA, ELT, JWST• Support for ESA Survey Missions:

– XMM-Newton, Herschel, Planck, GAIA


Legacy goals of VHS survey• 21st century near IR covering 20,000deg2 of Southern

celestial hemisphere when VHS coverage combined with the other 3 large area VISTA public surveys.– VIKING, VMC, VVV

• Large samples of objects for high statistical significance;

• Large area/volume to find Rare objects;– Nearest, Farthest, Mostest, Bestest

• Large area for Large Scale Structure– Extragalactic; Dark matter and Dark Energy– Galactic Structure; Formation of our our Galaxy

€

N >>100 × N


VHS Components• VHS Galactic Plane (VHS-GP)

– 5< |b| <30– 8200deg2

– J(60sec); K(60sec)

• VHS-ATLAS (VST-ATLAS PI: Shanks)– 5000deg2

– Y(60sec), J(60sec), H(60sec), K(60sec)

• VHS-Dark Energy Survey(VHS-DES)– 4500deg2 ( excludes 500deg2 from VIKING footprint)– J (120sec), H(120sec), K(120sec) – 2nd pass planned in future


VHS Sky coverage footprint


VHS and VST-Atlas footprint


VHS limiting magnitudes [AB system; 5]

VHS Component deg2 Y J H K

VHS-ATLAS 5000 20.9 20.9 20.3 19.8

VHS-DES 500021.922.3

21.2 20.8 20.2

VHS-GP 8200 20.9 19.8

UKIDSS-LAS2000

(4000)20.8 20.5 20.2 20.1


The missing V for Visible in VISTA• As part of the ESO negotiations the IR field of view of VISTA

was increased from 9 IR detectors to 16 detectors.

• The optical camera was deemed of secondary importance since IR capability was the highest priority and increased the unique value of VISTA to the ESO community which includes the UK.

• Thus the IR ‘entendue’ of VISTA increased by a factor of 3 from larger detector real estate AND 100% of time would be IR.


The Dark Energy Survey(US, UK, Spain, Brasil collaboration)

• Telescope; upgraded CTIO 3.9m• 525 nights over 5 years• Starting Dec 2008• Multiple pass survey so coverage of

5000deg2 in first year.• Field of view

• 2.3deg diameter; 3.0deg2

• Very red sensitive CCDs • QE; 90% at 900nm; 50% at 1m

• g, r, i, z, Y wavebands

DECam Focal Plane

62 2kx4k Image CCDs: 520 MPix8 2kx2k focus, alignment CCDs

4 2kx2k guide CCDs0.27” per pixel


Pre-DES optical data• SDSS-3(BOSS): 2000deg2 to SDSS depth; 1000deg2 in

VHS footprint– From SDSS-3 website: “During Fall 2008, BOSS will use the SDSS camera to carry out an additional 2,000 square degrees of imaging at high Galactic latitude in the southern Galactic cap, filling the gaps between the SDSS southern stripes.”

– Date Release; DR9; July 2010• VLT Survey Telescope(VST) (survey to start in 2009)

– VST-ATLAS survey (PI: Tom Shanks, Durham)• Skymapper (survey to start in 2009)• PAN-STARRS for part of VHS footprint (data

proprietary until?)


VHS Summary• Highest scientifically ranked ESO VISTA Public Survey

– 100 times volume of Universe compared with 2MASS– 10 times the volume of the Universe compared UKIDSS

• Survey management plan accepted by ESO in Nov; 2007

• 5 year program starting in late 2008 or early 2009.– Requested time is 3000-3400hrs of clear time assuming 65% observing

efficiency; equivalent to 330-380 clear nights

• Data will be processed by VISTA Data Flow System(VDFS) operated by Cambridge and Edinburgh groups.


VISTA primary mirror mates with VISTA telescope; 31 Mar 2008

the vista hemisphere survey(vhs)

Documents

eso facility

eso opcnov

uks eso

walteritaly1 institute

vista time

vhs survey managementsmp

survey management plan

infrared survey telescope