1 / 25

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

tehya
Download Presentation

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

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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

More Related