dark energy survey status john peoples presentation to the fermilab pac 6 march 2009

Dark Energy Survey Status

John Peoples

Presentation to the Fermilab PAC

6 March 2009

Fermilab PAC - 6 March 20092

The DES Approach to Dark Energy

• DES will probe Dark Energy by measuring the expansion history of the Universe through– the dependence on redshift of the luminosity distance, angular

diameter distance, and volume element and – the growth rate of structure

• DES will use four complementary techniques, each of which will provide a good test of the nature of the dark energy. – Three will measure the spatial distribution of 300 M galaxies in

five bands to ~24th magnitude over the main DES Survey Area. – The fourth technique will exploit the nearly standard luminosities

of the type 1a SNe that will be found in the DES SN Survey.– The four will provide insight into systematic errors through their

complementarity.

3

The Dark Energy Survey

• 3 deg2 CCD camera (DECam)

• Data Management System (DES DM) and the Community Pipeline

• Improvements to the CTIO-Blanco infrastructure (CFIP)

• Two multiband surveys:

- Main Survey: 5000 deg2 - SNe 1a survey: 5x3 deg2 - Filters: g, r, i, z, Y, from DES and J, H & K from VHS

Blanco 4-meter at CTIO


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DECam-Fermilab Lead

• DECam:– Replaces the prime focus cage with a 2.2 deg.

dia. FOV, 520 Megapixel CCD camera

• Funding as of Mar 1, 2009:– DOE, NSF, STFC (UK), MEC (Spain), and the

collaborating Institutions have committed the required funding for DECam

• Status as of Feb 1, 2009:– R&D 95% complete (start FY05)– MIE 15% complete (start May 2008)

• DES and Community Use– DES allocation: 525 nights from Sep. to Feb.

during 2011-2016– DECam available for community use beyond

the 525 nights


5

CCD packages

• Fermilab builds and tests the CCD packages using CCDs procured from LBNL

• Package production line, including qualification testing, has started; 4 devices/wk capacity

• First science packages tested and qualified this week


6

Barrel Corrector and Imager

Lenses are being polished by SESO, cells are being fabricated by UCL in the UK and the barrel is being designed and built by Fermilab. A prototype lens cell has been fabricated and is being tested


7

Lenses at SESO

C5 grinding - Feb 2009

Polishing Tooling


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Front End Electronics and Imager integration

• The NOAO Monsoon CCD readout system was the starting point for the DECam readout.

• DES requires higher density boards for the prime focus location

• Preproduction versions DECam boards have been evaluated with the MultiCCD test Vessel

• Production of readout electronics will start this summer in Spain

• This was a major development challenge but it is done.

Imager Prototype/Multi-CCD Test Vessel


9

DECam Telescope Simulator @ Lab A

The platform for testing DECam in all orientations

It will test the installation of the filter changer, shutter andImager into the cage from the service platform. It will test the connection of the cage with the telescope spiders


10

Status of DESDM UIUC/NCSA Lead

• Status of Data Challenge-4 (DC-4):1 Oct 08 to 1 Feb 09– The full system DESDM system was operated for DC-4 , exclusive of

Oracle Real Application, to produce the DESDM Archive.– New Orchestration layer was incorporated and used to process

simulated data on the grid, which are produced by DECam. – Improved astronomy modules were incorporated, tested and used to

reduce DECam simulated data (detrending, single epoch photometry, co-addition, nightly astrometric calibration, global calibration, and model fitting photometry) and produced catalogs for the DES Archive.

– The WL lensing pipeline (an outside contribution) was incorporated.– The SNe pipeline (an outside contribution) was incorporated.– As Improved DES Archive was produced and archive portals were

incorporated to make the archive available to the science working groups.

• Testing of the DES archive products by science working groups and the DESDM team is underway and will continue to the start of DC-5.


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A single simulated DECam pointing (= tile = hex)

DECam Focal Plane

62 2kx4k Science CCDs(520 Mpix)

1 GB per single 3 deg2 pointing

Image Level Simulations


Two (of roughly 30) strong gravitational lenses found in SDSS data and followed up by Allam, Buckley-Geer, Kubo, Diehl, Flaugher and Tucker. Left: z= 2.09 arc with a 12.5” Einstein Radius

Right: 3 prominent arcs with possible counter images. Lower left arc has redshift

z = 0.97.

WIYN 3.5m 02/27/09 WIYN 3.5m 02/26/09

SDSS Public Data use by Fermilab DES Scientists

SSA_1004285SDSS J120923.7+264047

Lens z=1.018

z=0.558

13Fermilab PAC - 6 March 2009

HST Cy16Sup GO-11974PI AllamSDSS J120923.7+264047

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Preliminary

ESSENC

ESNLS

SDSS

Low-z Kessler et al to appear (2009)

Year one data only

SDSS-II completed observations on July 14, 2008

From High-Impact Astronomical Observatories byJuan P. Madrid (McMaster U.), Duccio Macchetto (STScI)

“We derive the ranking of the astronomical observatories with the highest impact in astronomy based on the citation analysis of papers published in 2006. We also present a description of the methodology we use to derive this ranking. The current ranking is lead by the Sloan Digital Sky Survey, followed by Swift and the Hubble Space Telescope. arXiv:0901.4552”

Fermilab hosted the management and data processing center for SDSS-I and SDSS-II. Fermilab continues to host and maintain that data archive, which is still very actively used:

Archive access summary for Oct-Dec 2008:Catalog Archive Server (SQL database): > 750,000 queries/monthData Archive Server (SDSS Data served): 500 GBy/day

16Fermilab PAC - 6 March 2009

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One slide takeaway message

• Final designs of all DECam components are in progress and many are already in fabrication. Design support presents a challenge.

