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David James (CTIO) for the Dark Energy Survey Pan-STARRS1: Science Results STScI , Baltimore - 24 June 2014

The Dark Energy Survey:. Dark Energy Camera – DES: YR1 of the Dark Energy Survey. David James (CTIO) for the Dark Energy Survey Pan-STARRS1: Science Results STScI , Baltimore - 24 June 2014. The Dark Energy Survey:. Survey project to probe signatures of

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David James (CTIO) for the Dark Energy Survey Pan-STARRS1: Science Results STScI , Baltimore - 24 June 2014

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  1. The Dark Energy Survey: Dark Energy Camera – DES: YR1 of the Dark Energy Survey David James (CTIO) for the Dark Energy Survey Pan-STARRS1: Science Results STScI, Baltimore - 24 June 2014

  2. The Dark Energy Survey: • Survey project to probe signatures of • Dark Energy using four complementary • techniques: • Cluster Counts • Weak Lensing • Large-scale Structure • Supernovae • Two multiband surveys: • 5000 deg2: 10σgriz(Y) to 24th (21.6th) mag • 30 deg2: repeated SNe fields • Build new 3 deg2FoV camera • and data management system: • Survey 2013-2018 (525 nights) • Facility instrument for Blanco Blanco 4-metre Telescope at CTIO http://lsst.org Pan-STARRS1: Science Results Dark Energy Survey David James

  3. The DES Collaboration Fermilab University of Illinois at Urbana-Champaign/NCSA University of Chicago Lawrence Berkeley National Lab NOAO/CTIO DES Spain Consortium DES United Kingdom Consortium University of Michigan Ohio State University University of Pennsylvania DES Brazil Consortium Argonne National Laboratory SLAC-Stanford-Santa Cruz Consortium Universitats-Sternwarte Munchen Texas A&M University plus Associate members at: Brookhaven National Lab, U. North Dakota, Paris, Taiwan Several hundred members plus students & postdocs Funding: DOE, NSF; UK: STFC, SRIF; Spain Ministry of Science, Brazil: FINEP, Ministry of Science, FAPERJ; Germany: Excellence Cluster; collaborating institutions Pan-STARRS1: Science Results Dark Energy Survey David James

  4. DarkEnergyCamera: A new prime focus instrument CCD Readout Filters + Shutter Focal plane (detector, 62+ CCDs) Hexapod Corrector Lenses Pan-STARRS1: Science Results Dark Energy Survey David James

  5. Brave New World: DECam Pan-STARRS1: Science Results Dark Energy Survey David James

  6. Controlling DECam: SISPI • Data Flow: • Image acquisition (Panview, 6 Monsoon crates) • Image Builders (multiple instances) • FITS formatting • Image Health • Telemetry • Compression • Submit to NCSA (DTS) • Observation Control: • OCS (pipeline architecture) • OBSTAC • Instrument Control: • Internal (shutter, hexapod, filters) • External (cooling, temperatures, ICC) • Guider & Focus: • Interfaces to TCS & Cloud Camera: SISPI is the DECamdata acquisition and control system: Pan-STARRS1: Science Results Dark Energy Survey David James

  7. The Dark Energy Camera: Detector 2k x 2k Focus & Alignment 2k x 2k Guide 2k x 2k Focus & Alignment 2k x 2k Guide Pan-STARRS1: Science Results Dark Energy Survey David James

  8. 2 tilings 3 tilings (original) DES Observing Strategy: • Sept-Feb observing seasons • 80-100 sec exposures • 2 filters per pointing (typically) • grin dark time • izyin bright/grey time • Photometric calibration: overlap tilings, standard stars, spectrophotometric calibration system, preCAM • 2 survey tilings/filter/year • Interleave 10 SNe fields in griz if non-photometric or bad seeing or time gap (aim for ~5 day cadence) Pan-STARRS1: Science Results Dark Energy Survey David James

