Dark Energy Survey Status John Peoples Presentation to the Fermilab PAC 6 March 2009

Fermilab PAC - 6 March 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 ~24 th 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 deg 2 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 deg 2 - SNe 1a survey: 5x3 deg 2 - Filters: g, r, i, z, Y, from DES and J, H & K from VHS Blanco 4-meter at CTIO Fermilab PAC - 6 March 2009

4 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 –DECam available for community use beyond the 525 nights Fermilab PAC - 6 March 2009

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 Fermilab PAC - 6 March 2009

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 Fermilab PAC - 6 March 2009

7 Lenses at SESO C5 grinding - Feb 2009 Polishing Tooling Fermilab PAC - 6 March 2009

8 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 Fermilab PAC - 6 March 2009

9 DECam Telescope Lab A The platform for testing DECam in all orientations It will test the installation of the filter changer, shutter and Imager into the cage from the service platform. It will test the connection of the cage with the telescope spiders Fermilab PAC - 6 March 2009

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. Fermilab PAC - 6 March 2009

11 A single simulated DECam pointing (= tile = hex) DECam Focal Plane 62 2kx4k Science CCDs (520 Mpix) 1 GB per single 3 deg 2 pointing Image Level Simulations Fermilab PAC - 6 March 2009

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 = WIYN 3.5m 02/27/09WIYN 3.5m 02/26/09 SDSS Public Data use by Fermilab DES Scientists

SSA_ SDSS J Lens z=1.018 z= Fermilab PAC - 6 March 2009

HST Cy16Sup GO PI Allam SDSS J

Preliminary ESSENCE SNLS 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 by Juan 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 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: ” 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/month Data Archive Server (SDSS Data served): 500 GBy/day 16Fermilab PAC - 6 March 2009

17 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 –Find and fix any problems at Fermilab before shipping to CTIO Ship DECam to CTIO and the barrel from UCL to CTIO: Nov Reassemble and test the DECam System: Dec Mar –The formal completion of DECam and acceptance for installation Install DECam and commission on the sky: Apr – Aug 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 The DES Team is ready and eager to pursue dark energy and dark matter, including Fermilab Scientists. Fermilab PAC - 6 March 2009

Additional Slides

19 DES Organization Fermilab PAC - 6 March 2009

20 Telescope Time and 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. Fermilab PAC - 6 March 2009

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) Fermilab PAC - 6 March 2009

22 Integrated Kapton Cable: CCD to Vacuum Interface Board CCD VIB Fermilab PAC - 6 March 2009

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. Fermilab PAC - 6 March 2009

24 DECam Clock Boards (CIEMAT: Madrid) Pre-production status: Qty 2 Clock_V2 boards have been delivered to FNAL; these boards have been used to readout CCDs Qty 4 Clock_V2 Transition modules have just been received 2 additional Clock_V2 boards will be produced and delivered to FNAL DECam Clock Transition Fermilab PAC - 6 March 2009

25 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 Transition Fermilab PAC - 6 March 2009

DES Forecasts: Power of Multiple Techniques Clusters:  8 =0.75, z max =1.5, WL mass calibration BAO: l max =300 WL: l max =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 not included 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. Fermilab PAC - 6 March 2009

SDSS-I + SDSS-II (footprint completed July 14, 2008) (Southern region not visible from Northern hemisphere) Northern Galactic Cap Imaging Complete SEGUE Spectroscopic Survey: of 200 sightlines 28

SDSS Science: Two nearly perpendicular stellar streams at kpc from the Sun are being explored to constrain the shape and extent of the Milky Way's Dark Matter halo. Galactic North polar plot Orphan Stream Sagittarius Stream 29 Fermilab PAC - 6 March 2009