• Assembly and testing of DECam as a system on the telescope simulator at Fermilab will begin in Jan and end in Oct 2010.– Find and fix any problems at Fermilab before shipping to CTIO

• Ship DECam to CTIO and the barrel from UCL to CTIO: Nov 2010. • Reassemble and test the DECam System: Dec 2010 - Mar 2011.

– The formal completion of DECam and acceptance for installation • Install DECam and commission on the sky: Apr – Aug 2011.• DECam is on schedule and budget; cash flow challenge in FY09 and

engineering and design support presents a continuing challenge • Start the Dark Energy Survey and community use of DECam in Sep.

2011• The DES Team is ready and eager to pursue dark energy and dark

matter , including Fermilab Scientists.


Additional Slides

19

DES Organization


20

Telescope Timeand Deliverables

• The DES Collaboration will receive up to 525 scheduled nights over a 5 year period on the Blanco 4-m telescope with DECam in order to carry out the Survey.

• In exchange for the telescope time DES will deliver the DECam System, which consists of the DECam instrument, the Community Pipeline and their interfaces to the Blanco and the E2E System, to NOAO for use by the NOAO Community and the Collaboration.


21

DECam overview

• CCD focal plane is housed in a vacuum vessel (the imager) which is supported by the barrel

• LN2 is pumped from the telescope floor to a heat exchanger in the imager: cools the CCDs to -100 C

• CCD readout electronic crates are mounted to the outside of the Imager and are actively cooled (UIUC).

• Filter changer (8 filter capacity) and shutter form one mechanical unit (UMichigan).

• Hexapod provides focus and lateral alignment capability for the corrector-imager system

• Barrel supports the lenses and imager

• DECam weighs about 4 tons (load limit is ~ 6 tons)


22

Integrated Kapton Cable: CCD to Vacuum Interface Board

CCDVIB


23

DECam Master Control Board (IFAE Barcelona)

• Master Control Board V2 has been designed by IFAE engineers in Barcelona.

• New board– updated obsolete parts from

NOAO design

– strips off unused logic

– allows for use of S-Link or Systran optical communication links

• 2 preproduction boards have been delivered to FNAL and are under test.


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DECam Clock Boards (CIEMAT: Madrid)

Pre-production status:

Qty 2 Clock_V2 boards havebeen delivered to FNAL;these boards have been usedto readout CCDs

Qty 4 Clock_V2 Transition modules have just been received

2 additional Clock_V2 boardswill be produced and delivered to FNAL DECam Clock DECam Clock

Transition


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DECam 12-Channel Acq Board (Fermilab)

•Pre-production board status:

•qty (7)12-Channel Board exist.

•All boards have passed testing and been calibrated.

•qty (9)Transition Cards are also completed and under test.

•qty(3) additional 12-Channel Boards will be produced.

DECam 12CH DECam 12CHTransition


DES Forecasts: Power of Multiple Techniques

Clusters: 8=0.75, zmax=1.5,WL mass calibration

BAO: lmax=300WL: lmax=1000

Statistical+photo-z systematic errors only

Spatial curvature, galaxy bias marginalized, Planck CMB prior

Factor 4.6 relative to Stage II

Assumptions:

geometric

geometric+growth

Stage II notincluded here

27

DESDM Project

• The DESDM Project deliverables are:– the DESDM System for the Collaboration and

– the Community Pipeline for the NOAO E2E system.

• These elements are being developed and commissioned primarily by personnel from NCSA and the Astronomy Department of UIUC, under the leadership of Professor Joseph Mohr, DESDM Project Leader, and Dr. Cristina Beldica, DESDM Project Manager.

• The DESDM system delivers science ready data products to the collaboration. It uses the grid to orchestrate the data processing and archive the DES data.

• The NOAO E2E system with the Community Pipeline provides processed DECam images that PIs cans use in their science software code.


SDSS-I + SDSS-II (footprint completed July 14, 2008)

(Southern region not visiblefrom Northernhemisphere)

Northern Galactic CapImagingComplete

SEGUESpectroscopicSurvey:of 200 sightlines

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SDSS Science:

Two nearlyperpendicularstellar streamsat 20-40 kpcfrom the Sunare being exploredto constrainthe shape andextent ofthe Milky Way'sDark Matterhalo.

Galactic Northpolar plot

Orphan Stream

Sagittarius Stream29


dark energy survey status john peoples presentation to the fermilab pac 6 march 2009

Documents

ctiofermilab pac

weekfermilab pac

nightsfermilab pac

fermilab pac6

decamfermilab leaddecam

telescope spidersfermilab

polishing toolingfermilab

decam readout