  9. (present) DES Observing Strategy: Year 1 regions SDSS Stripe 82 • Year 1: • Moved footprint eastward to reduce secZ, improve image quality • Cover 2000 sq. deg. (4 tilings per filter) rather than full 5000 sq. deg. (2 tilings) to improve photometric calibration • Allow g, Y observations with seeing>1.1” (not used for Weak Lensing). • Year 2: • Complementary 3000 sq. deg. • Optimize: many more half-nights than YR1 SPT By end of YR2, expect will have done 90% of the exposures needed to complete 4 tilings of the 5000 sq. deg. footprint. Pan-STARRS1: Science Results Dark Energy Survey David James

  10. Dark Energy Survey: Year 1 • DES started taking YR1 data on Aug. 31st 2013 • In January, we switched to 1st half nights • Finished YR1 in mid-February 2014 Pan-STARRS1: Science Results Dark Energy Survey David James

  11. DES: Observing Sequences Pan-STARRS1: Science Results Dark Energy Survey David James

  12. Year 1 (vs. SVA1): Exposure Breakdown Pan-STARRS1: Science Results Dark Energy Survey David James

  13. First DES YR1 Image • 31st Aug. 2013 23:55 Local Chilean Time • Image DECam_00229250 was transferred to NCSA in Urbana where; • DES “Data Management” processed it and made a catalog of the stars and roughly 100,000 galaxies that can be identified in it. First DES YR1 image is #229250 Pan-STARRS1: Science Results Dark Energy Survey David James

  14. DES Operations EfficiencyMeasurements • Only 2 problems lasted as long as 4 consecutive hours: In Oct. we lost a night from a TCS software bug. In Nov. we lost 1½ nights due to problems w/ electronics: noise and missing backplanes, then CCD S30 failed. • The other problems are computer interfaces issues, … mostly, shutter resets • Shutter was open 63% of “Observing Time” during YR1. Dome control improvements gave us ~4% better efficiency starting in late December 2013. Pan-STARRS1: Science Results Dark Energy Survey David James

  15. DES WFSurvey • Goal was to observe 4 “tiles” of ~672 images per tile in each of 5 filters • 13435 images total • Plots here show what we obtained: • Gaps in Stripe 82 (North) • Gaps in Sept. to Nov. survey area (West) • Images in YR2 fields because nothing “available” from YR1 particularly in late Jan. to Feb. ~3k images (17%) of YR2 Pan-STARRS1: Science Results Dark Energy Survey David James

  16. DES SN Survey: YR1 Observations • 10 SN fields. 2 of those are “deep fields” • Our plot shows day-by-day SNe cadence • 2565/2699 SNe exposures “good” (95%) • After 7-days, even when the weather is good, SNe team gets their data on “deadman” condition of OBSTAC. Pan-STARRS1: Science Results Dark Energy Survey David James

  17. DES Observing: YR2 Pan-STARRS1: Science Results Dark Energy Survey David James

  18. First DES (SV) Science Paper: 2014arXiv1405.4285M Pan-STARRS1: Science Results Dark Energy Survey David James

  19. Community Use of DECam: • DECam-NEOO: • Lori Allen (NOAO – PI) • 3-yr survey time awarded • 1st 10-night block executed April 2014 • Early results are very encouraging • Light-echoes of SNe remnants: • Armin Rest (STSci– PI) • many nights per semester • étendue of DECam critical • latest results are now available: Prieto et al. 2014, ApJL, 787, L8 Pan-STARRS1: Science Results Dark Energy Survey David James

  20. DECam Current Status • Sensor array is OK except • Two CCDs are no longer functioning correctly: • N30 11/07/2012 • S30 11/28/2013 • 8 CCDs ~12e- RO noise (7e- is typical), spec is 15 e-. Problem comes and goes since late Nov. • S7 (½ CCD) non-linearity unstable at very low light levels (<1000e-). • Two focus chips have 1 “weak” amplifier. S30 S7 N30 Pan-STARRS1: Science Results Dark Energy Survey David James

  21. The DES Collaboration Thank you ! Pan-STARRS1: Science Results Dark Energy Survey David James

  22. The DES Collaboration Pan-STARRS1: Science Results Dark Energy Survey David James

  23. The DES Collaboration Pan-STARRS1: Science Results Dark Energy Survey David James

  24. NOAO NCSA For details, ask Brian Yanny, DES Data Coordinator, or Robert Gruendl, UIUC

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